[mooney99]

Had a Heat Pump fan problem which was solved by replacing both fan and motor. System runs great (hot air) but my 20 KW elements also run all the time when heat is on. My thermostat is four-wire without aux and emer. settings but I did have the correct changeover thermostats when the system was installed. The Trane "specialists" came out, changed the thermostats (2) and never came back. I also have zone damper control unit (2 zones, I think). They apparently wired the system to have the heat elements on all the time with heat.
My question is how can I use heat pump heat only except for very cold days and nights. What wires and where should I change. THANKS!

[Fastlanedan]

You need a thermostat that has two stage heating. you will also need new thermostat wire, mininum 6 wire, (I recommend installing 8 wire for future add one, Example: you might have two stage cooling, and 2 stage heating, plus zone control)

[John @ Fischers]

Do you have 2- Double pole 220V breakers at the air handler? Cut them off and the heat strips should not come on. Hopefully that didn't wire the blower into this power source.

Turn them off and then try the heat and see if the blower on the air handler still comes on, if so, then see if the strips are off and the outside unit is still running.

Post back.

[mooney99]

Originally Posted by John @ Fischers

Do you have 2- Double pole 220V breakers at the air handler? Cut them off and the heat strips should not come on. Hopefully that didn't wire the blower into this power source.

Turn them off and then try the heat and see if the blower on the air handler still comes on, if so, then see if the strips are off and the outside unit is still running.

Post back.

Thanks, yes I can cut off the 2-Double Pole breakers at the Air Handler but they do have the blower motor wired to one of the sources. Great help on the thermostat but I think there are many more wires not used
at the room thermostats as I orginally had the correct thermostats-

[mooney99]

Originally Posted by mooney99

Thanks, yes I can cut off the 2-Double Pole breakers at the Air Handler but they do have the blower motor wired to one of the sources. Great help on the thermostat but I think there are many more wires not used
at the room thermostats as I orginally had the correct thermostats-

At the heat source I have the 2 double pole breakers that feed the two contactors-can I disconnect the three small white wires to the sides of the contactors (24V) and the system still work with Heat Pump? These wires seem to come from the PCB/ Fan Relay board-

[hvac_hillbilly]

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[hvac_hillbilly]

Originally Posted by hvac_hillbilly

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i would suggest an outdoor thermostat set for 35 degrees outdoor ambient to bring on heat strips with unit at that tempture this will improve the overall fuction of your system as the heatpump starts to become inefficent at this out door temp you will need no more wires between thermostat and indoor unit however you will need a total of a total of 5 wire from indoor unit to outdoor unit

[mooney99]

Originally Posted by hvac_hillbilly

i would suggest an outdoor thermostat set for 35 degrees outdoor ambient to bring on heat strips with unit at that tempture this will improve the overall fuction of your system as the heatpump starts to become inefficent at this out door temp you will need no more wires between thermostat and indoor unit however you will need a total of a total of 5 wire from indoor unit to outdoor unit

Thanks for your help- Is this thermostat in the Heat Pump control panel? Can this thermostat be manually set or do I buy one that is preset?
I have one thermostat ( hanging at the bottom with two wires) but can't find the other thermostat unless it is on the PCB Defrost Control Board-

[hvac_hillbilly]

Originally Posted by mooney99

Thanks for your help- Is this thermostat in the Heat Pump control panel? Can this thermostat be manually set or do I buy one that is preset?
I have one thermostat ( hanging at the bottom with two wires) but can't find the other thermostat unless it is on the PCB Defrost Control Board-

this would be an add on outdoor themostat that you would have to mount to the outdoor unit
i like rancho it has a set of normally opened and a set of normally closed contacts to wire (i know i pprobaly get a lot of disagreement on this but t does work) come off the yellow wire to the contactor through open contacts to white wire to heatsrips make sure you hook up the white wire to the defrost board so the strips come on in defrost going to look for diagram

[hvac_hillbilly]

Originally Posted by Fastlanedan

You need a thermostat that has two stage heating. you will also need new thermostat wire, mininum 6 wire, (I recommend installing 8 wire for future add one, Example: you might have two stage cooling, and 2 stage heating, plus zone control)

before we rehook the heat strips we need them off can you tell me how the thermostat is wired
r=red to 24 volt side of contactor
y=yellow to contactor outside unit
o=orange to reversing vavle
g=green to fan relay
w should be jumped to y for this applacation