U.S. patent application number 11/567660 was filed with the patent office on 2007-05-17 for temperature conditioning radiant wall system for buildings.
Invention is credited to Ross SINCLAIRE.
Application Number | 20070108307 11/567660 |
Document ID | / |
Family ID | 38057280 |
Filed Date | 2007-05-17 |
United States Patent
Application |
20070108307 |
Kind Code |
A1 |
SINCLAIRE; Ross |
May 17, 2007 |
TEMPERATURE CONDITIONING RADIANT WALL SYSTEM FOR BUILDINGS
Abstract
A temperature conditioning system for a plurality of suites of a
high rise building is provided utilizing at least domestic hot
water circulated through tubing fit to a radiant wall in a suite
for heating the suite. A hot water heating system in communication
with a supply riser and return riser provides hot water at variable
pressure to each of the multiple serviced floors. Hot water is
cirulated through distribution mains to radiant walls in the suites
at full riser pressure, while pressure reducing valves off of the
distribution mains lower the hot water pressure to domestic service
pressures at plumbing fixtures. Similarly, domestic cold water can
be chilled and circulated through the radiant walls for cooling.
Three-way valves at the radiant wall can alternately circulate hot
water or cold water under thermostatic control.
Inventors: |
SINCLAIRE; Ross; (Calgary,
AB) |
Correspondence
Address: |
SEAN W. GOODWIN
222 PARKSIDE PLACE
602-12 AVENUE S.W.
CALGARY
AB
T2R 1J3
CA
|
Family ID: |
38057280 |
Appl. No.: |
11/567660 |
Filed: |
December 6, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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10851349 |
May 21, 2004 |
|
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11567660 |
Dec 6, 2006 |
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Current U.S.
Class: |
237/69 |
Current CPC
Class: |
F24D 3/12 20130101; F24D
3/08 20130101; Y02B 30/00 20130101 |
Class at
Publication: |
237/069 |
International
Class: |
F24D 5/10 20060101
F24D005/10 |
Claims
1. A system for temperature control in one or more suites of a high
rise building having multiple serviced floors, each serviced floor
having the one or more suites serviced with at least domestic hot
water, the one or more suites having domestic use fixture therein,
the system comprising: a hot water heating system for heating the
domestic hot water; a hot water supply riser extending to each of
the multiple serviced floors, fluidly connected to the hot water
heating system, and in which a pressure of the domestic hot water
therein varies with elevation; a hot water return riser extending
to each of the multiple serviced floors and fluidly connected to
the hot water heating system; a hot water distribution main
extending from the hot water supply riser at each serviced floor
for servicing the one or more suites for the serviced floor; a hot
water return main, extending from the hot water return riser at
each serviced floor, for returning the domestic hot water from the
hot water distribution main for the serviced floor to the hot water
heating system and establishing circulation therethrough; and at
each of the one or more suites, further comprising at least one
radiant wall fit with thermal tubing for circulation of hot water
between the hot water distribution main and the hot water return
main; and at each serviced floor at which the pressure of the
domestic hot water in the hot water distribution main is above a
hot water pressure threshold, further comprising one or more hot
water pressure reducing valves located between the hot water
distribution main and the domestic use fixtures of each of the one
or more suites for providing domestic hot water to the domestic use
fixtures at a domestic service pressure.
2. The system of claim 1 wherein the hot water pressure threshold
is above the domestic service pressure.
3. The system of claim 1 wherein each hot water distribution main
further comprises a flow control valve between the hot water
distribution main, at about a last suite of the one or more suites
in series, and the hot water return main.
4. The system of claim 1 further comprising a thermostatic control
for controlling the circulation of domestic hot water through the
radiant tubing.
5. The system of claim 1 further comprising at least one auxiliary
heating loop positioned at a location experiencing additional heat
loss than can be accommodated by the radiant wall alone, the
auxiliary heating loop being fit with the thermal tubing for
circulation of hot water between the hot water distribution main
and the hot water return main.
6. The system of claim 1 wherein the one or more suites comprise
interior suite and end suites, the end suites experiencing higher
heat loss than can be accommodated by the radiant wall alone, and
wherein the auxiliary heating loop is embedded in the floor of the
suite adjacent the higher heat loss.
7. The system of claim 1 wherein the radiant wall is a partitioning
wall dividing two rooms of the suite for heating both rooms.
8. The system of claim 1 wherein the radiant wall is a party wall
dividing a heated room of a first suite and a second suite, further
comprising insulation between the radiant wall and the second suite
for directing heat to the first suite.
9. The system of claim 1 wherein the heating system is a
boiler.
10. The system of claim 1 wherein the heating system is a heat
pump.
11. The system of claim 1 wherein each serviced floor is serviced
with domestic cold water, further comprising: a cold water supply
riser extending to each of the multiple serviced floors and in
which the pressure of the domestic cold water therein varies with
elevation; a cold water distribution main extending from the cold
water supply riser at each serviced floor for servicing the one or
more suites for the serviced floor; and at each serviced floor at
which the pressure of the domestic cold water in the cold water
riser is above a cold water pressure threshold, further comprising
at least one cold hot water pressure reducing valve located between
the hot water distribution main and the domestic use fixtures of
each of the one or more suites for providing domestic cold water to
the domestic use fixtures at a domestic service pressure for
domestic use fixtures.
12. The system of claim 11 further comprising: a cooling system for
cooling the domestic cold water and wherein the cold water riser is
fluidly connected to the cooling system; a cold water return riser
extending to each of the multiple serviced floors and fluidly
connected to the cooling system; a cold water distribution main
extending from the cold water supply riser at each serviced floor
for servicing the one or more suites for the serviced floor; a cold
water return main extending from the cold water return riser at
each serviced floor for returning the domestic cold water from the
cold water distribution main for the serviced floor to the cooling
system and establishing circulation therethrough.
13. The system of claim 11 wherein at each of the radiant walls of
the one or more suites, further comprising a first three way valve
for alternately connecting an inlet end of the thermal tubing to
the hot water distribution main for heating the radiant wall and
the cold water distribution main for cooling the radiant wall.
14. The system of claim 13 wherein, at each of the radiant walls of
the one or more suites, further comprising a second three way valve
for alternately connecting a discharge end of the thermal tubing to
the hot water return main while heating and the cold water return
main while cooling.
15. The system of claim 14 further comprising a thermostatic
control for controlling the first and second three way valves.
16. The system of claim 11 wherein the cooling system is a
chiller.
17. The system of claim 11 wherein the cooling system is a heat
pump.
18. A method of controlling the temperature of one or more suites
of a high rise building having multiple serviced floors, each
serviced floor having the one or more suites serviced with at least
domestic hot water, the one or more suites having domestic use
fixtures therein, the system comprising: supplying domestic hot
water to each serviced floor at full water pressure which varies
with elevation, the water pressure at an uppermost floor being at
or above domestic service pressures; and at each serviced floor,
controlling the circulation of the domestic hot water through one
or more radiant walls in the one or more suites; and at each
serviced floor having full water pressures above a domestic service
pressure suitable for the domestic use fixtures, reducing the water
pressure of the domestic hot water before the domestic use fixtures
to the domestic service pressure.
19. The method of claim 18 wherein the supplying of domestic hot
water to each serviced floor comprises: supplying hot water to each
serviced floor in a hot water riser extending to each serviced
floor, further comprising at each serviced floor: distributing the
domestic hot water from the hot water riser through a hot water
distribution main for circulating the domestic hot water through
one or more radiant walls; and reducing the water pressure of the
domestic hot water between the hot water distribution main and the
domestic use fixtures where full water pressure is above the
domestic service pressure.
20. The method of claim 18 wherein heating and cooling of the one
or more suites is desired, further comprising: supplying domestic
cold water to each serviced floor at full water pressure which
varies with elevation, the water pressure at an uppermost floor
being at or above domestic service pressures; and at each serviced
floor, controlling circulation of the domestic cold water through
the one or more radiant walls in the one or more suites; and at
each serviced floor having full water pressures above a domestic
service pressure suitable for the domestic use fixtures, reducing
the water pressure of the domestic cold water before the domestic
use fixtures to the domestic service pressure.
21. The method of claim 18 wherein only heating of the one or more
suites is desired, further comprising: supplying domestic cold
water to each serviced floor at full water pressure which varies
with elevation, the water pressure at an uppermost floor being at
or above domestic service pressures; and reducing the water
pressure of the domestic cold water to the domestic service
pressure before distribution of the domestic cold water at each
serviced floor having full water pressures above the domestic
service pressure.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of co-pending US
application 10/851,349 entitled "MULTI-STORY WATER DISTRIBUTION
SYSTEM" and which was filed May 21, 2004, the entirety of which is
incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to systems for the heating and
cooling of buildings, reduction in capital expense, and the
distribution of water for minimizing the number of piping risers
and avoiding over-pressure supplies through the strategic placement
of pressure reducing valves.
BACKGROUND OF THE INVENTION
[0003] Heating and cooling systems for multi-story buildings
typically use specifically supplied and circulated hot and cold
water for delivery to heat exchangers. Traditionally, room-by-room
heating, and air conditioning systems in large buildings have been,
what are known in the art, as four-pipe fan-coil systems; two pipes
for chilled water flow, and two pipes for heated water flow.
Individual fan-coil units placed at various locations throughout
the building provide for zonal temperature control. Heating or
cooling is provided by having the fan circulate air over a coil
that is accessing either the hot or the chilled-water piping
system, respectively. Water distribution systems for multi-story
buildings also typically comprise various arrangements of water
supply and returns.
[0004] Conventional 8 floor zones extend risers up through all
suites with the associated water noise for the lower suites and the
large number of risers. Each riser is associated with fire blocking
and challenges at bulkheads and cross-over floors.
[0005] To date, choices for heating and cooling commercial or
multi-suite buildings have been limited and equipment such as fan
coils are an expensive, but known, solution.
[0006] Multi-story buildings further introduce challenges including
problems related to hydrostatic pressure variation from floor to
floor. In a 24 storey building the pressure at the lowest floor may
be about 130 psig so as to maintain 40 psig at the highest of the
upper floors or roof where the hydraulic head is at its minimum. To
supply a 72 storey building from a single water supply riser would
result in pressures at the lowest floor at about 250 psi. However,
it is unacceptable to apply 250 psi or even 130 psig water for
domestic use. Higher pressure in a domestic hot water system will
ensure return flow to the hot water boilers but such pressures are
too high for domestic purposes.
[0007] There is a need for a reduction in redundant piping,
elimination of noise in suites, lower capital cost and more
efficient systems in the heating, cooling and distribution of
domestic water in high rise buildings. Applicant addresses these
shortcomings and incorporates further improvements to heating and
cooling systems, some of which can be incorporated with domestic
water distribution.
SUMMARY OF THE INVENTION
[0008] Applicant has provided a system which significantly reduces
the piping needed to supply domestic hot and cold water to one or
more units, residences or suites in high rise buildings, solves
issues associated with the supply of water at pressures above
desired domestic use pressures, and incorporates novel heating
concepts for multi-residence buildings. The number of risers
throughout can be reduced in number by more than an order of
magnitude. Noise issues associated with flow in risers extending
through each suite is eliminated.
[0009] Applicant has recognizes that use of domestic water system
for heating and cooling using partitioning walls as radiant walls,
enables heating and cooling of adjacent rooms and better utilizes
existing domestic water systems for minimizing capital expenditures
such as through the reduction or elimination of fan-coil or
hydronic radiant panel devices.
[0010] The partitioning walls condition room temperatures by acting
as a cold or hot radiant wall either using hot domestic water for
heating, or using chilled domestic water for cooling, or
alternating therebetween using thermostatic valves for circulating
either the heated domestic water or chilled domestic water.
[0011] Applicant further recognized that several aspects of
pressure control at lower floors provides significant advantages.
Use of full pressure, variable over elevation, domestic cold and
hot water systems and pressure reducing valves as required for
domestic service only, eliminates floor to floor risers and
remarkably reduces the numbers of piping runs. Pressure and flow
control is maintained despite the number of floors in the building.
No longer do domestic water pressure and plumbing fixture
requirements limit the use of common risers at full pump pressure
at full hydrostatic head. Further, the system has several solutions
for ensuring hot water availability and avoiding stagnation which
can occur in some domestic lines, contrary to public safety and
contrary to plumbing regulations in some jurisdictions.
[0012] In one embodiment, the system has a domestic hot water
supply riser and a hot water return riser. At each serviced floor,
a domestic hot water distribution main extends from the hot water
supply riser to each of one or more suites and returns to the hot
water return riser. On each floor, typically lower floors, at which
a riser pressure is higher than preferred service pressure for
domestic plumbing fixtures, a pressure reducing valve is situated
at least between the distribution main and domestic use fixtures in
the suites for reducing the pressure of the cold and the hot water
as required. Coupling of the heating systems directly off of the
supply riser at full water pressure and to the hot water
distribution main provides an effective piping system for
circulation of hot water through heating systems and allows for
return of hot water circulation to the heating system without a
need for further pumping. Further, implementation of a
substantially constant circulation of hot water through the hot
water distribution main ensures hot water is available on demand.
Additionally, when heating is not required, regular and periodic
circulation through the hot water distribution main avoids
stagnation of the domestic hot water supply.
[0013] As a result, applicant has determined that up to 70% can be
saved on the fluid piping in a building and 20% on the cost of the
entire mechanical system. Supply risers no longer run through
suites, eliminating noise. Bulkheads and cross-over floors are no
longer a concern for domestic water distribution. Water circulation
is simplified without a need for auxiliary pumps to return spent
water to heating and cooling systems. With reduced numbers of
risers comes less wasted floor area for accommodating piping. Use
of domestic hot water for heating, and as desired domestic cold
water for cooling reduced capital cost by reducing or eliminating
fan coils and other equipment.
[0014] In one broad aspect, a system for temperature conditioning
multiple serviced floors of a high rise building is provided, each
floor having one or more suites having interior and exterior walls
and having plumbing fixtures being serviced with at least domestic
hot water. Such a system comprises: providing at least a domestic
hot water distribution main at a supply pressure at each serviced
floor for servicing the suites. The domestic hot water distribution
main provides domestic hot water to one or more suites on the
floor. The domestic hot water is thermostatically controlled
through radiant tubing installed in one or more radiant walls in a
suite, of one or more suites, for heating the suite. For each floor
at which the supply pressure of the domestic hot water is above a
first pressure threshold, typically a suitable domestic service
pressure, the water pressure of the hot water to the domestic use
fixtures is reduced to about the first threshold pressure using one
or more pressure reducing valves situated between the distribution
main and the domestic use fixtures of each suite.
[0015] Preferably, the system further comprises a domestic cold
water distribution main for each serviced floor at a supply
pressure. In embodiments where cooling is not required, such as in
moderate climates, and for each floor at which the supply pressure
of the domestic cold water supply at each floor is above a second
pressure threshold, typically the suitable domestic service
pressure, the water pressure of the cold water is simply reduced at
the before the distribution main. Where cooling using domestic cold
water is employed as well for the radiant walls, one can maintain
the domestic cold water distribution main at full pressure for
radiant wall circulation and, as applied to the domestic hot water,
reduce the water pressure of the cold water to the domestic use
fixtures to the second threshold pressure using one or more
pressure reducing valves situate between the full pressure cold
water distribution main and the domestic use fixtures of each
suite.
[0016] Preferably, a heating system or heater provides heated hot
water to each domestic hot water distribution main, and a hot water
return riser returns hot water from the distribution mains to the
heater. Similarly, a cold water riser provides chilled cold water
from a cooling system or chiller to each floor's distribution main,
and a cold water return riser returns cold water from each
distribution main to the chiller.
[0017] For heating and cooling using radiant walls, a pair of
three-way valves are employed, a first three-way valve controls
whether chilled or heated domestic water is circulated into the
tubing in the radiant wall, and a second three-way valve controls
whether the thermally spent water returning from the radiant wall
is returned to the cold water return riser or the hot water return
riser respectively.
[0018] Preferably the domestic hot water main is fit with a flow
control valve to flow back to the return riser so as to provide a
controlled, yet substantially constant flow of hot water for
ensuring a substantially on-demand hot water response at the
domestic use fixtures. Preferably the flow control valve is
positioned between the distribution main after the last serviced
suite, and a return main to the return riser. The radiant walls and
other heating loops can be provided with thermostatically
controlled valves having periodic dump features to avoid
stagnation.
[0019] Typically radiant wall are provided on interior walls of a
suite for bi-directional heating. More preferably, suites adjacent
an exterior wall, and similarly adjacent utility or common areas
such as stairwells, can be provided with additional radiant tubing
installed in the floor such as adjacent the exterior wall. As
necessary, walls between adjacent suites can be fit with radiant
walls, but are arranged for unidirectional heating to the suite
having the thermostatic control.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is a schematic plan view of an arrangement of a hot
wall heating system arranged in an intervening partition wall
dividing two rooms of a suite;
[0021] FIG. 2 is a schematic elevation view of radiant tubing
arranged in a radiant wall and operating at full hot water supply
pressures;
[0022] FIG. 3A is a schematic elevation of a high rise building
implementing some of the heating and cooling features of the
present invention;
[0023] FIG. 3B is a schematic elevation of a high rise building
implementing only heating features of the present invention;
[0024] FIG. 3C is a schematic of adjacent suites of a lower floor
according to FIG. 3A and illustrating the hot and cold water
distribution mains and pressure reducing valves to fixtures;
[0025] FIG. 4 is a schematic plan view of an arrangement of a hot
wall heating system arranged on the facing wall of a single suite
to avoid heat transfer or loss through the facing wall, such as to
an adjacent suite or non-suite;
[0026] FIG. 5 is a schematic plan view of an arrangement of a hot
wall heating system arranged in an intervening partition wall
dividing two suites where one of the two suites is adjacent an
exterior wall and the radiant tubing is expanded to include
auxiliary floor heating; and
[0027] FIGS. 6A and 6B illustrate the domestic hot water and
domestic cold water piping to typical plumbing fixtures in a
suite.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0028] Generally, as shown in FIG. 1, adjacent rooms 10a,10b within
a suite 11 are separated by a walls 12, such as an interior
partitioning wall 13. During seasons where the rooms 10a,10b
require heating, one or more of the walls 12 can be operated as hot
radiant walls 20. In the case of an interior partitioning wall 13
operated as a radiant wall 20, heat radiates bi-directionally into
the suite 11 in both directions to adjacent rooms 10a,10b. An
interior partitioning wall 13 within a suite 11 is a convenient
embodiment for a bi-directional radiant wall 20 wherein a suite
occupant can control the radiant output solely for their suite 11.
One is less inclined to operate a party wall 14, located between
adjacent suites 11a,11b, as a bidirectional radiant wall 20 because
thermostatic control by an occupant in one suite 11 a can also
affect the comfort of an occupant of the adjacent suite 11b.
Options include either avoiding the implementation of radiant walls
20 in a party wall between suites 11a,11b or instead to configure
such radiant walls 20 for unidirectional radiant thermal
control.
[0029] While referred to as a "radiant" wall, which suggests
radiant heat transfer, other aspects of the principles of heat
transfer are also inherent and contemplated, such as conduction to
the wall surface and convection therefrom. Further, radiant walls
20 can provide thermal control including either heating and
cooling. While examples are provided in terms of a hot radiant wall
20, heated using domestic hot water DHW, temperature conditioning
or thermal control using a radiant wall 20 can equally include
cooling using a circulation of domestic cold water DCW. Temperature
adjusted water, which is circulated through radiant walls 20 for
temperature control, is generally termed herein as thermal water
and more specifically as domestic cold water DCW or domestic hot
water DHW.
[0030] With reference also to FIG. 2, the radiant wall 20 comprises
thermal tubing 21, such as cross-linked polyethylene tubing (PEX),
for example AQUAPEX.RTM. available from Wirsbo Company of 4925 W
148th Street, Apple Valley Minn., 55124, USA, located within the
cavity of the partition wall 13. The tubing 21 is arranged in a
serpentine manner to distribute the tubing in the wall. The tubing
21 can be overlapped as necessary and without concern. Tubing 21
can be arranged in up-and-down orientation (not shown) or a
side-to-side orientation (shown) which can have advantages if the
system needs to be drained at come point. Thermal water is
circulated through the tubing 21 as necessary to meet the thermal
loads, typically heating and can alternately include cooling.
Heating loads for each suite 11a,11b . . . are provided from the
domestic hot water DHW provided at each floor. Where necessary,
cooling loads are provided from the domestic cold water DCW,
preferably chilled, provided at each floor. The length of thermal
tubing 21 fit to the radiant wall 20 provides sufficient surface
area to meet the design thermal loads as is known to those of skill
in the art.
[0031] Within a radiant wall 20, the thermal tubing 21 is
positioned sufficiently offset within the wall 20 from either wall
surface to avoid accidental punctures from screws and other
fasteners.
[0032] An implementation of various embodiments in the context of a
high rise building 30 is set forth in FIGS. 3A-3C and discussed
later below.
[0033] With respect to the radiant walls 20, and in FIG. 4, where
heating is desired only to one side of the radiant wall 20, such as
at a party wall 14, the wall 20 is configured for directing the
heat H into the room 10 only which is to be heated. Again, the
thermal tubing 21 is also positioned sufficiently offset within the
wall 11 from the wall surface to avoid accidental punctures from
screws and the like, however, heat transmission is emphasized from
one side of the wall 20, either through heat reflective surfaces,
offsetting the radiant tubing 21 more towards the wall surface
adjacent the room to be heated, or through selective insulation 15
or a combination thereof.
[0034] In FIG. 5, end suites are subject to greater heat loss
through windows and an additional exterior wall and can be fit with
additional thermal tubing 21, such as in an auxiliary radiant
heating loop 22. The loops 22 are embedded in the floor and provide
heat H adjacent the areas most susceptible to the additional heat
loss or gain due to exterior influences. The loop 22 can be in
plumbed to circulate in series with radiant wall 20, such as after
the thermal tubing 21 has passed through the radiant wall and
resulting in lesser thermal gradient. Depending on the plumbing
arrangement, alternatively the loop 22 can be plumbed in parallel
with the radiant wall for maximal output of heat H.
[0035] Domestic hot water DHW and domestic cold water DCW are also
typically provided at each floor of a multi-story building and are
circulated to each suite 11.
[0036] FIG. 3A is a schematic illustration of a typical arrangement
of piping for radiant walls 20 for a high rise, multi-story
building 30. At least a heating system 31 such as a boiler or heat
pump is provided for the heating and circulation of heated domestic
hot water DHW through a hot water supply riser HWS to each floor
33. Domestic hot water returns to the heating system 31 through a
hot water return riser HWR. The heating system can be located at a
convenient location. Hot water heaters and boilers with heat
exchangers for heating domestic hot water are often at roof level.
Heat pumps, which can heat or cool domestic water are typically
located in the basement levels adjacent ground loops.
[0037] The hot water supply riser HWS and hot water return riser
HWR extend to each of the multiple services floors 33 and are
fluidly connected to the hot water heating system 31. Water
pressure of the domestic hot water DHW in the risers HWS,HWR varies
with elevation due to the variation in hydrostatic head.
[0038] The heating system 31 is illustrated at the top floor but
could be located at any elevation in fluid communication with the
supply and return risers HWS,HWR.
[0039] Further, on very tall buildings, vertical zones of multiple
floors can be provided with their own heater, hot water supply and
return risers (not shown). The multiple serviced floors can be
arranged in vertical zones, further comprising for each zone a
booster pump which supplies water to the zonal hot and cold water
risers to ensure a pressure exists therein which, at a highest
floor of the zone is at least domestic service pressure, and at the
lowest floor of the zone, is at or below a maximum booster system
pressure.
[0040] Where cooling functions are desired, a cooling system 41
such as a heat pump or chiller is also provided for circulation of
chilled domestic cold water DCW through a chilled water supply
riser CWS to each floor 33. Domestic cold water returns to the
cooling system 41 through a chiller water return riser CWR. The
cooling system 41 is illustrated at the top floor but could be
located at any elevation along the supply and return risers
CWS,CWR. Water pressure of the domestic cold water in the risers
CWS,CWR varies with elevation. The temperature of the chilled water
is pre-determined to avoid condensation issues as is known to those
skilled in the art.
[0041] With reference to FIGS. 3A and 3C, each serviced floor 33
comprises a plurality of suites 11a,11b . . . serviced with
domestic cold water DCW and domestic hot water DHW, supplied by the
hot water distribution main HWM and cold water distribution main
CWM respectively. For illustrative purposes only, one suite 11a is
shown plumbed to the mains HWM,CWM. Further, for illustrative
purposes only, a pedestal sink 44 is provided in suite 11a as an
example of a domestic use fixture 42.
[0042] Characteristic of multi-story buildings 30, each successive
higher floor 33 experiences a corresponding loss of hydrostatic
head and water pressure. In order to provide water under sufficient
domestic service pressure P.sub.D to more than one vertically
arranged floor in the building, the hot water supply riser HWS is
pressurized, at lowest of the lower floors 33b, to a pressure
threshold P.sub.H, which is often greater than the desired domestic
use pressure P.sub.D, so that a minimum domestic pressure P.sub.L
can be maintained at a highest of the upper floors 33t. The
pressure threshold P.sub.H at the lowest of the lower floors 33b,
is typically at a pump pressure for delivering at least the minimum
domestic pressure P.sub.L to the upper floors 33t.
[0043] Similarly, the cold water supply riser CWS also extends
either up or down the building 30, and is subject to the same
variation in hydrostatic head and will operate at substantially the
same variable pressures. Accordingly, the lowest floors 33b are
supplied at the greatest pressure with water pressure diminishing
at higher elevations to the upper floors 33t which are supplied at
the lowest pressure P.sub.L.
[0044] Domestic facilities or fixtures 42, such as toilets, sinks
and laundry hook-ups have a maximum service pressure and preferably
operate at domestic service pressures P.sub.D. The fixtures plumbed
with domestic water will a preferred hot water threshold pressure
and a cold water threshold pressure. Usually the threshold
pressures for the DCW and DHC at the fixtures 42 is the same
domestic service pressure PD. As shown in FIGS. 6A and 6B typical
plumbing fixtures in a suite include a water closet or toilet WC
(DWC only), laundry L (DHW and DCW), shower SH (DHW and DCW) and a
sink SK (DHW and DCW).
[0045] The pressure of the domestic hot water DHW and domestic cold
water DCW in the risers HWS,CWS at lower floors 33b can be higher
that acceptable domestic service pressures P.sub.D. Accordingly,
the cold water DCW and the hot water DHW for these lower floors 33b
are pressure reduced at the fixtures 42. One or more hot water
pressure reducing valve 43 are at least provided at each suite 11
for reducing the pressure of the hot water DHW directed to plumbing
fixtures 42. The valve 43 is located between the hot water
distribution main HWM, which circulates heating water at full riser
pressure through radiant walls 20, and the fixtures 42, which are
fed at reduced domestic service pressures P.sub.D.
[0046] Upper floors 33t do not require pressure reduction as the
water pressure is already between the minimum pressure P.sub.L and
a preferred domestic service pressure P.sub.D. Accordingly, the
domestic plumbing fixtures 42 for upper floors 33t are directly
plumbed to the distribution main HWM at the full pressure of the
hot water supply riser HWS.
[0047] Further, in FIG. 6B, before the water returns from a
serviced floor 33, a thermal tubing 21 from the hot water
distribution main HWM can also be directed to ancillary, non-suite
areas such as stairwells 50. In this arrangement shown in FIGS. 6A
and 6B, and according to FIG. 3B in which cooling is not required,
the domestic cold water DCW is not circulated. Therefore, a
pressure reducing valve 43 need only be provided (not shown)
between the cold water supply riser CWS and the cold water
distribution main CWM as domestic cold water is only used for
domestic use fixtures 42. Accordingly, pressure reducing valves are
not needed, nor illustrated, between the cold water distribution
main CWM and a return riser, as there is no need for a cold water
return main or riser.
[0048] As discussed in co-pending application Ser. No. 10/851,349,
filed May 21, 2004 to Applicant, the entirety of which is
incorporated herein by reference, and discussed in the context of
the use of fan coils as the preferred heating and cooling
equipment, improved efficiencies and comfort are achieved using an
improved piping system by implementing hot water supply risers HWS
and hot water return risers HWR extending vertically up the
building with pressure reduction applied on a floor-by-floor basis
as necessary to accommodate domestic plumbing fixtures 42. Each
floor is supplied with a domestic hot water distribution main HWM
for providing domestic hot water service throughout the floor to
each suite 11. Even at the lower floors 33b, hot water recirculates
at full hydrostatic pressures between the hot water heating system
31 or boiler, the supply risers HWS, and each distribution main
HWM, so as to enable recirculation of return domestic hot water DHW
through the hot water return riser HWR to the hot water heating
system 31, the recirculation being performed without pumping.
Therefore, on each lower floor 33b, a plurality of hot water
pressure reducing valves 43 are provided, one at each suite 11 or
for one or more of the plumbing fixtures 42. Each pressure reducing
valve 43 reduces the pressure between the full pressure of the hot
water main HWM and the actual domestic use fixtures 42 at domestic
service pressures PD. At upper floors 33t, once the hydrostatic
pressure in the hot and cold water supply risers HWS, CWS reduces
to approximately 80-85 psig or less, pressure reducing valves 43 on
both hot and cold water respectively are no longer required.
[0049] As shown in FIG. 3B, in instances where cooling is not
required, the cooling system 41 for the domestic cold water DCW is
generally not required at all, and the domestic cold water DCW can
be pressure reduced with valves 43 at each lower floor 33b and a
cold water distribution main CWM for each lower floor 33b can
operate at domestic service pressures PD.
[0050] Returning to FIG. 3A, where cooling through radiant walls 20
is also an option, the cold water supply riser CWS supplies cold
water to a cold water distribution main CWM for circulation of cold
water to each suite on the floor 33. Again, for lower floors 33b,
pressure reducing valves 43 are provided between the cold water
distribution main CWM and the domestic use fixtures 42.
[0051] With reference also to FIG. 3C, domestic hot water and
domestic cold water is provided to radiant walls 20 in two adjacent
suites 11a,11b through the hot water distribution main HWM and cold
water distribution main CWM respectively. The two suites 11 shown
are located adjacent an end of a run of the distribution mains
HWM,CWM. In order to implement alternative heating or cooling
through the radiant walls 20, a first three way valve 45 is
provided for alternately connecting an inlet end of the thermal
tubing to the hot water distribution main HWM for heating the
radiant wall 20 and the cold water distribution main CWM for
cooling the radiant wall. Under thermostatic control, either hot
water DHW flows through the thermal tubing 21, or chilled water
flows through the thermal tubing 21. The thermally spent water
flows out a discharge end of the thermal tubing 21 for return to
one of the risers HWR,CWR. Preferably a second three way valve 46
alternately connects the discharge end of the thermal tubing to the
hot water return main HWRM while heating, and the cold water return
main CWRM while cooling. Both the first and second three-way valves
45,46 can be controlled by a conventional thermostatic controller
(not shown).
[0052] Circulation of hot water through the radiant walls 20 is
effective by directing hot water DHW to each radiant wall 20 from
the hot water distribution main HWM, and back to a collector main
or hot water return main HWRM. Generally the hot water return main
is arranged in a run parallel to the distribution main HWM and is
in fluid communication with the hot water return riser. The hot
water return main HWRM collects all the spent hot water collected
from the radiant walls 20 for return to the hot water return riser
HWR and the hot water heating system 31.
[0053] After having distributed hot water to all suites 11 on a
floor 33, it is also preferable to install a flow control valve 47
between the hot water distribution main HWM and the return riser
HWR. Preferably the flow control valve 47 is positioned between the
hot water distribution main HWM, at about a last suite of the one
or more suites in series, and the hot water return main HWRM. The
valve 47 can be set at about 1/2 USgpm to assure that there is a
continual flow and supply of domestic hot water in the distribution
main HWM on each floor and adjacent each suite 11. This is
important, especially in the summer months when no hot water is
being used for circulation through the radiant walls 20, so as to
provide hot water on demand to the fixtures 42. More preferably
(not shown), in the case of very large residential suites, a flow
control valve can be located (not shown) in each suite to assure
that the hot water reaches the suite's faucets in less time.
[0054] As shown in FIG. 3C, radiant walls 20 are both heated and
cooled. Pressure reducing valves 43 are positioned, in each suite
11a,11b, between the mains HWM,CWM and the fixtures 42 for the
particular suite 11. Accordingly, pressures need not be reduced for
use with the radiant wall 20.
[0055] Circulation of cold water through the radiant walls 20 is
effective by directing cold water to each radiant wall 20 from the
cold water distribution main CWM, and back to a collector main or
cold water return main CWRM. Generally the cold water return main
CWRM is arranged in a run parallel to the distribution main CWM and
is in fluid communication with the cold water return riser CWR. The
cold water return main HWRM collects all the spent cold water
collected from the radiant walls 20 for return to the cold water
return riser HWR and the cooling system 41.
[0056] The thermostatic control for the suite 11 can be fit with a
dump valve (not shown) to periodically permit flow therethrough to
minimize stagnation in low demand situations or, for simplicity,
can operate periodically even during usual demand situations.
[0057] In testing conducted in Calgary, Alberta, Canada, a system
was tested which utilized domestic hot water DHW for both domestic
use and heating of student residences using a radiant wall 20.
Heating of adjacent rooms 10a,10b was simulated using a radiant
wall 20 such as that arranged shown in FIG. 1. The radiant wall 20
was formed by threading plastic pipe as the thermal tubing 21
through the metal studs in the partition wall 13, with local
thermostatic control of the flow of hot water DHW to each
occupant's room. The testing investigated the adequacy of thermal
performance (including comfort and thermal output), durability of
building systems (include pipe, drywall, and paint lifetime), and
the significance of energy savings. The assessment determined that
the system met the above criteria.
[0058] More specifically test measurements show that a single
radiant wall 20, as tested, had a heating capacity of about 1500 W
(4500 Btu/hr), which is sufficient to offset losses from typical
residence rooms. It was recognized that end units and top floor
units would require additional heating. The heat capacity was
determined by calculating the heat transfer from the hot water
supply and return temperature differential, the water flow rate,
and the heat capacity of the water per unit volume. The industry
guide for comfort assessment is ASHRAE's Standard 55-2004, Thermal
Environmental Conditions for Human Occupancy. At Calgary, Alberta's
99% winter design temperature of -27.degree. C. or 17.degree. F.,
the proposed system, including window losses, maintained an
interior room temperature of 11.degree. C. (52.degree. F.), which
compared favorably to the minimum acceptable vertical surface
temperature of 10.degree. C. in terms of radiant asymmetry (ASHRAE
2004, p. 7).
[0059] The wall operating conditions were within conditions deemed
acceptable by drywall and paint manufacturers. Prior art piping
arrangements that have worn prematurely, having small hot water
return water legs, are not used in this system. Further, it was
found that it is easy to service radiant wall tubing relative to
prior art piping systems such as in-slab radiant piping, because
the tubing is enclosed within dry-walled areas.
[0060] The simulated system was tested with a hot water temperature
of 150.degree. F. (10.degree. F. or 5.5.degree. C. higher than the
design temperature) and the maximum interior wall temperature
temperatures observed was 118.degree. F. (48.degree. C.), which was
4.degree. C. (7.degree. F.) below the warranty limit. Drywall
warranties typically allow temperatures up to 125.degree. F. (or
51.5.degree. C.) on a regular basis. Applicant understands that
latex paints can be exposed to temperatures of up to 175.degree. F.
(80.degree. C.) without degradation.
[0061] The whole building simulation model was used to estimate
annual pump energy use with a conventional dual-piped domestic hot
water and building heating system. Pump energy was estimated to be
about 5% of total annual energy use. The annual cost saving was
estimated to be about 33%, worth about $7,000 CAD at current energy
prices. For a building with a local boiler plant, the 60.degree. C.
supply water temperature for the system allows a return water
temperature suitable to permit condensing boilers to operate in
condensing mode and attain efficiencies above 88%.
[0062] In the testing, the heated wall, at steady-state heat
output, had a surface temperature of about 26.degree. C., compared
with a known normal range of 18-29.degree. C. (65-85.degree. F.).
The supply-return temperature differential was a minimum of about
5.5.degree. C. The flow rate of the water through the wall was 1
USgpm or 0.063 L/s. At a density of 1,000 g/L, this is a mass flow
of 63 g/s. With the specific heat of water at 4.2 J/gC, the heat
transferred was 245 J/s per .degree. C. or 245 W/.degree. C. For a
6.degree. C. temperature differential (the approximate difference
at maximum heating), the heat transfer was then 1470 W (5000
Btu/hr). The heat loss was calculated for the double room, as its
wall area is greater. The heat loss was estimated at about 1320 W
at the design outdoor temperature with a temperature differential
inside to outside of -49.degree. C. The heat loss comprised 140W
from a spandrel area of 2.4 m.sup.2, 709 W from 5.4 m.sup.2 of
windows, 237W from 8.1 m.sup.2 of exterior wall, and lastly an
estimated loss from infiltration of 233W.
[0063] The wall heat supply was therefore greater than the wall
heat loss. The calculation neglected heat gains from occupants
(about 70W per person) and any heat-generating equipment, which
would provide an additional "cushion" against heat loss. A window
thermal gradient calculation showed that the interior temperature
at the -27.degree. C. design temperature is 11.degree. C.
[0064] While a preferred embodiment of the invention has been
illustrated and described, it will be appreciated that various
changes can be made therein without departing from the spirit and
scope of the invention. Consequently, within the scope of the
appended claims, it is to be understood that the invention can be
practiced otherwise than as specifically described herein.
* * * * *