This is my first winter in this home, just moved in this past July. So I get my electric bill and it's been running more than usual every since I moved in here. It wasn't too much more so I just paid it and brushed it off. Well this past month it was $456!! I've never had a bill higher than $125! I had noticed something just didn't seem "right" with heat pump/furnace/thermostat, one or a combo of the three. The wall thermostat displays room temp and the set temp. So when I turn heat up the room temp # goes down (gets colder) and because of this my furnace constantly runs because room temp never goes up to set temp. When I turn set temp down to kick heat off the room temp # goes up (gets warmer). So does anyone know, does this sound like I need a new thermostat?enter image description hereenter image description hereenter image description hereenter image description hereenter image description here

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    – BMitch
    Jan 8 '17 at 15:23

Revised answer

OP appears to have a separate standalone electric furnace and a separate standalone air conditioner controlled by one common thermostat and possibly connected ductwork.

OP states that, despite the home being reasonably warm, the thermostat reads a cold temperature and the displayed reading drops when the furnace is on.

OP states that the electric bill is very high.

Recommendations to get by:

  1. The thermostat may be affected by cold air being sucked through the wall from outdoors. Stuff insulation in the wall behind the thermostat. If that does not work, then a new thermostat may be needed.
  2. Turn off the outdoor service disconnect to the outdoor A/C unit. It should not be running during the winter no matter what.
  3. Limit the warm air loss that is occurring through the ducts to the A/C unit outside. If it has separate ducts from the furnace, cover the registers that go to the outdoor A/C. If it shares the same ductwork then you might need to make some sheet metal dampers and install them.

Electric heat costs the same whether from an electric furnace or a portable space heater, but space heaters can be used to heat a small area compared to an electric furnace. Since the bill is so high, the furnace duct work may be responsible for losing heat to outdoors. OP may be better off switching to electric space heaters for now if not up to inspecting and making revisions to the duct work. Just be careful to respect that portable electric heaters do pose a slight fire risk.

Alternatively, OP could switch to a portable propane heater rated for indoor use. Something like this:

enter image description here


At today’s energy prices in OP's situation, heating with propane should save money compared to heating directly with electricity. If you go this route, only use a unit specifically designed for indoor residential use.

End of revised answer

Prior answer

OP's updated information shows he does not have a heat pump. The information below is still applicable to heat pump owners.

Yes, if you have a heat pump then you do need a different model of thermostat and that might not be your only problem.

First, are you certain you have a heat pump and not just an air conditioner with an electric furnace?? I cannot see any thermostat connections to either the “O” or “B” terminals. Either this system is mis-wired, or you have a simple air conditioner and not a heat pump. Check the model number on the condenser outside to verify that it is a heat pump, or look through the top grill of the condenser for a reversing valve that looks like this:

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If you don’t have one of these in the outdoor unit then you have a simple air conditioner.

Assuming it is a heat pump, then you have a system with 15.4 KW electric backup heat. The White-Rogers 1F78 is intended for a heat pump system without backup heat and according to the installation guide it lacks the circuitry to correctly control the backup.

An easy way to get eye-popping electric bills is to fire the electric backup heat and simultaneously activate the heat pump in air conditioning mode. Depending on the condition of your system, that combination might even cool the house a little while the meter spins like a gyroscope.

For starters:

  1. Disconnect the yellow wire from your thermostat – do that now.

  2. Disconnect the white wire from the “Y” terminal and connect it to the “W” terminal.

  3. Verify that the concealed sliding switch below the white sliders at the lower right quadrant of the thermostat is in position corresponding to “ELEC” (left).

These changes will disable your heat pump and leave the thermostat controlling the electric heat only, assuming the electric heat works without issue and assuming that the white wire is connected to the control relay for the electric heat, which is the standard convention. Judging from the condition of the unit, my assumptions here may not be true for your system. If these changes get you some warm air out of the registers when the existing thermostat calls for heat, then:

  1. Identify the wire at the thermostat which connects to the reversing valve. By convention, that should be the orange wire.

  2. Get a proper heat pump thermostat that can handle electric backup heat. Here is a reasonable basic model: http://www.homedepot.com/p/Honeywell-5-2-Day-Programmable-Thermostat-with-Backlight-RTH6350D/202216464

  3. Wire up the new thermostat according to the directions. From your top photo it looks like you might have split power supplies on your system, so pay special attention to the Rh and Rc connections.

You will need to physically verify which wires run where. The standard convention is: R/Rh – 24vac furnace, G- Fan, Y – compressor, O – reversing valve, W/AUX – electric heat. In your thermostat photo the brown wire appears to connect to Rc, which would mean your outdoor unit has its own 24vac transformer and brown is connected to the transformer outside. That’s fairly unusual so you will need to verify that. Describe what's there if you find something different.

If nothing else is actually broken, then those changes should get you going.

End of prior answer


Because we had two warm winters in a row, followed by a really cold one.

All but the newest heat pumps can't pump heat if it's too cold. (they might be able to, but they'd be so inefficient you'd be spending more than 1 watt of pumping effort to move 1 watt of heat, and that's silly). In that case, the heat pump shuts off entirely, and it heats your home with resistive electric heaters built into the air handler. This is rather expensive, and the concept is this doesn't happen very often (the heat pump is cheaper the rest of the year, as compared to good old gas heating and air conditioning). They didn't foresee this winter. They also didn't foresee fracking, which is holding gas prices low.

Read the manual for your unit, and look at (or just remember) weather data in your area. I bet you're seeing a lot of times where the pump can't run.

By the way, you can see it right on the heat pump data. The heat pump wants a 30A and a 60A breaker. Look at the outdoor unit, where all the heat-pumping occurs, that's a 23.9A motor (sized just right for the 80% derate for continuous use of a 30A circuit). So your heat pump is 30A. The 60A is for the backup resistive heaters. So twice as much, plus probably running more often due to the extreme cold.

That said, if your thermostat is acting eccentric, replace it just to be sure.


A heat pump is an air conditioner that has a reversing valve that reverses the refrigerant flow to the coils, this makes the indoor coil hot in the heat mode,it rejects heat indoors in the heat mode and is air conditioning the world when it uses the outdoor "heat" to "boil" (change state) of the refrigerant from a liquid to a vapor.

The coil in the AC mode is around 40F degrees, much colder and it will freeze the coil up.

This is why a heat pump dramatically loses efficiency (ability to heat) at 40F outdoor temperature and below.

The liquid refrigerant cannot change state (boil) if the air outdoors is at the same temperature or lower than the refrigerant, in fact it will sub cool the refrigerant thats opposite of boiling it, a compressor cannot accept liquid refrigerant, it hydraulics the motor which locks it up if you are lucky or if not lucky blows the valve plate, blows a rod. At 40F the compressor is losing or has lost its ability to pump heat, you can easily tell when by testing the larger the temperature of the lineset temperature, the 2 copper pipes connected to the outdoor unit, the larger one will be hotter, be careful, it may be too hot to touch by hand for long, if it is still hot it is doing work, at 35F or less it is best to use electric heat.

Electric resistive heat is 100% efficient at converting 1 Watt of power to BTU's

A heat pump which utilizes the refrigeration cycle is up to 300% efficient at converting 1 Watt of power to BTU's.

So if a home had electric strip heat and a $450 a month power bill, switching to a heat pump will cost about $150 to provide the same BTU's as the old heater.

You can see why resistive heat is very rare these days, it is very expensive.

If I had an electric furnace with ductwork I would not use that to heat ever, I would get several space heaters, none above 1200 Watts each, preferably adjustable in heat modes, I have one that is as low as 500 Watts in low heat, the 1500 watt heaters stress a homes 20 amp circuits in my opinion so I only run my heaters at 900 Watts or below, it is much cheaper to heat a room or 2 rooms than a home.

The biggest reason not to use the big heater is infiltration of cold outdoor air into your home. There is no 100% sealed system meaning there are leaks, if you are leaking air in the attic the furnace is not sending all the air it removed back to the house it sends it into the attic, that means the air that leaks is replaced by outdoor air via a chimney flue or dryer vent or stove vent, bathroom vent, cracked window or light switches and outlets.

I had a person tell me their fireplace would smoke out the house if the AC was ran, I wondered why the fireplace would be going with the AC on but checked it out and the furnace had an entire duct come loose in the attic losong about 15% of the air to the attic meaning that much air from outdoors was entering the home and the fireplace is an easy way to get air into a home.

Space heaters use no duct work and cannot lose heat to the attic, 100% of the heat goes indoors that means 100% of every dollar you spend heating goes to heating the house not the world.

  • 1
    Hello again. There's a lot of great info here, and it looks like you spent some time on it, but it doesn't really answer the question. A shorter, more focused answer would have been better. Mar 4 '19 at 12:30
  • Also, I went ahead and edited your post to include paragraph separation as you intended. You need to hit return twice to make a pragraph mark appear, otherwise it runs it all into 1 paragraph. You can edit your own answers using the edit button found directly under your answer. It's not a button, it's a word. Mar 4 '19 at 14:59
  • Please take the time to re-read your answers after you post them, to assure they match your intent. If not, just edit, this is normal here. If you see someone else doing formatting in a way you like, hit edit on their answer and see how they did it. Just don't save the edit. Mar 4 '19 at 15:01

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