These Ritetemp  thermostats work with Heat Pump Systems - 8010, 8050c, 8085c, 8082c

Refer to the guide below for specific applications.  If you know the specific manufacturer of your Heat Pump System CLICK HERE for specific wiring reference.

24VAC   HEAT PUMP WITHOUT AUXILIARY HEAT  4 WIRE   

The  drawing below is a heat pump without auxiliary heat.  This is useful with an air heat exchanger (outside unit) in mild climates like Florida and parts of Arizona. It is not very efficient much below 35F. Most areas require a heat pump with auxiliary (generally electric) heat to supplement the heat pump in cold weather.  If the heat exchanger is in the ground or in a well (hydro), it is very efficient and auxiliary heat is not necessary. Some high-rise apartments and condos circulate water through the building, warm in winter and cool in summer. This does not require auxiliary heat.
NOTE: Often this system requires a line voltage thermostat. For information on this, call Ritetemp @  1  888  515-2585

Notice the thermostats W (heat) and Y (cool) are connected together. This is because the compressor is used when the thermostat calls for heating (W) or cooling (Y). The terminals O or B control the changeover relay which determines if it will be heating or cooling.

In a heat pump, never connect both O and B or damage may result. See wiring pg 3.

NOTE: Some heat pumps use other letters for the changeover. Florida Heat Pump Co. uses the letter W on the old thermostat instead of O.  (Connect their W to the stats O)

For more background information about how heat pumps work go to: www.dhclimatecontrol.com/hp.htm

       24VAC   HEAT, FAN and COOL    5 wire (with separate heat & cool power)

The drawing below is a standard 24VAC, 5 wire heat and cool controls system. Some times, the heating and cooling systems have their own separate 24VAC power so there are two power sources, RC (cool and fan) and RH (heat).

The 24VAC HEAT transformer provides power to just the HEAT  relay.  The 24VAC COOL transformer provides power to the FAN relay and the COOL (compressor) relay.

When there are two power sources, the strap between RC and RH must be removed or damage may occur!  The RC wire and the RH wire must never touch each other.

It is important for the customer to turn off his power before he disconnects the old thermostat!

The 5 wire heating and cooling functions are the same as the 3 and 4 wire drawings. Note when there are two transformers, the C wire comes off of the HEAT transformer.

              24VAC  HEAT PUMP WITH AUXILIARY HEAT  5 WIRE

The drawing below is a heat pump with auxiliary heat.  The auxiliary heat is usually electric heat strips mounted in the air handler (fan). This type of system is typically used where there is no natural gas available in cool to cold climates.

The auxiliary electric heat comes on to help bring the house temperature up faster, and to supplement the heat pump when the outside temperature is cold (approx. 35F or below). When the outside temperature gets to low, the heat pump can frost up and quit working.

Most heat pump thermostats turn the auxiliary electric heat on when the target temperature gets 2F or more above the room temperature. The electric heat strips use much more electricity than the heat pump.

The Ritetemp thermostats for heat pumps with AUX heat must have the GAS/ELECT jumper in the ELECT position (fan comes on with the AUX heat).

The auxiliary heat is also used in an emergency if the heat pump quits or just can't keep up. When the thermostat is switched to EMER, the heat pump is shut off and only the AUX heat is used.