Unnecessary Emergency Heat!!

SG_Player1974

New Member
I recently read a post on another thread that said if someone was to manually increase their heating by 2 or more degrees that it would automatically default to the Emergency heat. I tried this with my unit and it was completely true! I passed this little nugget along to others who have also found it to be true with their systems as well. My system is a 16 SEER Trane.

So... now I would like to know some other info regarding this:

1) Does this happen also when the thermostat is PROGRAMMED and the adjustment is more than 2 degrees? Basically... is my EH kicking on EVERY time my heat comes on and the temp is 2 degrees difference?
2) Is there a way to have it NOT go on EH when manually adjusting and the temp difference is 2+ degrees? Seems ridiculous to me that you do not have a choice. If my house is 67 and I want to go to 70... why should I be FORCED to use the EH?
 

MMDad

Lem Putt
I recently read a post on another thread that said if someone was to manually increase their heating by 2 or more degrees that it would automatically default to the Emergency heat. I tried this with my unit and it was completely true! I passed this little nugget along to others who have also found it to be true with their systems as well. My system is a 16 SEER Trane.

So... now I would like to know some other info regarding this:

1) Does this happen also when the thermostat is PROGRAMMED and the adjustment is more than 2 degrees? Basically... is my EH kicking on EVERY time my heat comes on and the temp is 2 degrees difference?
2) Is there a way to have it NOT go on EH when manually adjusting and the temp difference is 2+ degrees? Seems ridiculous to me that you do not have a choice. If my house is 67 and I want to go to 70... why should I be FORCED to use the EH?

If you use a programmable thermostat it uses a "heat recovery" mode. It slowly warms the house so it reaches the desired temperature when you want it. It avoids using the aux heat. The only way to avoid the aux heat is to turn up the heat slowly in 1 degree increments. Even then, if it's cold enough outside it will use some aux heat.
 

SG_Player1974

New Member
If you use a programmable thermostat it uses a "heat recovery" mode. It slowly warms the house so it reaches the desired temperature when you want it. It avoids using the aux heat. The only way to avoid the aux heat is to turn up the heat slowly in 1 degree increments. Even then, if it's cold enough outside it will use some aux heat.

I have yet to experience the "heat recovery" mode. Every time I increase the temp by 2+ degrees.... ON comes the EH! :faint:
 

itsbob

I bowl overhand
If you use a programmable thermostat it uses a "heat recovery" mode. It slowly warms the house so it reaches the desired temperature when you want it. It avoids using the aux heat. The only way to avoid the aux heat is to turn up the heat slowly in 1 degree increments. Even then, if it's cold enough outside it will use some aux heat.

TRUEBUT!!

Putting Your Heat Pump on a Programmable Thermostat
Most garden-variety heating system programmable thermostats are just timers like an alarm clock. You set it at 65ºF from 10 PM until 5:30 AM. When the morning alarm goes off at 5:30, it just jacks the setting up to wherever you've set it to go—say 72ºF—and the furnace cycles on, and, by the time your feet hit the floor at 6:30, the house is toasty warm.

You can—as many people have done—place an ordinary programmable thermostat on your heat pump system. However, while the perception of savings with the operation of lowered night heat with a morning warm-up will be there, it often actually costs you more in energy usage than if you'd left the heat pump set at the daytime temperature all night long! This is because when the signal from the thermostat comes to start things up, the thermostat thinks it's linked to a gas or oil furnace and goes right to the higher setting. This causes the auxiliary heat to come on, and stay on, until the desired temperature is achieved.

Make Sure You Buy the Right Thermostat
The key to buying the right programmable thermostat is finding the words "heat pump" in the product’s name. It must be specifically designed to elevate the temperature setting—and to wait for it to achieve it—1ºF at a time. That means if you've turned the setting at bedtime to 65ºF, the heat pump programmable thermostat has to figure out how many hours ahead of time it has to start working on raising the temperature to get it to the morning setting.

It has to be this specific type of thermostat to do you any good. Several manufacturers make heat pump specific programmable thermostats; but, you have to be sure they’re compatible with your system. Read the directions carefully and double check your installation before making the decision to purchase a thermostat.
 

itsbob

I bowl overhand
I have yet to experience the "heat recovery" mode. Every time I increase the temp by 2+ degrees.... ON comes the EH! :faint:

Last year I bought programmable thermostats for upstairs and downstairs.. this year I'm setting my heat pump to 72 and leaving it alone.

I think looking back that I cost myself a LOT of money playing with the programmable thermostat, and I'm POSITIVE I didn't buy the "heat pump specific" or one that was compatible with my heat pump..
 

Gilligan

#*! boat!
PREMO Member
I have yet to experience the "heat recovery" mode. Every time I increase the temp by 2+ degrees.... ON comes the EH! :faint:

That is either simply because it is your finger manually creating the "step" change in commanded temperature that triggers the aux heat (that action overrides the programmed temperature v time profile) ..or your thermostat does not support/include a "heat recovery mode" of operation. Do you have the operators guide for your thermostat?
 

SG_Player1974

New Member
That is either simply because it is your finger manually creating the "step" change in commanded temperature that triggers the aux heat (that action overrides the programmed temperature v time profile) ..or your thermostat does not support/include a "heat recovery mode" of operation. Do you have the operators guide for your thermostat?

I do still have the guide. I guess that would be a good place to look huh?

Going into what Bob said.... I do have my thermostat programmed for different times of the day. I do believe that even when I have it PROGRAMMED and the difference between temp changes is 2+ degrees.... the EH will kick on. So basically, it will do it whether it is programmed -OR- manually changed.

This was all part of the system that was installed by Besche (now SMO)

I'm gonna experiment with the programming tonight to see if the EH always comes on when the temp changes.
 

MMDad

Lem Putt
I do still have the guide. I guess that would be a good place to look huh?

Going into what Bob said.... I do have my thermostat programmed for different times of the day. I do believe that even when I have it PROGRAMMED and the difference between temp changes is 2+ degrees.... the EH will kick on. So basically, it will do it whether it is programmed -OR- manually changed.

This was all part of the system that was installed by Besche (now SMO)

I'm gonna experiment with the programming tonight to see if the EH always comes on when the temp changes.

I REALLY hate to say this, but Bob is right. Make sure your thermostat is heat pump compatible. If not it's wasting a lot of money.

My old system with a standard thermostat gave me electric bills up to $300/month. With a new efficient system and a programmable thermostat, November was < $150. That's for an all electric house with three people. Of course, getting rid of my wife has helped immensely but that is not an option for everyone.
 

Gilligan

#*! boat!
PREMO Member
I do still have the guide. I guess that would be a good place to look huh?

Going into what Bob said.... I do have my thermostat programmed for different times of the day. I do believe that even when I have it PROGRAMMED and the difference between temp changes is 2+ degrees.... the EH will kick on. So basically, it will do it whether it is programmed -OR- manually changed.

This was all part of the system that was installed by Besche (now SMO)

I'm gonna experiment with the programming tonight to see if the EH always comes on when the temp changes.

I know the previous programmable stat we had in our office was just a "dumb" device that would kick on the aux heat for any step change in set value that was more than the 2 or 3 degree difference. The one we have now was put in when the new heat pump and air handler were installed a year ago and now the aux heat almost never kicks on.
 
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imaref

Active Member
I have the CoolSentry thermostat from SMECO. I figured out how to get around the EH coming on (unless it's really, really cold outside). I keep the temp at 67 during the day. At 11PM it is set at 64 degrees (my house is 3 floors so it's still nice and warm upstairs during the night). I set the "morning" program at 66 degrees (EH doesn't come on because it's only 2 degrees difference), and then an hour later I set the "day" program at 67 (EH doesn't come on since it's only 1 more degree).

I had called SMECO back in the fall because I used to have it set for 64 at night and then 67 in the morning and the EH was coming on every day. After talking to an engineer at SMECO, he suggested doing it more gradually as described above.
 

Blister

Active Member
Heat pumps have been around since when, the late 70's, early 80's. I am amazed that this was not common knowledge. Any energy use information source since their introduction that I ever read always suggested not changing the t-stat setting at less than an 8-12 hour interval. Changing it more often(more than 2-3 degrees) will always be less efficient than leaving it alone. Especially with electric resistance "toaster" elements, not so bad with gas/oil backup.
 

Midnightrider

Well-Known Member
Isnt it possible that using the EH for a short period to get the house up to temp is MORE efficient than using the heatpump for a much longer time?
I dont know, i am just asking, but it seems there would be a break even point and it just might be 2 degrees.......
 

Gilligan

#*! boat!
PREMO Member
Generally speaking, a typical electric heating element in a heat pump air handler burns twice as much electrical power as the heat pump does when operating normally.
 

SG_Player1974

New Member
Isnt it possible that using the EH for a short period to get the house up to temp is MORE efficient than using the heatpump for a much longer time?
I dont know, i am just asking, but it seems there would be a break even point and it just might be 2 degrees.......

I don't know about this BUT.... I can say that since I implemented this little nugget of knowledge... my electric bill has been down $75-100 per month compared to the year before. :yahoo:

Of course, according to SMECO... I am still using WAYYYYYYY more than my neighbors! :coffee:
 

Blister

Active Member
Isnt it possible that using the EH for a short period to get the house up to temp is MORE efficient than using the heatpump for a much longer time?
I dont know, i am just asking, but it seems there would be a break even point and it just might be 2 degrees.......

Exactly. The break even point is what they are designed for. At more than 2 degrees it is more economical to use the EH for rapid temp. rise. That is why t-stats are made that way. At less than 2 degrees the heat pump can raise room temp. more efficiently. If you lower your house setting to 62, leave the house to work for a 10 hour day, then raise it 70, the heat pump might run for an hour or more to reach 70. Then you have to consider "thermal mass". After the air temp. reaches 70, your sheet rock walls, floors, furniture, and all other items in your home have a mass that must be raised to 70 or they will cool the air, and require the heat pump to cycle on again.
 

Goldenhawk

Well-Known Member
When you're looking in the manual, specifically check out the Installer Instructions (or something similar). Usually the aux heat threshold or split is programmable in 1-deg increments, and the Recovery Mode feature is also optional. Those could be factory-preset at 2 deg and OFF, unless the installer changed them manually. You want Recovery Mode ON, not off, so it slowly ramps the temperature up starting early.

If not, go buy a new programmable thermostat from Lowes for $60 or so, or even $40 for a cheap one. It will pay for itself inside of a year, and they're really not that hard to install.
 

Gilligan

#*! boat!
PREMO Member
Exactly. The break even point is what they are designed for. At more than 2 degrees it is more economical to use the EH for rapid temp. rise. .

I can certainly understand how using the combined BTUs of the EH and heat pump together would increase the room temperature more rapidly than the heat pump alone, but I'm not sure I follow how using more than twice the power for, lets just say, half the amount of time, is less total power consumed.

That said..the heat rate is certainly affected a great deal by outside temp...and I've watched ours struggle mightily for a long time to bring the temp up when its really cold out...below 30 or so.
 
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