Heat pumps: something to ponder

[The Original Rooster]

68 may be 68 when the unit is off and the house up to temp but when it's running, and actively moving air through the house, 120 degree gas furnace air is definitely warmer than 85 degree heat pump air.

When my heat pump kicks on, it feels like a cold draft. When my old gas furnace kicked on, it felt nice and toasty.

Then you're one of the folks who like to back up to a warm vent. Yep, a heat pump won't feel as hot as a gas furnace. The problem I have with gas heat isn't the warmth, it's how dry it makes the air. Wears my sinuses out!

 

[Dustin Pate]

I've got two heat pumps at the house and I couldn't be happier. My power bills are very reasonable.

 

[Milkman]

is it common for the outside unit to freeze over during below freezing temps like now?

If the system is operating properly it will go into defrost mode periodically.
Basically it switches to ac mode for a short period.
That melts away any frost trying to build up on the coils.

 

[Oldstick]

Responding to the OP, yes the system does monitor the ambient temps as far as the heat strips are concerned. But it is the inside thermostat that is monitored, not the outside.

Most systems, if the inside temp drops more than 2 or so degrees below your thermostat setting, the heat strips come on to supplement the heat pump system. That normally only happens during the temporary cold spells we get down south.

Move the exact same house up to North Dakota at minus 20 and you might as well junk the heat pump in the winter.

 

[Beagler]

My auxiliary heat comes on when the outside gets about 27 degrees. It also had emergency heat that I can manually turn on. But with it getting as cold as it’s supposed to be this weekend, I’ll be firing my wood heater up in that morning.

 

[Oldstick]

Most systems will kick on the strips when it’s 32 outside and the system has failed to raise the temp inside in a certain time frame.
The process of exchanging heat quits working depending on cold, humidity etc.
The system won’t know it’s 32 outside, just that it is not changing the temp inside anymore.

Exactly correct. No matter if it is 40 outside or -40. If the heat pump alone isn't able to keep the inside temp up to what the thermostat setting is, the strips will come on and try to help. The strips are either ON or OFF. No such thing as low, medium or high.

You want them to stay OFF as much as possible to avoid higher electric bills. That's why they recommend you choose one comfortable setting for the thermostat and leave it there.

Now the strips ARE going to be coming ON for us in GA in the next week or two, due to the predicted cold. Nothing we can do to change that. But if it becomes a long term problem, then something could be wrong with your AC system or the house needs added insulation, etc.

 

[Baroque Brass]

We also have unvented gas logs. I’ll set them to cycle to supplement the heat pump until we get through this cold snap.

 

[Baroque Brass]

We have a heat pump. Best thing we did when building the house was the spray in insulation. Exterior walls and under roof. Like an igloo. Our temp doesn't never change from what we have it set on (summer or winter) and the unit hardly runs.

Now the next 4 days will be the true test......

We did spray foam in the attic, wish we’d done the walls too. Having the attic done makes a huge difference in the summer. The attic stays out the same temperature as the conditioned space.

 

[jaybirdius]

Proper design is the key to any HVAC system. Our house is heat pump with a heatilator wood stove for back up. We haven't needed the woodstove in the past 3 years. Return and vent placement is critical to eliminating the drafty feeling. My HVAC guy did an amazing job with the design and placement of my system.