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cnecox
Oct 26, 2009, 08:39 AM
I just purchased a rheem rqpm series 4ton packaged heat pump and a honeywell pro th4210d thermostat. I had 15 kwatt heat strips installed in the heatpump as I live in norther Florida where the temp might drop to 20 degrees occasionally. I am unclear as to how to connect the thermostat. The wires coming from the heatpump unit are red, yellow, blue, green, white, and brown. The thermostat terminals are as such:

E Aux Y G O L R B C

C = 24 vac common "Optional 24 Vac common connection"

B = Changeover valve energized in heating "use either O or B terminals for changeover valve"

R = Power "Power supply. Provede disconnect means and overload protection as required"

L = Sends output when set to Em Heat "L terminal sends a continuous output when thermostat is set to Em. Heat. Connect to honeywell zoning panels to switch the panel to Emergency Heat.

O = Changeover valve energized in cooling "Use either O or B terminals for changeover valve"

G =Fan relay

Y = Compressor contactor

Aux =Auxillary heat relay-"install field jumper between Aux and
E if there is no emergency heat relay"

E =Emergency heat relay "same as Aux"

The heatpump installation manual shows the thermostat connection as such:

Thermostat Base to------- Unit Control
R... Red
w2... PR (I believe this should be White as there is no purple lead from the unit.
X... Brown
B... Blue
Y... Yellow
G... BK/GR

I don't believe I have an Emergency heat relay and there is no outdoor thermostat. A note in the heatpump manual says if these are not used, a jumper from W2 and E can be installed to transfer control of heating to the first stage when the system switch is in the Em Heat position.

I believe my basic question is how do I connect the brown wire and the white wire and do I need to install a jumper wire?