White Rodgers 1F83-277, PART NO. 37-6509A Wiring Diagrams, Heat Pump Terminal Outputs

WIRING DIAGRAMS

NOTE

Polarity must be observed. If the HOT side of the second transformer is jumpered to the COMMON side of the first transformer a short will be made. Damage to equipment will occur when power is restored.

OBY2Y1G

	Reversing
Reversing	Valve	2nd Stage			Fan
	Energized in
Valve		Compressor			Relay
Energized in	Heat, Off,
Cool Mode	Emergency		Compressor
	Mode
				Contactor

E/W1

THERMOSTAT

W2

C

L

R

SYSTEM

Limit or

Limit or

Safety

HOT

Safety

24 VAC

120 VAC

Switches

Emergency

SYSTEM

Switches

or 1st Aux.

MONITOR

NEUTRAL

Stage Relay

SWITCH

24 VAC

Auxiliary

ACCESSORY

Heating

NOTE

Aux

RELAY N.O.

Transformer

The

accessory relay scheme

Relay

CONTACT

(Class II

is

required

when safety

(Stage 2)

Current Limited)

circuits exist in both systems.

COMMON

TWO COMMONS MUST

Limit or

Limit or

BE JUMPERED TOGETHER!

Safety

Safety

HOT

Switches

24 VAC

120 VAC

Switches

COMMON

NEUTRAL

Heat Pump Transformer

(Class II Current Limited)

Figure 4. Typical wiring diagram for two transformer heat pump systems with safety circuits in BOTH systems

Heat Pump Terminal Outputs

Refer to equipment manufacturers' instructions for specific system wiring information.

You can configure the thermostat for use with the following heat pump system types:

HEAT PUMP TYPE 1. Single stage compressor system; gas or electric backup.

This thermostat is designed to operate a single-transformer system. If you have a two-transformer system, cut and tape off

one transformer. If transformer safety circuits are in only one of the systems, remove the transformer of the system with NO safety circuits. If required, replace remaining transformer with a 75VA Class II transformer. After disconnecting one trans- former, the two commons must be jumpered together.

Use the terminal output information below to help you wire the thermostat properly for your multi-stage system. After wiring, see CONFIGURATION section for proper thermostat configu- ration.

				THERMOSTAT TERMINALS (HEAT PUMP)
SYSTEM	L	C	R	W2	E/W1	Y2	Y1	G	O	B
Heat	Malfunction	24 Volt	24 Volt	Heat Mode	Heat mode	No	Heat and	Blower/Fan Energized	Energized	Energized
Pump 1	Light	(Common)	(Hot)	3rd stage	2nd stage	Output	Cool mode	on call for Heat	in Cool	in Heat
				Emergency	or		1st stage	and Cool	Mode	OFF
Heat				mode	Emergency	2nd	(compressor)	Set GAS/ELEC switch		Emergency
Pump 2				2nd stage	Mode	stage		for Emergency mode		mode
					1st stage	compressor

O

Reversing

Valve

Energized in

Cool Mode

B	Y1		Y2	G
		Compressor
		Contactor
Reversing
		Stage 2
Valve
Energized in
Heat Mode	Compressor			Fan
Off Emergency	Contactor
				Relay
	Stage 1

E/W1

Heat

Relay

Stage 1

W2

Heat

Relay

Stage 2

THERMOSTAT

C R

SYSTEM

Hot

24 VAC 120 VAC

Neutral

TRANSFORMER

(Class II, Current Limited)

Figure 5. Typical wiring diagram for single transformer multi-stage systems

3