Furnace aux heat running a lot.

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oilstinks

Minister of Fire
Jan 25, 2008
536
western NC
Had a new carrier furnace heat pump system installed for this season. This was a completely new install. The furnace is propane backup. First heat pump system I've had so it's all new to me. The problem is the aux/propane side runs a lot. Out side temp was 46deg and aux was running. Ad I type this its 37 out and it is running. I know around 35 that heat exchange does not work well. Does this sound right. The furnace guys are about an hour away. Just thought I'd ask here in case it was something simple. Thanks
 

Dataman

Minister of Fire
Sep 10, 2018
1,012
Newport, Wa
Thermostat Model? I know when I installed mine I got setting wrong and it functioned like yours does. Check your settings against the manual. Here is my Manual. You need to find your's for make and model.
 

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oilstinks

Minister of Fire
Jan 25, 2008
536
western NC
16064829811608390108790575049062.jpg
16064829811608390108790575049062.jpg
 

oilstinks

Minister of Fire
Jan 25, 2008
536
western NC
16064832014862050976715261291624.jpg
 

oilstinks

Minister of Fire
Jan 25, 2008
536
western NC
My upstairs unit which is not propane aux but electrical has run the outside compressor as low as 28 degrees. Odd.
 

oilstinks

Minister of Fire
Jan 25, 2008
536
western NC
Balance point was set at 40 after much internet searching. I set it it at 35 and after one heatpump cycle the propane aux ran again. The indoor twm dropped 1 deg rapidly at this point. Don't know at this point. Compressors are on the southside but are blocked much of the day by large white pines.
 

oilstinks

Minister of Fire
Jan 25, 2008
536
western NC
No but the thermometer for the system to know the outdoor temp is there.
 

fbelec

Minister of Fire
Nov 23, 2005
3,107
Massachusetts
it's definitely in the thermostat. those honeywell thermostats you have are way to complicated. there are so many settings in it. there should be a setting for how long the heatpump runs before changing to 2nd fuel. i don't like to put those in because of the problems. beware if you call tech support you might not get any where they are just computer readers. (useless)
 

fbelec

Minister of Fire
Nov 23, 2005
3,107
Massachusetts
and hopefully it's not in the board out at the heatpump. it can be that for it doesn't know the right temp outside.
 

semipro

Minister of Fire
Jan 12, 2009
4,077
SW Virginia
On some thermostats, a difference of X degrees or more between actual and set temps will engage the aux heat. X is usually about 2F. On newer thermostats you may be able to change the value of X or do some other programming to determine when aux heat comes on.

Any newer, self-respecting air-air heat pump should be able to provide heat down to about 32F or below, regardless of shading. It sounds like something is set up wrong and I agree with the others that think it's the thermostat.
 

MTY

Feeling the Heat
Jan 9, 2019
495
Idaho
This was a new one on me too. My HP will call for heat from the strips if there is a 2-3 degree temp difference between the house temp and the thermostat setting. After initial heat up, the aux heat drops out. I thought it was broken, but I was wrong.
 

fbelec

Minister of Fire
Nov 23, 2005
3,107
Massachusetts
with that thermostat you should be able to adjust that 2 degrees to 5 if i'm not mistaken and with any heating system you should never set back more than 5 degrees or the savings goes out the door
 

oilstinks

Minister of Fire
Jan 25, 2008
536
western NC
Temps never change more than 1 deg inside so I know its not that. Upstairs unit is heat strip back up and the HP runs a whole lot. Was 17 deg out this morning and other unit was running.
 
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Dataman

Minister of Fire
Sep 10, 2018
1,012
Newport, Wa
The OP needs to talk to the Manuf of Therm. They have 800 number. I had same problem and fixed it by settings. Or hire Professional.
 

MTY

Feeling the Heat
Jan 9, 2019
495
Idaho
I'm guessing this was a reply to me. So here here goes. I am gone for 3 days per week. As long as the temps do not get into the low 20's the inside temp stays about 52-53. I set the thermostat at 50 before I leave, and the heat does not run for 3 days, that is from Wednesday afternoon until Sunday mid morning. My November electric bill was $66 and change. Are you saying it would be lower if I let the heat run at say 68 for the three days? I know the monthly bill will rise as I spend more time there, run the washer and dryer more, and use more hot water. I'm still expecting it to be easy on utility costs.

with that thermostat you should be able to adjust that 2 degrees to 5 if i'm not mistaken and with any heating system you should never set back more than 5 degrees or the savings goes out the door
The other night while bored I ran the heat up to 70, turned it way down and watched the inside temp. I did not have an outside thermometer, but it was just beginning to freeze. I lost one degree inside in 46 minutes. I assume as the inside and outside temps begin to approach one another the time to lose a degree of inside heat would increase.
 

fbelec

Minister of Fire
Nov 23, 2005
3,107
Massachusetts
i had know idea you were gone that long. but 66 dollars wow. when you do get home running from 50 to 70 should kick on the emergency heat (electric). the heat pump up stairs unless it's a ductless split should not be running at 17 degrees. if it's a regular ducted system it should kick over to the other fuel (electric) at 32 degrees. as useless as they are i would call tech support for those thermostats. that thermostat if wifi also should tell you your outside temp.
 

oilstinks

Minister of Fire
Jan 25, 2008
536
western NC
I
i had know idea you were gone that long. but 66 dollars wow. when you do get home running from 50 to 70 should kick on the emergency heat (electric). the heat pump up stairs unless it's a ductless split should not be running at 17 degrees. if it's a regular ducted system it should kick over to the other fuel (electric) at 32 degrees. as useless as they are i would call tech support for those thermostats. that thermostat if wifi also should tell you your outside temp.
Think you are confusing posts. My bill was not 66. Upstairs is a 1.5ton HP with electric back up. Believe it or not the upstairs is always colder than main floor by about 3deg and that tstat is in the open loft.
 

fbelec

Minister of Fire
Nov 23, 2005
3,107
Massachusetts
i just crammed to much info in a sentance. that is also strange to have it cooler upstairs than downstairs.
 

oilstinks

Minister of Fire
Jan 25, 2008
536
western NC
Well I had enough and called the installer and he said he would send me an Ecobee at no charge. Good choice or should I bite the bullet and just buy something else?
 

fbelec

Minister of Fire
Nov 23, 2005
3,107
Massachusetts
just reread the whole tread i think that thermostat has a spot for a outside temp sensor if not it should be using the internet for the closest stations temp.

the ecobee is a nice thermostat it's now just as easy to hook up as the nest. something is telling me that the compressor pc board needs to be changed. heat pump should only run down to 32 degrees. if it runs at a lower temp it will jack up your electric bills.

when the thermostat calls for heat it sends power from the red wire to the white. on a heat pump that white runs to the heat pump. if the temperature outside at the heat pump drops below 32 the heat pump sends the signal from the thermostat to the indoor unit (other fuel ) to run. thats how the heat should be running. if it is a 2 stage compressor there should be y1 and y2 for the stages. the stages can be controlled by the thermostat. usually 10 to 15 minutes it will go from starting on low to high including the air handler/furnace.
 

oilstinks

Minister of Fire
Jan 25, 2008
536
western NC
The heat pump runs as should except for a 2-3 deg window above set point in thermostat i.e. if 40 then 40-42 or 43. That's when it cycles for just a few seconds. Everything else works as it should with no problems; Propane aux, and AC. I have no idea if it's a 2 stage or not.
 

EbS-P

Minister of Fire
Jan 19, 2019
1,457
SE North Carolina
heat pump should only run down to 32 degrees
COP 17.( That’s coefficient of performance which says how much energy you get out divided by how much new you use at 17 degrees F). For most new heatpump pumps that should be around 2.

So you have to do the math with price of propane to see if 32 degrees is really the cut out temp you need.

Really setting up the thermostats is not all that complicated, but it needs to be done correctly and not just getting the correct wires to the correct terminals but also the internal settings of the thermostat. It matters if you have a two stage compressor (if you do you really have 3 heating stages and two cooling). I have two stage and electric backup and to be honest I have read the manual 3 times and I’m not really sure I could get it all hooked up correctly (the emergency vs auxiliary heat is a bit confusing).

My HVAC tech hates Nest products. Gets a couple calls a week just because of the thermostat.

Just my thoughts
Evan
 

fbelec

Minister of Fire
Nov 23, 2005
3,107
Massachusetts
i have not seen or heard of the heat pump that is the conventional way with a conventional outside compressor and ductwork have a low temp run. the ductless splits are the only ones that i've heard and seen go down to minus 15 f.::F. all of the thermostats that i work with are either emergency heat or aux heat to the tstat it's the same. the only issue that i've run into with the nest is when they say (nest) they can be run without a common wire they work for about a year then stop working until there is a common added in. just did 3 of them. the ecobee is what the hvac guy is installing now. (me for him ) it needs a common but has separate sensors you can put in other rooms that are on the same zone and maybe a little cooler, the thermostat figures out what to run extra time to level the temps in those rooms
 
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