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JohnW January 23rd 05 08:37 PM

heat pump/secondary propane furnace questions
 
I have a lot to ask her but thought it's worth a shot. It has to do with
the house not heating well.

Last August we moved into a single family home (2 years old), which has a
number of heating/cooling systems.

The upper floor has a heat pump, presumably in the attic. When we had the
home inspected I followed the guy into the attic where he pointed out the
unit. My assumption is that this unit handles the heating/cooling of the
2nd story. It has a thermostat in the master bedroom and appears to work
fine when the outside temp is above 20 degrees or so. I'm not worried about
this system.

The main floor and basement are handled by several systems, and it's here I
have questions. There are two units outside, one of which appears to be a
dedicated air conditioner and a second unit that's a heat pump. We also
have propane furnace/air handler. These units were controlled by a
mercury-based manual thermostat, but I replaced it with a Honeywell RTH7400D
programmable thermostat using the same wires (4 wires: g,w,y,r). For what
it's worth, the propane also provides the heated water and a gas fireplace.

Here are the questions:

1. Is the heat pump the primary heat source and the propane secondary, or
the opposite? The inspection report calls the propane the primary source,
but that doesn't seem right, and the seasonal contractor we had inspect the
unit recently said the propane "appeared" to be the secondary. If it's not
all that cold outside, the heat pump is on, but not the propane, for
example. Today, at 16 degrees, both units run. And struggles to maintain
70.

2. The thermostat required a setup before programming the 7 days of the
week. One of the steps was choosing the heating/cooling system. There are
10 choices:
- heating and cooling (conventional)
- single stage heat pump with no backup or auxilliary heat
- heat only with no fan (conventional)
- heat only with fan (conventional)
- hot water heat only (conventional)
- Cool only (conventional)
- multistage heat pumps
- multistage conventional heating and cooling (2 stages heat and 2 stages
cool: requires w/w2 and y/y2 wires)
- multistage conventional heating and cooling (2 stages of heat and 1 stage
cool)
- multistage conventional heating and cooling (1 stage heat and 2 stages of
cool)

Right now I have it on the first setting.

3. What are the "stages" regarding heating systems as referred to above? My
assumption is that a heat pump with emergency/auxilliary heat is a
multistage heat pump (like the one in our attic for the second floor) but
does it also refer to a secondary heating source like natural gas, oil or
propane? If I had a W2 wire I suspect the 9th choice would be the most
appropriate but I just had the 4 wires mentioned above. After calling
Honeywell, the person agreed that the first choice seemed the most
appropriate.

4. I have heard twice now that heat pump/propane heat systems work just fine
if you leave the temperature constant throughout the day/week, but have
trouble with "recovery" when you let it dip in the evening and try to reheat
in the morning when everyone rises. This seems to be the problem with these
systems and programmable thermostats. Today I programmed every day and
every "event" to the same temp to see if this pans out over the next few
days.

I AM going to get the HVAC contractor out here again, at my expense, to pick
his brain in person, since I wasn't at home when he did the initial
inspection for us. However, any insight to the above beforehand would be of
great help. Thanks in advance.

John



Travis Jordan January 23rd 05 08:56 PM

"JohnW" wrote in message
...
The upper floor has a heat pump, presumably in the attic. When we had the
home inspected I followed the guy into the attic where he pointed out the
unit. My assumption is that this unit handles the heating/cooling of the
2nd story. It has a thermostat in the master bedroom and appears to work
fine when the outside temp is above 20 degrees or so. I'm not worried

about
this system.


A heat pump is just a reverse-cycle air conditioner. In your case it the
air handler is in the attic - but the compressor for the AC / heat pump is
outside.

There are two units outside, one of which appears to be a
dedicated air conditioner and a second unit that's a heat pump.


Nope, they are both condensers, used in conjunction with your inside air
handlers. Likely one or both are also capable of reverse cycle (a heat
pump).

We also
have propane furnace/air handler. These units were controlled by a
mercury-based manual thermostat, but I replaced it with a Honeywell

RTH7400D
programmable thermostat using the same wires (4 wires: g,w,y,r). For what
it's worth, the propane also provides the heated water and a gas

fireplace.

G - Fan
W - Heat (1st stage)
Y - Cool (1st stage)
R - Power

Here are the questions:

1. Is the heat pump the primary heat source and the propane secondary, or
the opposite? The inspection report calls the propane the primary source,
but that doesn't seem right, and the seasonal contractor we had inspect

the
unit recently said the propane "appeared" to be the secondary. If it's

not
all that cold outside, the heat pump is on, but not the propane, for
example. Today, at 16 degrees, both units run. And struggles to maintain
70.


Most commonly the heat pump is primary (1st stage) and the propane would be
secondary (2nd stage). Are you sure the old thermostat didn't have another
wire for second stage heat? It could be that the furnance controller
handles calling for the 2nd stage, but that is unusual.

2. The thermostat required a setup before programming the 7 days of the
week. One of the steps was choosing the heating/cooling system. There

are
10 choices:
- heating and cooling (conventional)
- single stage heat pump with no backup or auxilliary heat
- heat only with no fan (conventional)
- heat only with fan (conventional)
- hot water heat only (conventional)
- Cool only (conventional)
- multistage heat pumps
- multistage conventional heating and cooling (2 stages heat and 2 stages
cool: requires w/w2 and y/y2 wires)
- multistage conventional heating and cooling (2 stages of heat and 1

stage
cool)
- multistage conventional heating and cooling (1 stage heat and 2 stages

of
cool)

Right now I have it on the first setting.


Makes sense with only four wires. Are you SURE there wasn't a fifth wire?

3. What are the "stages" regarding heating systems as referred to above?

My
assumption is that a heat pump with emergency/auxilliary heat is a
multistage heat pump (like the one in our attic for the second floor) but
does it also refer to a secondary heating source like natural gas, oil or
propane? If I had a W2 wire I suspect the 9th choice would be the most
appropriate but I just had the 4 wires mentioned above. After calling
Honeywell, the person agreed that the first choice seemed the most
appropriate.


If you have aux / emergency heat strips then it is a 2-stage heat system
(NOT a multistage heat pump, which is a different animal). Of course you
COULD have both a multistage heat pump AND aux / emergency heat, but that is
uncommon.

4. I have heard twice now that heat pump/propane heat systems work just

fine
if you leave the temperature constant throughout the day/week, but have
trouble with "recovery" when you let it dip in the evening and try to

reheat
in the morning when everyone rises. This seems to be the problem with

these
systems and programmable thermostats. Today I programmed every day and
every "event" to the same temp to see if this pans out over the next few
days.


Ignore what you are hearing. ANY setback saves energy. Google for more
information on this widely misunderstood topic.

I AM going to get the HVAC contractor out here again, at my expense, to

pick
his brain in person, since I wasn't at home when he did the initial
inspection for us. However, any insight to the above beforehand would be

of
great help. Thanks in advance.


Good idea.



JohnW January 23rd 05 11:04 PM

Travis, thanks so much for your response.

After reading through it, I trudged back out in the snow to look at both
outside units. They both, are indeed, heat pumps for both cooling. You
know what they say about "assume". However, if this is the case, the one
unit I had assumed was a/c only HAS NEVER come on for heating since
installing the programmable thermostat. I also looked at the old manual
thermostat and there is no LED indicator that lights up when aux or
Emergency heat is on: note however, there is on the manual thermostat that
is in the upstairs bedroom.

I also pulled the front piece of the programmable thermostat and looked at
the wires again. The old thermostat only had 4 wires attached (g, y, w,
r--trust me, I actually took notes while doing this--but I noticed a blue
and black wire coiled up in the wall. I guarantee these were not connected
when I did the swap.

As an experiment, I put the face plate back on and pulled up the
thermostat's setup menu where the heating/cooling system is to be selected
and again browsed through the choices (note I've added details for the 7th
item in parenthesis as written in the manual):

1 heating and cooling (conventional)
2 single stage heat pump with no backup or auxilliary heat
3 heat only with no fan (conventional)
4 heat only with fan (conventional)
5 hot water heat only (conventional)
6 Cool only (conventional)
7 multistage heat pumps (heat pump with auxilliary or backup heat)
8 multistage conventional heating and cooling (2 stages heat and 2 stages
cool: requires w/w2 and y/y2 wires)
9 multistage conventional heating and cooling (2 stages of heat and 1
stage cool)
10 multistage conventional heating and cooling (1 stage heat and 2 stages of
cool)

I changed the setting from 1 to 7 and the other heat pump can on
immediately! It cycles off and on periodically as it maintains 70 degrees.
However, now the propane shut off, which always seemed to be running before.
I assume it's safe to keep the setting on 7, and I should check this after
sundown and tomorrow morning and see if the propane is coming on to
supplement the heat pump. I'm still going to get a service tech out here to
double check everything, but the setup as we had it couldn't be right.

Live and learn.

Thanks again, Travis...

John

"Travis Jordan" wrote in message
...
"JohnW" wrote in message
...
The upper floor has a heat pump, presumably in the attic. When we had
the
home inspected I followed the guy into the attic where he pointed out the
unit. My assumption is that this unit handles the heating/cooling of the
2nd story. It has a thermostat in the master bedroom and appears to work
fine when the outside temp is above 20 degrees or so. I'm not worried

about
this system.


A heat pump is just a reverse-cycle air conditioner. In your case it the
air handler is in the attic - but the compressor for the AC / heat pump is
outside.

There are two units outside, one of which appears to be a
dedicated air conditioner and a second unit that's a heat pump.


Nope, they are both condensers, used in conjunction with your inside air
handlers. Likely one or both are also capable of reverse cycle (a heat
pump).

We also
have propane furnace/air handler. These units were controlled by a
mercury-based manual thermostat, but I replaced it with a Honeywell

RTH7400D
programmable thermostat using the same wires (4 wires: g,w,y,r). For
what
it's worth, the propane also provides the heated water and a gas

fireplace.

G - Fan
W - Heat (1st stage)
Y - Cool (1st stage)
R - Power

Here are the questions:

1. Is the heat pump the primary heat source and the propane secondary, or
the opposite? The inspection report calls the propane the primary
source,
but that doesn't seem right, and the seasonal contractor we had inspect

the
unit recently said the propane "appeared" to be the secondary. If it's

not
all that cold outside, the heat pump is on, but not the propane, for
example. Today, at 16 degrees, both units run. And struggles to
maintain
70.


Most commonly the heat pump is primary (1st stage) and the propane would
be
secondary (2nd stage). Are you sure the old thermostat didn't have
another
wire for second stage heat? It could be that the furnance controller
handles calling for the 2nd stage, but that is unusual.

2. The thermostat required a setup before programming the 7 days of the
week. One of the steps was choosing the heating/cooling system. There

are
10 choices:
- heating and cooling (conventional)
- single stage heat pump with no backup or auxilliary heat
- heat only with no fan (conventional)
- heat only with fan (conventional)
- hot water heat only (conventional)
- Cool only (conventional)
- multistage heat pumps
- multistage conventional heating and cooling (2 stages heat and 2
stages
cool: requires w/w2 and y/y2 wires)
- multistage conventional heating and cooling (2 stages of heat and 1

stage
cool)
- multistage conventional heating and cooling (1 stage heat and 2 stages

of
cool)

Right now I have it on the first setting.


Makes sense with only four wires. Are you SURE there wasn't a fifth wire?

3. What are the "stages" regarding heating systems as referred to above?

My
assumption is that a heat pump with emergency/auxilliary heat is a
multistage heat pump (like the one in our attic for the second floor) but
does it also refer to a secondary heating source like natural gas, oil or
propane? If I had a W2 wire I suspect the 9th choice would be the most
appropriate but I just had the 4 wires mentioned above. After calling
Honeywell, the person agreed that the first choice seemed the most
appropriate.


If you have aux / emergency heat strips then it is a 2-stage heat system
(NOT a multistage heat pump, which is a different animal). Of course you
COULD have both a multistage heat pump AND aux / emergency heat, but that
is
uncommon.

4. I have heard twice now that heat pump/propane heat systems work just

fine
if you leave the temperature constant throughout the day/week, but have
trouble with "recovery" when you let it dip in the evening and try to

reheat
in the morning when everyone rises. This seems to be the problem with

these
systems and programmable thermostats. Today I programmed every day and
every "event" to the same temp to see if this pans out over the next few
days.


Ignore what you are hearing. ANY setback saves energy. Google for more
information on this widely misunderstood topic.

I AM going to get the HVAC contractor out here again, at my expense, to

pick
his brain in person, since I wasn't at home when he did the initial
inspection for us. However, any insight to the above beforehand would be

of
great help. Thanks in advance.


Good idea.





JohnW January 23rd 05 11:37 PM

I take it back. On setting 7, the heat pump comes on but nothing will
trigger the propane. Interestingly, I replaced the OLD thermostat, and the
propane comes on, but NOT the heat pump. What the hell...

John

"Travis Jordan" wrote in message
...
"JohnW" wrote in message
...
The upper floor has a heat pump, presumably in the attic. When we had
the
home inspected I followed the guy into the attic where he pointed out the
unit. My assumption is that this unit handles the heating/cooling of the
2nd story. It has a thermostat in the master bedroom and appears to work
fine when the outside temp is above 20 degrees or so. I'm not worried

about
this system.


A heat pump is just a reverse-cycle air conditioner. In your case it the
air handler is in the attic - but the compressor for the AC / heat pump is
outside.

There are two units outside, one of which appears to be a
dedicated air conditioner and a second unit that's a heat pump.


Nope, they are both condensers, used in conjunction with your inside air
handlers. Likely one or both are also capable of reverse cycle (a heat
pump).

We also
have propane furnace/air handler. These units were controlled by a
mercury-based manual thermostat, but I replaced it with a Honeywell

RTH7400D
programmable thermostat using the same wires (4 wires: g,w,y,r). For
what
it's worth, the propane also provides the heated water and a gas

fireplace.

G - Fan
W - Heat (1st stage)
Y - Cool (1st stage)
R - Power

Here are the questions:

1. Is the heat pump the primary heat source and the propane secondary, or
the opposite? The inspection report calls the propane the primary
source,
but that doesn't seem right, and the seasonal contractor we had inspect

the
unit recently said the propane "appeared" to be the secondary. If it's

not
all that cold outside, the heat pump is on, but not the propane, for
example. Today, at 16 degrees, both units run. And struggles to
maintain
70.


Most commonly the heat pump is primary (1st stage) and the propane would
be
secondary (2nd stage). Are you sure the old thermostat didn't have
another
wire for second stage heat? It could be that the furnance controller
handles calling for the 2nd stage, but that is unusual.

2. The thermostat required a setup before programming the 7 days of the
week. One of the steps was choosing the heating/cooling system. There

are
10 choices:
- heating and cooling (conventional)
- single stage heat pump with no backup or auxilliary heat
- heat only with no fan (conventional)
- heat only with fan (conventional)
- hot water heat only (conventional)
- Cool only (conventional)
- multistage heat pumps
- multistage conventional heating and cooling (2 stages heat and 2
stages
cool: requires w/w2 and y/y2 wires)
- multistage conventional heating and cooling (2 stages of heat and 1

stage
cool)
- multistage conventional heating and cooling (1 stage heat and 2 stages

of
cool)

Right now I have it on the first setting.


Makes sense with only four wires. Are you SURE there wasn't a fifth wire?

3. What are the "stages" regarding heating systems as referred to above?

My
assumption is that a heat pump with emergency/auxilliary heat is a
multistage heat pump (like the one in our attic for the second floor) but
does it also refer to a secondary heating source like natural gas, oil or
propane? If I had a W2 wire I suspect the 9th choice would be the most
appropriate but I just had the 4 wires mentioned above. After calling
Honeywell, the person agreed that the first choice seemed the most
appropriate.


If you have aux / emergency heat strips then it is a 2-stage heat system
(NOT a multistage heat pump, which is a different animal). Of course you
COULD have both a multistage heat pump AND aux / emergency heat, but that
is
uncommon.

4. I have heard twice now that heat pump/propane heat systems work just

fine
if you leave the temperature constant throughout the day/week, but have
trouble with "recovery" when you let it dip in the evening and try to

reheat
in the morning when everyone rises. This seems to be the problem with

these
systems and programmable thermostats. Today I programmed every day and
every "event" to the same temp to see if this pans out over the next few
days.


Ignore what you are hearing. ANY setback saves energy. Google for more
information on this widely misunderstood topic.

I AM going to get the HVAC contractor out here again, at my expense, to

pick
his brain in person, since I wasn't at home when he did the initial
inspection for us. However, any insight to the above beforehand would be

of
great help. Thanks in advance.


Good idea.





Travis Jordan January 24th 05 12:04 AM

"JohnW" wrote in message
...
I take it back. On setting 7, the heat pump comes on but nothing will
trigger the propane. Interestingly, I replaced the OLD thermostat, and the
propane comes on, but NOT the heat pump. What the hell...


What is the current outdoor temperature, and what was it when the HP was
running? Most likely you have an outdoor temperature sensor that 'locks out'
the HP when the OD temperature is below (fill in the blank) degrees..



Travis Jordan January 24th 05 12:16 AM

"JohnW" wrote in message
...

As an experiment, I put the face plate back on and pulled up the
thermostat's setup menu where the heating/cooling system is to be selected
and again browsed through the choices (note I've added details for the 7th
item in parenthesis as written in the manual):

1 heating and cooling (conventional)
2 single stage heat pump with no backup or auxilliary heat
3 heat only with no fan (conventional)
4 heat only with fan (conventional)
5 hot water heat only (conventional)
6 Cool only (conventional)
7 multistage heat pumps (heat pump with auxilliary or backup heat)
8 multistage conventional heating and cooling (2 stages heat and 2 stages
cool: requires w/w2 and y/y2 wires)
9 multistage conventional heating and cooling (2 stages of heat and 1
stage cool)
10 multistage conventional heating and cooling (1 stage heat and 2 stages of
cool)

I changed the setting from 1 to 7 and the other heat pump can on
immediately! It cycles off and on periodically as it maintains 70 degrees.
However, now the propane shut off, which always seemed to be running before.


What is the make / model of the furnace to which you have the RTH7400
connected?

Also, do you have the wires connected to the "conventional" or "heat pump"
terminals on the new thermostat?



Travis Jordan January 24th 05 12:32 AM

Travis Jordan wrote:
"JohnW" wrote in message
...
I take it back. On setting 7, the heat pump comes on but nothing
will trigger the propane. Interestingly, I replaced the OLD
thermostat, and the propane comes on, but NOT the heat pump. What
the hell...


What is the current outdoor temperature, and what was it when the HP
was running? Most likely you have an outdoor temperature sensor that
'locks out' the HP when the OD temperature is below (fill in the
blank) degrees..


It sounds like your dual fuel (HP plus propane) system is designed to run on
one or the other fuels depending on the outside temperature. That may not be
the most efficient paridigm, but it is one that is especially popular in the
northerneastern and midwestern parts of the U.S. Here in the south we run the
HP all the time (well, down to 25 degrees or so which rarely happens), and
supplement it with electric heat strips or gas if it is available.



Travis Jordan January 24th 05 04:20 PM

JohnW wrote:
The furnace appears to be made by International Comfort Products
Corporation and is the NTG3/FBF model (at least the serial number
have NTG3 as a prefix). The manuals says Installation 80+ Single
Stage.


Just as a matter of historical interest, Carrier (United Technologies) bought
ICP in 1999.

The programmable thermostat has only one set of terminals, but the
inside of the terminals are coded for conventional lettering, and the
outside are coded for heat pumps, but share the same hole for the
wi

Heat Pump Conventional
C C
G G*
Y Y*
O/B W*
RC RC
R R*

The asterisks indicate which wires I've connected. Also, the RC and
R are jumpered per instructions.

A second post has:

Conv. Heat Pump
W2 Aux
Y2 E
L
but nothing is connected there.


W2/Aux is where you'd connect the 2nd stage heat (if you had a wire for it).

I'll just see how fast I can get service in here to explain exactly
what we have, what to expect, and confirm the programmable is set up
correctly.


It sounds like you are set up OK and that the outdoor thermostat is
determining whether the HP or propane funance is used when the thermostat
calls for heat. How is the system working today?



JohnW January 24th 05 10:44 PM

I put the old thermostat back on, and it's working fine--the house is cozy.
Still no heat pump, but the propane seems to be doing it's thing now. Don't
get it--the night/day temps are the same. Something's just not right with
the programmable thermostat. I have a service tech coming out (again) on
Wednesday, and I'll pick his brain. Thanks for all your input--it's been an
education!

John

"Travis Jordan" wrote in message
...
JohnW wrote:
The furnace appears to be made by International Comfort Products
Corporation and is the NTG3/FBF model (at least the serial number
have NTG3 as a prefix). The manuals says Installation 80+ Single
Stage.


Just as a matter of historical interest, Carrier (United Technologies)
bought
ICP in 1999.

The programmable thermostat has only one set of terminals, but the
inside of the terminals are coded for conventional lettering, and the
outside are coded for heat pumps, but share the same hole for the
wi

Heat Pump Conventional
C C
G G*
Y Y*
O/B W*
RC RC
R R*

The asterisks indicate which wires I've connected. Also, the RC and
R are jumpered per instructions.

A second post has:

Conv. Heat Pump
W2 Aux
Y2 E
L
but nothing is connected there.


W2/Aux is where you'd connect the 2nd stage heat (if you had a wire for
it).

I'll just see how fast I can get service in here to explain exactly
what we have, what to expect, and confirm the programmable is set up
correctly.


It sounds like you are set up OK and that the outdoor thermostat is
determining whether the HP or propane funance is used when the thermostat
calls for heat. How is the system working today?





Travis Jordan January 25th 05 12:03 AM

JohnW wrote:
I put the old thermostat back on, and it's working fine--the house is
cozy. Still no heat pump, but the propane seems to be doing it's
thing now. Don't get it--the night/day temps are the same.
Something's just not right with the programmable thermostat. I have
a service tech coming out (again) on Wednesday, and I'll pick his
brain. Thanks for all your input--it's been an education!


You are welcome. Unless you've miswired something (and I don't think you
have) my supposition is that something is going on with the ODT (outdoor
thermostat) control on your HP condenser.

Let us know what the service tech finds?



JohnW January 28th 05 03:47 AM

Travis:

After all this, here's what happened:

The service tech arrived and I discussed all the issues. Several
significant factors:

1. My assertion that one of the outside units was an air conditioner was
correct! Our main floor/basement has propane heat and that's it! When I
explained that his colleague got it all wrong, he told me I misunderstood.
Yet the service ticket from two week's earlier had clearly written
references to the "first" and "second" heat pump. Oh.

2. He spent a lot of time in the room with the furnace, fiddling here and
there. Sometime later he indicated he could find nothing wrong. However,
we have had several more days with sub-15 degree evenings, and the house is
heating like a sauna. It's 12 degrees outside and the house is sitting at
72 with no problems. Something "changed". $108 dollars worth of labor, but
at least we're warm.

3. I had wired the programmable thermostat correctly. I suppose having only
4 wires is pretty much idiot proof, although I'm sure you industry folks
have seen it all.

I wish I knew what was adjusted for you all, but frankly I'm just happy the
system is working at this point. It's isn't getting all that much warmer
soon!

Thanks again.

John


"Travis Jordan" wrote in message
...
JohnW wrote:
I put the old thermostat back on, and it's working fine--the house is
cozy. Still no heat pump, but the propane seems to be doing it's
thing now. Don't get it--the night/day temps are the same.
Something's just not right with the programmable thermostat. I have
a service tech coming out (again) on Wednesday, and I'll pick his
brain. Thanks for all your input--it's been an education!


You are welcome. Unless you've miswired something (and I don't think you
have) my supposition is that something is going on with the ODT (outdoor
thermostat) control on your HP condenser.

Let us know what the service tech finds?





Travis Jordan January 28th 05 02:50 PM

JohnW wrote:
I wish I knew what was adjusted for you all, but frankly I'm just
happy the system is working at this point. It's isn't getting all
that much warmer soon!


Thanks for the follow up, John. Glad to hear that everything is working
for you now.




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