Heat Pump wiring 5 wires on thermostat 4 wires on heat pump
#1
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Heat Pump wiring 5 wires on thermostat 4 wires on heat pump
What would be the best way to wire a heat pump? I have 5 wires for thermostat 4 wires to heat pump. I have a Ecobee 4 to 5 wire power extender that is suppose to be able to uses on heat pump to work as 5 wires. It would be next to impossible to change wiring.
Thanks for any help
Thanks for any help
#2
Welcome to the forums.
We cannot guess. You'll need to post a picture of the wiring on the existing thermostat
and tell us the model number of that stat.
How-to-insert-pictures.
We cannot guess. You'll need to post a picture of the wiring on the existing thermostat
and tell us the model number of that stat.
How-to-insert-pictures.
#4
No need to start a new thread. If you don't get a reply..... just bump this thread.
I've been unable to reply for the last three hours. Just got back on.
As I mentioned..... I need to see a picture of your wiring. If you can't take and post a picture.... pull the stat off the base and tell me what color wire is on which terminal.
I've been unable to reply for the last three hours. Just got back on.
As I mentioned..... I need to see a picture of your wiring. If you can't take and post a picture.... pull the stat off the base and tell me what color wire is on which terminal.
#6
To run a basic heat pump system you need.....
1) R - 24v power
2) Y - compressor
3) W/aux - back up electric heat
4) G - blower control
5) O/B - reversing valve control
That would be a minimum of five wires.
If you're installing a wifi stat you need a C wire which makes six wires needed.
1) R - 24v power
2) Y - compressor
3) W/aux - back up electric heat
4) G - blower control
5) O/B - reversing valve control
That would be a minimum of five wires.
If you're installing a wifi stat you need a C wire which makes six wires needed.
#8
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You would need 5-6 wires. A power extender will not help in your case. It’s for consumers with no common. That is not your problem.
How did this unit run in the past with only a 4 conductor bundle?
The use of electric heat is mandatory if you live in a cold climate. For normal unit operation.
How did this unit run in the past with only a 4 conductor bundle?
The use of electric heat is mandatory if you live in a cold climate. For normal unit operation.
#10
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You’d eliminate the cooling function in the unit then.
How did this unit run previously with only 4 conductors? How is it wired now? Post photos of the wiring.
How did this unit run previously with only 4 conductors? How is it wired now? Post photos of the wiring.
#14
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Anytime your running electric heat, your elevating your electric bill tremendously. An efficient heat pump keeps electric heat off as much as possible.
If this is a new unit, does the installer have any suggestions?
If this is a new unit, does the installer have any suggestions?
#17
Yes you could manually control the heat strips but you need to remember that the heat pump condenser needs to to defrost. It needs to bring the heat coils on un-attended.
#18
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The handler is upstairs and there is no way to get to wiring with out cutting through several walls. Then I would have to have it run down the outside of wall from second floor. ugly
Is there any other way?
Is there any other way?
#20
If you didn't already have the equipment you could opt for communicating equipment.
It communicates on several wires.
It communicates on several wires.
#22
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OK I been thinking I ony have 4 wires going to hp. You need 2 wires for comp and 2 wires for dev valve to heat. Why can't I jump from comp one side to dev valve. Of course I need to make sure I on opposite of trans for the wire going to dev valve? That would free up 1 wire I need.
#23
You need....
1) R - 24v power
2) C - common
3) Y - compressor
4) O/B - reversing valve.
So technically four wires will run your condenser BUT without a 5th wire..... when the unit goes into defrost.... the electric reheats will not come on. Defrosting a heat pump means running it in A/C mode where it uses heat from inside the house to defrost the outside unit. That would allow cold air to flow inside the house.
Communicating means to do many functions on two or three data wires.
1) R - 24v power
2) C - common
3) Y - compressor
4) O/B - reversing valve.
So technically four wires will run your condenser BUT without a 5th wire..... when the unit goes into defrost.... the electric reheats will not come on. Defrosting a heat pump means running it in A/C mode where it uses heat from inside the house to defrost the outside unit. That would allow cold air to flow inside the house.
Communicating means to do many functions on two or three data wires.
#27
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The reversing valve is sharing the C wire with everything else 24V powered. So removing a wire means it’ll never receive 24V, and never switch to cooling.
R-24V Hot
C-24V Common for all components
O-Reversing valve
W-Auxiliary heat
Y-Compressor
R-24V Hot
C-24V Common for all components
O-Reversing valve
W-Auxiliary heat
Y-Compressor
#29
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No, you still need a common off the source transformer to power the coils. Can’t use the transformer inside for hot and another for common.
And you cannot have 2 different sources of control power within the outdoor unit.
And you cannot have 2 different sources of control power within the outdoor unit.
#31
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Yes, except for high end communicating models.
Have you thought out other details if your doing a DIY install? The power source for the air handler and electric heat? Special tools. How to properly size everything?
Have you thought out other details if your doing a DIY install? The power source for the air handler and electric heat? Special tools. How to properly size everything?
#34
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#35
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I don’t think that device is for heat pumps. It’s for when there’s no C wire.
Look at the photo. There’s no O terminal.
Look at the photo. There’s no O terminal.
#37
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What is this they are using. It looks to be on hp with 4 wire.
#38
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Do we need the R to have power for the control board? If so could I use a small 24v trans to connect R&C and still connect the C wire? That way I would free up the R wire.
R-24V Hot
C-24V Common for all components
O-Reversing valve
W-Auxiliary heat
Y-Compressor
R-24V Hot
C-24V Common for all components
O-Reversing valve
W-Auxiliary heat
Y-Compressor
#39
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Yes, it needs 24V, but cannot be a secondary source of power from the air handler control power source.
You can’t put a secondary transformer in like that.
You can’t put a secondary transformer in like that.
#40
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It would be like a center tap trans. The R & C would power the board. The C with the wire attached from handler trans witch power therm and handler would a complete circuit for O W Y on hp. I hope I'm not bothering you just trying to make this work.