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On a heat pump the difference between haet and cool is the reversing valve

On a heat pump the difference from heat to cool is the reversing valve.
In cooling or heating the Y1 terminal will always be energized, this is the contactor.
Depending on brand the reversing valve will either be energized in Heat or Cool. At the outdoor unit check to see if the reversing valve is getting 24 volts in cool, if not check to see if it is getting 24 volts in heating. The easiest way to check if the reversing valve is shifting, is to feel the big copper tube, (it is not the suction line on a heat pump) this is a refrigerant vapor line. It will be cold in cooling and hot in heating.
Check your thermostat installation instructions and heat pump installation instructions to determine the proper terminal designations for your heat pump and thermostat. There are some brands out there that use the B terminal as common to the 24 volt circuit, so you have to check the wiring and make sure this is not common.
If it is energized in Cool then the Y1 and O terminal will be energized. You will have 24 volts from common usually the C terminal to Y1 and O.
If it’s energized in Heat then the Y1 and B terminal should be energized. You will have 24 volts from common usually the C terminal to Y1 and B.
If you get heat when you’re calling for cooling or vice versa then switch the wire between the B and O terminals.

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We have 2 furnaces in our house, both on the braeburn 3200 model thermostats.


If you have a dual fuel system - gas/heat pump the heat pump should lock out at around 41 degrees depending on what the outside lockout sensor is set at. It may be that both the heat pump and furnace could be running at the same time if the outside lockout isn't working or there could be a problem with the thermostat. Best bet would be to have a service tech check it out. However if you want to check it out here are the terminals Terminations: R,Y1,Y2,W2,E,G,O,B,L,C. W2, E and B are the heating terminals for 2nd stage heat and emergency heat. First stage heat, compressor Y1 with B (reversing valve on heat pump) energized together. 2nd stage W2 energized for gas or electric heat . No power to Y1 and B when W2 is energized if gas. E can be energized with Y1 and B if you have electric heat or if you switch over to emergency heat, E will be energized.

Feb 02, 2016 | Heating & Cooling

1 Answer

I have a new 13 seer rheem 4 ton heat pump system the heat pump won't turn on in heat or in other words it is only working in cooling mode I wired it according to the schematic


On a heat pump the difference from heat to cool is the reversing valve.
In cooling or heating the Y1 terminal will always be energized, this is the contactor.
Depending on brand the reversing valve will either be energized in Heat or Cool. At the outdoor unit check to see if the reversing valve is getting 24 volts in cool, if not check to see if it is getting 24 volts in heating. The easiest way to check if the reversing valve is shifting, is to feel the big copper tube, (it is not the suction line on a heat pump) this is a refrigerant vapor line. It will be cold in cooling and hot in heating.
Check your thermostat installation instructions and heat pump installation instructions to determine the proper terminal designations for your heat pump and thermostat. There are some brands out there that use the B terminal as common to the 24 volt circuit, so you have to check the wiring and make sure this is not common.
If it is energized in Cool then the Y1 and O terminal will be energized. You will have 24 volts from common usually the C terminal to Y1 and O.
If it’s energized in Heat then the Y1 and B terminal should be energized. You will have 24 volts from common usually the C terminal to Y1 and B.
If you get heat when you’re calling for cooling or vice versa then switch the wire between the B and O terminals.

Feb 02, 2010 | Heating & Cooling

1 Answer

Gold Star mini split heat pump 24,000 btu. Changed indooe as we as outdoor boards and still goes in cooling mode only. Reset button on outdoor board calls in heat but not by inside hand set. Len Cabana Techno Refrig. Inc. PS: Sometimes indoor green light flashes five times. Close power breaker and try again with inside hand set. Still no heat or fan on.


On a heat pump the difference from heat to cool is the reversing valve.
In cooling or heating the Y1 terminal will always be energized, this is the contactor.
Depending on brand the reversing valve will either be energized in Heat or Cool. At the outdoor unit check to see if the reversing valve is getting 24 volts in cool, if not check to see if it is getting 24 volts in heating. The easiest way to check if the reversing valve is shifting, is to feel the big copper tube, (it is not the suction line on a heat pump) this is a refrigerant vapor line. It will be cold in cooling and hot in heating.
Check your thermostat installation instructions and heat pump installation instructions to determine the proper terminal designations for your heat pump and thermostat. There are some brands out there that use the B terminal as common to the 24 volt circuit, so you have to check the wiring and make sure this is not common.
If it is energized in Cool then the Y1 and O terminal will be energized. You will have 24 volts from common usually the C terminal to Y1 and O.
If it’s energized in Heat then the Y1 and B terminal should be energized. You will have 24 volts from common usually the C terminal to Y1 and B.
If you get heat when you’re calling for cooling or vice versa then switch the wire between the B and O terminals.

Feb 01, 2010 | LG LS-K2430HL Heat Cool Mini Split Air...

1 Answer

the thermostat on my coleman heat pump has 7 wires labled:g,y1,w1,x,w2,a,r. but the hunter replacement thermostat i purchaced does not have the same labeling it has rc/r,c,y1,y2,w2,e,o,b,g,l.i need to know what coleman designates to each lable


here is some info may help you
coleman = Hunter
g   =  g
y1 =  y1
     =  y2 (second stage you don't have it on your system)
r    =  rc/r (leave the jumper bewteen rc/r)
x   =  c
w1 =  w1
w2 =  w2
a   =  o
     =  b
the "b" terminal is to energized the revensing valve on heat mode
the "o" terminal is to energized the reversing valve on cool mode

Oct 09, 2009 | Heating & Cooling

1 Answer

White-Rodgers 1F58-58 to Hunter 44660


This is the corrcet wiring:
G - G fan relay
R - RC1, RC put a jumper RH ( to supply power to the cool and heat)
L - no wire connected (malfunction indicator) tape- off that wire
E - Emergency heat relay
B - W/B ( reversing valve in your heat pump energized during heat )
W2 - Auxilliary heat
Y - Y1 ( compressor contact)
O- Y/O ( reversing valve is energized during cool)
make sure that the system selector is on heat pump position.

Apr 30, 2009 | Hunter Fan Company 5/1/1 Programmable...

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