U.S. patent application number 14/061031 was filed with the patent office on 2015-04-23 for multiple zone control system and method of operation.
This patent application is currently assigned to BURNHAM HOLDINGS, INC.. The applicant listed for this patent is BURNHAM HOLDINGS, INC., U.S. BOILER COMPANY, INC.. Invention is credited to Peter Michael CLOONAN, Christopher Read DREW.
Application Number | 20150108230 14/061031 |
Document ID | / |
Family ID | 52825299 |
Filed Date | 2015-04-23 |
United States Patent
Application |
20150108230 |
Kind Code |
A1 |
CLOONAN; Peter Michael ; et
al. |
April 23, 2015 |
MULTIPLE ZONE CONTROL SYSTEM AND METHOD OF OPERATION
Abstract
A multiple heating/cooling zone control system is disclosed. A
heating/cooling system control device continuously monitors
heating/cooling zone demand and matches the heating/cooling device
output capacity to the total space or heat input required. Within
the calculated heating/cooling device output capacity the
heating/cooling device is modulated based on zone temperature
setpoint to further adjust heating/cooling device output. As
heat/cooling loss is increased heating/cooling device capacity and
modulation are increased. Should heat/cooling loss decrease
heating/cooling device capacity and modulation are decreased. Since
heat/cooling output is adjusted based on the heat loss(gain) the
heating/cooling device can be immediately adjusted to the proper or
matching heating/cooling rate even before water/air temperature
based adjustments can be made. Hence, the overall effect of the
control device is a reduction in cycles of the heating/cooling
device and the life of the heating/cooling device is extended and
subsequent energy is saved.
Inventors: |
CLOONAN; Peter Michael;
(Lititz, PA) ; DREW; Christopher Read; (Lititz,
PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BURNHAM HOLDINGS, INC.
U.S. BOILER COMPANY, INC. |
Lancaster
Lancaster |
PA
PA |
US
US |
|
|
Assignee: |
BURNHAM HOLDINGS, INC.
Lancaster
PA
U.S. BOILER COMPANY, INC.
Lancaster
PA
|
Family ID: |
52825299 |
Appl. No.: |
14/061031 |
Filed: |
October 23, 2013 |
Current U.S.
Class: |
236/1B ; 165/209;
165/237; 165/257; 237/62; 237/8A |
Current CPC
Class: |
F24F 3/00 20130101; F24F
2110/12 20180101; F24F 2120/10 20180101; Y02B 30/70 20130101; F24F
11/70 20180101; F24D 19/1012 20130101; F24F 11/30 20180101; Y02B
30/745 20130101; F24D 19/1009 20130101; F24F 2110/10 20180101; F24D
2220/04 20130101 |
Class at
Publication: |
236/1.B ;
165/209; 165/237; 165/257; 237/8.A; 237/62 |
International
Class: |
F24F 11/00 20060101
F24F011/00; F24D 3/02 20060101 F24D003/02; F24D 19/10 20060101
F24D019/10; F24F 3/00 20060101 F24F003/00 |
Claims
1. A method for controlling a multiple zoned heating/cooling
system, the method comprising: establishing a heating/cooling
demand for multiple individual zones; communicating to a controller
active zones which require heating/cooling; summing the total
heating/cooling demand required by the active zones; establishing a
maximum heating/cooling rate based on the total heating/cooling
demand required by the active zones; establishing the type of
heating/cooling radiation type associated with heating/cooling
demand; communicating to the controller active heating/cooling
radiation type; establishing a target temperature setpoint based on
active heating/cooling radiation type; setting a heating/cooling
rate based on measured temperature, target temperature setpoint and
a maximum heating/cooling rate.
2. The method of claim 1 further comprising: adjusting the maximum
heating/cooling rate based on the requirements of the active zones
as the active zones vary.
3. The method of claim 1 further comprising: adjusting the
heating/cooling rate based on the output of a heating/cooling
device and the total heating/cooling demand required by the active
zones.
4. The method of claim 1 further comprising: establishing a maximum
zone run time for each individual zone; determining if a demand
time for any active zone exceeds the maximum zone run time;
adjusting a heating/cooling device capacity for the total
heating/cooling demand for all zones if the demand time for any
active zone exceeds the maximum zone run time.
5. The method of claim 1 further comprising: monitoring home
status, including time of day or occupancy; adjusting the target
temperature setpoint equal to the temperature setpoint for the
radiation type for the active zones based on the home status.
6. The method of claim 1 further comprising: monitoring outside
temperature; adjusting the target setpoint equal to the temperature
setpoint for the radiation type for the active zone based on the
outdoor temperature.
7. The method of claim 1 further comprising: establishing a set
period of time in which a respective zone must become active;
establishing a minimum fixed temperature; monitoring outside
temperature; causing warm water to flow through pipes of the
respective zone of the heating system if the respective zone has
not become active in a set time period and the outdoor temperature
is below minimum fixed temperature.
8. The method of claim 1 further comprising: displaying diagnostic
information regarding the heating/cooling system.
9. The method of claim 1 further comprising: displaying information
regarding individual zone status, individual zone total cycles
and/or system performance.
10. A method for controlling a multiple zoned boiler heating
system, the method comprising: establishing a heating demand
required for an amount of hot water flowing or for multiple
individual zones; establishing a maximum firing rate based on the
total heating demand required; setting the firing rate based on
measured temperature, the target water temperature setpoint and the
maximum firing rate.
11. The method of claim 10 further comprising: adjusting the
maximum firing rate of a boiler based on the active heat demand as
the active heat demand varies.
12. The method of claim 10 further comprising: adjusting the firing
rate of the boiler based on a heat output of the boiler and the
total heating demand required.
13. The method of claim 10 further comprising: establishing a
reduced firing rate maximum run time for maximum firing rate
reduced below boiler capacity; determining if the run time exceeds
the reduced firing rate maximum run time; adjusting the maximum
firing rate to boiler capacity if the demand time exceeds the
reduced firing rate maximum run time.
14. The method of claim 10 further comprising: monitoring home
status, including time of day or occupancy; adjusting the target
water temperature setpoint of the boiler based on the building
status.
15. The method of claim 10 further comprising: monitoring outside
temperature; adjusting the target water setpoint temperature of the
boiler based on the outdoor temperature.
16. The method of claim 10 further comprising: displaying
diagnostic information regarding the heating system.
17. The method of claim 16 further comprising: displaying
information regarding total heat demand or system performance.
18. A boiler control system comprising: at least one zone panel
with thermostats connected thereto, individual thermostats
monitoring individual zones; a boiler controller, the boiler
controller communicates with a boiler to control the operation of
the boiler; a communication bus extending between the at least one
zone panel and the boiler controller; the boiler controller
receives information from at least one zone panel, the boiler
controller sums the total heating demand required by the individual
zones which require heat and sets the water temperature setpoint
for the boiler and the firing rate for the boiler based upon the
total heating demand from the individual zones which require
heat.
19. The boiler control system as recited in claim 18, wherein the
communication bus is an ethernet cable which allows two way
communication between the at least one zone panel and the boiler
controller.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to a multiple zone
control system for controlling heating and/or air conditioning and
a method of operation thereof. In particular, the invention is
directed to the control and operation of multiple heating (cooling)
zones for single and multiple family residences.
BACKGROUND OF THE INVENTION
[0002] Boiler systems have been used to regulate the temperature of
commercial and residential facilities for a number of years.
However, despite the fact that boiler systems have been around for
many years, innovations continue to change the manner in which
these systems operate.
[0003] The first residential boilers were coal or wood fired and
were always "on". The resulting over or under heating was corrected
by opening a window, putting on a sweater and adding more or less
fuel the next day. Next the industry introduced the "on/off" boiler
that turned "on" the boiler when the home was cold and turned it
"off" after it became warm. A single thermostat sensed room
temperature at a single home position. The remainder of the home
was either cooler or warmer as a result. To solve this issue the
industry introduced multiple heating zones. This provided
individual rooms or groups of rooms with separate thermostats and
heated water was only circulated to where it was needed. This
innovation greatly improved home comfort, however, it sometimes
lead to a dramatically over sized heat source for when a small zone
calls for heat. The result was potentially excessive boiler
cycling. Boiler cycles add wear and tear on boiler, reduce
equipment life and waste energy. They also lead to less home
comfort as warm water is not consistently supplied. To address this
issue the industry introduced the modulating boiler. This boiler
could reduce British thermal unit (BTU) output when the demand was
from a smaller zone.
[0004] However, modulating boilers could only use water temperature
feedback to modulate the firing rate. When water temperature is
below setpoint the firing rate is increased to heat water and
increase water temperature until it matches the setpoint. This
method is aware of the amount of heat loss (heating load) only
after sensing the temperature and the rate of temperature change.
This method allows the system to overshoot and/or excessively cycle
as cold return water drives the firing rate to maximum modulation
even if only a small zone is calling. This problem is increased by
the fact that boilers are not sized (selected and installed) to
match the active load. Boilers actually cannot be sized to match
the active load. Boilers are sized to meet the total home heat
demand on a design day. Typical condensing boiler installations
have four water zones. When only one zone is calling for heat the
boiler is dramatically oversized for that demand. As a result, the
boiler first senses a low boiler supply temperature and fires the
boiler as if the entire home was calling. This initial response
produces unneeded and potentially excessive cycles.
[0005] It would be beneficial to provide a multiple zone control
system for controlling heating and/or air conditioning and a method
of operation thereof which is efficient and which eliminates
excessive wear and cycle of the heating/cooling unit.
SUMMARY OF THE INVENTION
[0006] An object of the invention is to provide a means to detect
active (turned "on") zones, totals BTUs required and sets the
heating/cooling firing rate to "match" actual home demand.
[0007] An object of the invention is to provide a heating/cooling
system which is able to satisfy each individual zone with the
appropriate amount of heat/cooling without extra cycles, component
life reduction or wasted energy.
[0008] An object of the invention is to provide adaptive firing
rate control. This type of control adds feed-forward to the
conventional temperature based feedback control system. This
control device calculates the boiler size required based on the
particular zone that is calling, a control technique called
"feed-forward" control. Before the boiler is even released to fire
the boiler, "size" is set to match the possible heat loss.
Temperature modulation is then used to adjust this firing rate
further to suit the active load. The control device optimizes
condensing boiler firing rate by preventing the firing rate from
driving too high based on measuring temperature alone. The result
is a significantly increased amount of time the boiler operates in
the condensing mode, reduced cycling, increasing equipment life and
saving fuel.
[0009] An embodiment is directed to a multiple heating zone control
system in which a boiler or stage is provided with heating BTU/hr
capacity required and water temperatures required. A heating system
control device continuously monitors heating zone demand and
matches the boiler output capacity to the total space or indirect
water heater heat input required. Within the calculated boiler
output capacity the boiler is modulated based on zone water
temperature setpoint to further adjust boiler heat output. As heat
loss is increased boiler capacity and modulation are increased.
Should heat loss decrease, boiler capacity and modulation are
decreased. Hence, the overall effect of the control device is a
reduction in boiler cycles, extended boiler life and subsequent
energy savings.
[0010] An embodiment is directed to a method for controlling a
multiple zoned heating/cooling system. The method includes:
establishing a heating/cooling demand for individual zones;
communicating to a controller active zones of the multiple zoned
heating/cooling system which require heating/cooling; summing the
total heating/cooling demand required by the active zones;
establishing a maximum heating/cooling rate based on the total
heating/cooling demand required by the active zones; establishing
the type of heating/cooling radiation type associated with
heating/cooling demand; communicating to the controller active
heating/cooling radiation type; establishing a target temperature
setpoint based on active heating/cooling radiation type; and
setting a heating/cooling rate based on measured temperature,
target temperature setpoint and a maximum heating/cooling rate.
[0011] An embodiment is directed to a method for controlling a
multiple zoned boiler heating system. The method includes:
establishing the heating demand for an amount of hot water flowing
or for individual heating zones; establishing a maximum firing rate
based on the total heating demand; setting the firing rate based on
measured temperature, the target water temperature setpoint and the
maximum firing rate.
[0012] An embodiment is directed to a boiler control system. The
boiler system includes at least one zone panel with thermostats
connected thereto, with individual thermostats monitoring
individual zones. A boiler controller communicates with a boiler to
control the operation of the boiler. A communication bus extends
between the at least one zone panel and the boiler controller. The
boiler controller receives information from the at least one zone
controller and sums the total heating demand required by the
individual zones which require heat. The boiler controller sets the
water temperature setpoint for the boiler and the firing rate for
the boiler based measured water temperature, target temperature
setpoint and the total heating demand required by the active
zones.
[0013] Other features and advantages of the present invention will
be apparent from the following more detailed description of the
preferred embodiment, taken in conjunction with the accompanying
drawings which illustrate, by way of example, the principles of the
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a diagrammatic schematic view of an illustrative
multi-zoned heating system according to the present invention.
[0015] FIG. 2 is a diagrammatic view of an illustrative embodiment
of zone panels and the boiler controller according to the present
invention.
[0016] FIG. 3 is a diagrammatic view of an illustrative embodiment
of the system control logic according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0017] The present invention will be described more fully
hereinafter with reference to the accompanying drawings, in which
illustrative embodiments of the invention are shown. In the
drawings, the relative sizes of regions or features may be
exaggerated for clarity. This invention may, however, be embodied
in many different forms and should not be construed as limited to
the embodiments set forth herein; rather, these embodiments are
provided so that this disclosure will be thorough and complete, and
will fully convey the scope of the invention to those skilled in
the art.
[0018] It will be understood that spatially relative terms, such as
"top", "upper", "lower" and the like, may be used herein for ease
of description to describe one element's or feature's relationship
to another element(s) or feature(s) as illustrated in the figures.
It will be understood that the spatially relative terms are
intended to encompass different orientations of the device in use
or operation in addition to the orientation depicted in the
figures. For example, if the device in the figures is turned over,
elements described as "over" other elements or features would then
be oriented "under" the other elements or features. Thus, the
exemplary term "over" can encompass both an orientation of over and
under. The device may be otherwise oriented (rotated 90 degrees or
at other orientations) and the spatially relative descriptors used
herein interpreted accordingly.
[0019] The present invention is directed to a system and method for
controlling heating and/or air conditioning which receives input
from multiple zones. The system includes multiple zones with
control inputs for receiving signals from individual thermostats to
sense individual zone demand. The system also includes control
outputs to provide heating or cooling to individual zones, i.e.
turn on water flow to individual zones.
[0020] Referring to FIG. 1, an illustrative multiple zoned heating
system 10 is shown. While the present invention is not limited to
multi-zoned heating systems, a multi-zoned heating system is used
for illustration. The system shown in FIG. 1 is used to control the
temperature in an enclosure 11 in which a first zone 12 and a
second zone 14 have been defined. While the illustrative embodiment
depicts two zones, additional zones may be provided, including but
not limited to, sixteen (16) total zones.
[0021] The system includes a boiler controller 20 which controls at
least one boiler 21 and separate zone controller/panel 22 connected
by a communication bus 24. The communication bus 24 allows two way
communication between the zone panel 22 and the boiler controller
20. In the embodiment shown, the communication bus 24 is a standard
ethernet cable with standard connectors 26 (FIG. 2), such as, but
not limited to RJ45 splitters.
[0022] In the embodiment shown, up to four (4) zone panels 22 may
be connected to the boiler controller 20 at one time using. Each
zone panel 22 may have up to four (4) zones, thereby allowing up to
sixteen (16) zones to be monitored by the boiler controller 20.
Each zone has a thermostat 29 to sense the heating demand for that
zone.
[0023] Additionally, a configurable communicating thermostat 30 may
be connected to the zone panel 22. The communicating thermostat 30
is "instanced" with an individual zone address. The communicating
thermostat 30 allows a user to program an appropriate temperature
range for each zone, as well as program various factors/inputs,
including, but not limited to time of day and occupancy of home.
Both the respective zone panel 22 and the boiler controller 20
receive input from the communicating thermostat 30. In addition to
the communicating with the zone panels 22, the boiler controller 20
can communicate and control additional inputs and outputs. In the
embodiment shown, twenty-four (24) additional inputs and outputs
can be used. Such inputs/outputs are used, for example, to
communicate with various sensors and to properly control the flow
of heated water to the required zones. While particular numbers of
zones, panels, thermostats, inputs and outputs, etc. are shown and
described with respect to the illustrative embodiments, the
invention is not limited to the numbers shown or described.
[0024] The boiler controller 20 may be, but is not limited to, an
integrated controller that includes a single PC board or a small
number of PC boards. The controller 20 may be housed in a single
enclosure or housing that can be easily accessed. Each zone panel
22 may be, but is not limited to, an integrated controller that
includes a single PC board or small number of PC boards. Each zone
panel 22 may be housed in a single enclosure or housing that can be
easily accessed.
[0025] In some embodiments, an outdoor air sensor 31 may provide
temperature information that the boiler controller 20 may use to
determine the appropriate boiler target temperature setpoint to
efficiently operate the boiler 21. For example, some boilers 21 are
designed to create an efficiency curve that relates supply water
temperature 32 to outdoor air temperature 31. The boiler controller
20 may use these curves (or may include information related to or
approximating these curves) to determine the target operating
temperature of the boiler 21 at a given outside air
temperature.
[0026] The boiler controller 20 may also capture information from
other sources, such as, but not limited to, a supply water 32
and/or return water sensor 33, which in the illustrative
embodiment, determines the temperature of water leaving the boiler
21 and in the system at or just before the boiler 21. The boiler
controller 20 may use this information to adjust the heat output of
the boiler 21. In addition, other sensors commonly used in the
industry may be provided to allow the boiler controller 20 to
properly operate the boiler 21 to allow the boiler 21 to provide
heat in an efficient manner.
[0027] In the illustrative embodiment shown, a first radiator or
heat dissipation unit or heat emitter 40 supplies heat into the
first zone 12, and a second radiator or heat dissipation unit 42
supplies heat into the second zone 14. A first water pump 44
controls whether water is forced through the first radiator or heat
dissipation unit 40 into the first zone 12, while a second water
pump 46 controls whether water is forced through the second
radiator or heat dissipation unit 42 into the second zone 14.
[0028] During operation of the illustrative zoned multi-source
system shown in FIG. 1, the boiler controller 20 may sense whether
either zone 12 and/or zone 14, which includes a thermostat 29,
indicates a call for heat. If there is a call for heat, the boiler
controller 20 will determine the total demand and will fire the
boiler and adjust the modulation rate according to the demand, as
will be more fully described below. The boiler controller 20 also
activates a water pump 50, and zone panel 22 selectively operates
water pump 44 and/or water pump 46 corresponds to the calling
zone(s) to allow the heat to be delivered to the active zone which
is calling for the heat. As will be more fully described below the
activation of the boiler 21, the heating or modulation rate and the
like may be adjusted based on the information that the boiler
controller 20 receives from the outdoor air sensor 31, supply
sensor 32, return sensor 33 or other appropriate
sensors/sources.
[0029] In some zoned systems, a multi-speed pump may be provided to
vary the amount of water that is forced through the system
depending on the number of calling zones. For example, the pump 50
may have two speeds and use a lower speed when only one zone is
calling for heat, and a higher speed when two or more zones are
calling for heat.
[0030] Referring to FIG. 2, an illustrative control system 11 is
shown diagrammatically. The system includes a boiler controller 20
which controls at least one boiler 21 and separate zone
controller/panels 22 connected by a communication bus 24. The
communication bus 24 allows two way communication between the zone
panels 22 and the boiler controller 20. In the embodiment shown,
the communication bus 24 is one or more standard ethernet cables
with standard connectors 26, such as, but not limited to RJ45
connectors and/or splitters. In the embodiment shown, two (2) zone
panels 22 are connected to the boiler controller 20. One zone panel
has four (4) conventional thermostats 29. The other zone panel has
three (3) conventional thermostats 29 and a configurable
communicating thermostat 30. As discussed above, the communicating
thermostat 30 is "instanced" with an individual zone address. Both
the zone panel 22 and boiler controller 20 read this address and
the information programmed into the communicating thermostat. While
two zone panels 22 and eight thermostats 29,30 are shown, other
numbers of panels 22 and thermostats 29, 30 may be used without
departing from the scope of the invention. For example, four (4)
zone panels 22 may be connected to the boiler controller 20 at one
time using the communication bus or busses 24.
[0031] The boiler controller 20 controls the boiler 21, as will be
more fully described below. The boiler controller 20 also controls
blowers, fuel valves, pumps or other items associated with the
proper operation of the boiler 21. A display panel 60, such as, but
not limited to, an LCD display is provided to provide information
to the operator. In the embodiment shown, the display panel 60 is
provided on the boiler; however, the display panel 60 may be
located away from the boiler 21.
[0032] The boiler controller 20 may also control several water
pumps, including pumps for individual zones as required. The pumps
control the flow of heated water to the individual zones. The pumps
may be of any suitable type for use in an HVAC system. As
previously described with respect to FIG. 1, the boiler controller
20 may also receive information from an outdoor temperature sensor,
a humidity sensor, and/or any other type of sensor.
[0033] To help determine whether the heating source/boiler 21 is
capable of providing sufficient heat to satisfy the expected
heating load of the zone(s) that are currently calling for heat,
reference may be made to information relating to an estimated
heating load of each of the zones and information relating to an
estimated heating capacity of the heating source. The estimated
heating load of the zone(s) that are currently calling for heat
(active zones) as well as the estimated heating capacity of the
heating source may depend on the outdoor air temperature and/or the
outdoor air humidity.
[0034] Individual zones are monitored by the boiler controller 20.
When an individual zone is active a heat loss, as described above,
associated with that zone is "switched in" or recognized by the
thermostat 29 and communicated through the respective zone panel 22
to the boiler controller 20. When "switched in" or active, that
zone's heat loss is added together with the heat loss associated
with other active zones. The total heat loss summation associated
with active zones is compared with the maximum and minimum
allowable boiler capacity. Once calculated, this heat loss
summation is used to set the boiler's 21 maximum modulation rate.
As the boiler 21 is released to modulation the boiler controller
senses the boiler water temperature and compares the sensed water
temperature to the information that the boiler controller 20
receives from the active type dissipation unit or heat emitter, the
outdoor air sensor 30, supply sensor 32, return sensor 33 or other
appropriate sensors and sets a firing rate. This firing rate is now
limited to the heat capacity required by the active zones.
[0035] The maximum heating or modulation rate and setpoint varies
as different zones are "switched in" and the water target setpoint
varies as different types of heat emitters are active. Therefore,
the boiler controller 20 continually monitors and communicates with
the zone panels 22 and adjusts the setpoint and maximum modulation
rate based on the changing demands received from the thermostats
29, 30.
[0036] If a zone panel 22 loses communication with the boiler
controller 20 the maximum heat loss associated with that zone panel
22 is used as the default when setting the maximum modulation for
boiler firing. If all zone panels 22 lose communication with the
boiler controller 20 the maximum heat loss associated with all zone
panels 22 is used as the default when setting the maximum
modulation for boiler firing. This insures that sufficient heat
will be provided to the home in case of a fault. Therefore, a fault
or failure in communication results in the boiler using the maximum
allowable boiler capacity to set the modulation rate, which is the
equivalent to a conventionally heated home.
[0037] In addition to supplying heat, the system and method can be
used to supply domestic hot water demand to a hot water tank 62
(FIG. 1). In this arrangement, the hot water demand is treated as
another zone. Therefore, when priority for hot water is not
demanded or selected, the heating requirement for the hot water
zone is added together with the other active heating zones. The
total heat loss summation associated with active zones, including
the hot water zone, is used to set the boiler's 21 maximum
modulation rate. As the boiler 21 is released to modulation the
boiler controller senses the boiler water temperature and compares
the sensed water temperature to the information that the boiler
controller 20 receives from the outdoor air sensor 30, supply
sensor 32, return sensor 33 or other appropriate sensors/sources
and sets a firing rate. This firing rate is now limited to the heat
capacity required by the active zones.
[0038] However, if hot water is a priority, the hot water zone
indicates the same. This allows the hot water zone to remain active
and the other heating zones to be turned off. Under such
circumstances, the maximum modulation of the boiler is set to the
domestic hot water maximum modulation. This allows the boiler to be
sized to suit the domestic hot water demand. The domestic hot water
demand may be wired to either the boiler's or zone panel's domestic
hot water demand terminals.
[0039] The water setpoint may be based on various factors/inputs,
including, but not limited to individual zone demand, time of day,
occupancy of home and outside air temperature.
[0040] In operation, various methods can be used to impact heat
delivery. The following is a listing of exemplary methods for
impacting heat delivery when the zone panels and the boiler
controller described above are used. The methods recited are not
meant as an exhaustive listing, as other methods to impact heat
delivery may be used. While the exemplary methods are described
below as a series of acts or events, it will be appreciated that
the present invention is not limited by the illustrated ordering of
such acts or events. For example, some acts may occur in different
order and/or concurrently with other acts or events apart from
those illustrated and/or described herein, in accordance with the
invention. In addition, not all illustrated steps may be required
to implement a methodology in accordance with the present
invention. In addition, the illustrative methods are not meant to
be mutually exclusive. Many or all of the methods may be used
together.
[0041] A first illustrative method of impacting heat delivery is to
adjust the maximum heating/firing rate based on the heating
requirements of the active zones. In this process, the zone panels
are programmed to reflect the heat loss associated with each
individual zone. The boiler controller monitors the individual
zones and determines which zones are active and require heat. The
boiler controller then sums the heat loss of all active zones to
calculate the total heat loss measured. The boiler controller
calculates the heat output of the boiler based on blower rpm or
pump speed. The boiler controller sets the actual heating/firing
rate based on the heat output of the heating device and the
measured heat loss. Variables which influence the firing rate
include, but are not limited to, the measured temperature, the
target water temperature set point and the maximum firing rate of
the system. As the boiler controller continually monitors the
system the controller recalculates demand as the active zone
changes.
[0042] A second illustrative method of impacting heat delivery is
based on the particular zone or zones that are active (or calling
for heat). In this process, the zone panels are programmed to
reflect the radiation type associated with each individual zone.
Setpoints are programmed/established for up to three radiation
types. For example, in a sixteen (16) zone system, zones 1, 2 or
5-16 may have first setpoint, zone 3 may have a second setpoint and
zone 4 may have a third setpoint. The boiler controller monitors
the individual zones and determines which zones are active and
require heat. The boiler controller sets the boiler water target
temperature based on the active heat demand type. The boiler
controller modulates the boiler to reach this target while
remaining below maximum heating/firing rate.
[0043] A third illustrative method of impacting heat delivery is to
adjust heat loss based on individual zone call duration. In this
process, a maximum zone run time is established and programmed into
the boiler controller or the zone panel. The demand time is field
adjustable. If the demand time exceeds the maximum zone run time,
the boiler controller releases the boiler to maximum fire. The
system has an ability to adjust boiler capacity for the total heat
capacity of the home, maximum central heat demand or total heat
capacity for domestic hot water, maximum domestic hot water demand.
When the duration of any zone within these categories has exceeded
the maximum zone run time the boiler capacity is released to the
maximum for that category. This allows the system to adapt to
changing conditions, such as, but not limited to, changes which
effect zone heat loss, such as open windows or doors.
[0044] Alternatively, a reduced firing rate maximum run time for
maximum firing rate reduced below boiler capacity may be
established. If the actual run time exceeds the reduced firing rate
maximum run time, the firing rate is adjusted to the maximum firing
rate to boiler capacity.
[0045] A fourth illustrative method of impacting heat delivery is
to adjust heat based on home status, such as, but not limited to,
time of day and occupancy. In this process, the boiler controller
communicates with and receives input from a
communicating/programmable thermostat. The boiler controller
adjusts the water temperature setpoint based on time of day and
occupancy feedback from the thermostat.
[0046] A fifth illustrative method of impacting heat delivery is to
adjust heat based on the outdoor temperature. In this process, the
outdoor temperature is monitored and communicated to the boiler
controller and/or the zone panels. Based on the outdoor
temperature, each zone's setpoint temperature may be adjusted.
[0047] A sixth illustrative method of impacting heat delivery
provides frost protection. In this process, the zone activity of
each zone is monitored by the boiler controller or a zone panel.
The outdoor air temperature is also monitored by the boiler
controller or a zone panel. If it is determined that a particular
zone has not operated in a set time period, i.e. one hour, and the
outdoor temperature is below a set temperature, i.e. zero degrees
Fahrenheit, the zone is activated, causing an individual zone pump
and a primary pump to start, allowing warm water to move into the
zone, thereby providing frost protection by preventing the water
pipes from freezing. This will move warm water into a zone that may
have a failed or poorly located thermostat. In this process, a zone
is activated even when the thermostat is not requesting heat to
protect from freezing.
[0048] A seventh illustrative method of impacting heat delivery
provides diagnostic information to the user or service technician.
Information regarding individual zones and system performance, such
as, but not limited to, zone cycles counts, zone status, zone heat
loss, zone alarms and other relevant information can be stored in
the boiler controller or the zone panels. The information can be
accessed using diagnostic equipment or through the display panel on
the boiler. The information may be used to diagnose problems and to
adjust various settings, including, but not limited to, thermostat
settings, zone groupings or heat loss settings, to maximize the
efficiency of the heating system and/or the users comfort.
[0049] The method and system described herein has many benefits.
One such benefit is minimized cycling of the boilers. As the zone
panels are continually communicating with the boiler controller,
the boiler or boilers are started and stay running in response to
the changing demand. This avoids wear and tear and standby
losses.
[0050] Another benefit is that the firing rate is kept low or
minimized. Allowing for a low firing rate enables the heating
system to operate at a high efficiency operation. In addition, due
to the minimized cycling and low firing rate, a steady, even heat
is delivered, thereby increasing home comfort while maximizing
efficiency. For example, when a home has a 150 kbtu boiler
installed, using known or conventional technology and systems, the
boiler is normally released with a boiler size of 150 k BTU. A
conventional control would drive the boiler to high fire (150 k
BTU) in response to measure supply temperature and the rate of rise
of supply temperature and begin to reduce the firing rate only
after supply temperature begins to rise. In contrast, when the
system and method of the current invention is used and a 40 k BTU
zone is calling for heat the boiler is sized to be 40 k BTU. The
boiler then modulates between minimum modulation and 40 k BTU to
satisfy the demand. The boiler is not driven to fire at 150 k
BTU.
[0051] The use of the zone panels and boiler controller which allow
for standard ethernet cable allows for easy installation for new
and existing systems. This eliminates line and low voltage wiring
between zone controls and the boiler control that is required in
known systems.
[0052] Referring to FIG. 3, the active boiler maximum modulation 70
is the maximum boiler modulation rate required to satisfy the
active heat demand. This value is the combination of maximum heat
loss from low temperature heating zones 71, high temperature
heating zones 72 and domestic hot water heating zone 73. Domestic
hot water heat zones 73 are added to the central heating zones or
replace the central heating zone heat loss based on the priority
selection 74 and priority timer 75 value. The low temperature
heating zones heat loss and high temperature heating zones heat
loss are subsets of the central heating maximum heat loss. Both the
central heating and domestic hot water heat loss are compared with
the boiler maximum 76 and boiler minimum 77 modulations. Upon loss
of communication 78 the boiler control sets heat loss equal to the
boiler maximum modulation 76. Active zone demand time is monitored.
If any active zone demand time exceeds the zone release time 79 the
active boiler maximum modulation is set to the boiler maximum
modulation. The boiler controller senses the boiler water
temperature and compares the sensed water temperature to the target
temperature setpoint further adjust firing rates for each boiler
within the calculated maximum modulation rate. Target temperature
setpoint is based on the type of dissipation units or heating
elements. Separate setpoints are established for low temperature,
high temperature and domestic hot water heating zones. These target
temperature setpoints are further adjusted based on home status,
including time of day or occupancy, outdoor air temperature and
other settings. Individual zone status is used to develop a field
resettable individual zone cycle count. The cycle count is used to
alert an installing contractor to mechanical or electrical issues
with the heating system.
[0053] In applications in which multiple boilers are used to
provide heat, the boiler controller 20 performs the same functions
as above to determine total required boiler heat capability
required. However, instead of individual zone demands, the control
may use other methods to obtain heat demand, such as, but not
limited to, system pump speed, system differential temperature,
system differential pressure. The boiler controller 20 fires
required boilers to match the heat loss. The boiler controller
senses the boiler water temperature and compares the sensed water
temperature to the setpoint further adjust firing rates for each
boiler within the calculated maximum modulation rate.
[0054] The system and method disclosed herein is described with
reference to an exemplary boiler heating system. However, the
system and method is applicable and can be used with other types of
heating systems, including, but not limited to heat pumps or
furnaces. The system and method is applicable and can be used with
cooling systems and other types of air conditioning systems. In
addition, the system and method can be with heating or cooling
systems which have one or more heating or cooling sources.
[0055] In general, the method described herein is for controlling a
multiple zoned heating/cooling system. The method includes:
communicating to a controller individual active zones of the
multiple zoned heating/cooling system which require
heating/cooling; establishing the heating/cooling demand size for
the active zones; summing the total heating/cooling demand size
required by the active zones; establishing a maximum firing/cooling
rate for a heating/cooling device based on the total
heating/cooling demand required by the active zones; and setting a
temperature setpoint for a heating/cooling device based on outside
air sensor 30, supply sensor 32, return sensor 33 or other
appropriate sensors. This firing rate/cooling rate is now limited
to the heat capacity required by the active zones.
[0056] While the invention has been described with reference to a
preferred embodiment, it will be understood by those skilled in the
art that various changes may be made and equivalents may be
substituted for elements thereof without departing from the spirit
and scope of the invention as defined in the accompanying claims.
In particular, it will be clear to those skilled in the art that
the present invention may be embodied in other specific forms,
structures, arrangements, proportions, sizes, and with other
elements, materials, and components, without departing from the
spirit or essential characteristics thereof. One skilled in the art
will appreciate that the invention may be used with many
modifications of structure, arrangement, proportions, sizes,
materials, and components and otherwise, used in the practice of
the invention, which are particularly adapted to specific
environments and operative requirements without departing from the
principles of the present invention. The presently disclosed
embodiments are therefore to be considered in all respects as
illustrative and not restrictive, the scope of the invention being
defined by the appended claims, and not limited to the foregoing
description or embodiments.
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