Carrier 50HQP072-120 specifications Install Field Control Wiring, Jumper Locations

Step 10 — Install Field Control Wiring

THERMOSTAT CONNECTIONS — The thermostat should be wired directly to the Aquazone™ control board. See Fig. 18 and 19.

The thermostat should be located on an interior wall in a larger room, away from supply duct drafts. DO NOT locate the thermostat in areas subject to sunlight, drafts or on external walls. The wire access hole behind the thermostat may in cer- tain cases need to be sealed to prevent erroneous temperature measurement.

Position the thermostat back plate against the wall so that it appears level and so the thermostat wires protrude through the middle of the back plate. Mark the position of the back plate mounting holes and drill holes with a 3/16-in. bit. Install sup- plied anchors and secure plate to the wall. Thermostat wire must be 18 AWG (American Wire Gage) wire. Wire the appro- priate thermostat as shown in Fig. 20 and 21 to the low voltage terminal strip on the Complete C or Deluxe D control board.

Most heat pump thermostats will work with a Carrier unit, provided the thermostat has the correct number of heating and cooling stages.

WATER FREEZE PROTECTION — The Aquazone control allows the field selection of source fluid freeze protection points through jumpers. The factory setting of jumper JW3 (FP1) is set for water at –1.1 C. In earth loop applications, jumper JW3 should be clipped to change the setting to –12.2 C when using antifreeze in colder earth loop applications. See Fig. 18.

AIR COIL FREEZE PROTECTION — The air coil freeze protection jumper JW2 (FP2) is factory set for –1.1 C and should not need adjusting.

TERMINAL STRIP P2

C

TYPICAL

24 VAC WATER VALVE

A

Fig. 19 — Typical Aquazone Accessory Wiring

(Control D Shown)

WATER SOLENOID VALVES — Water solenoid valves may be used on variable flow systems and ground water installa- tions. A typical well water control valve wiring which can limit waste water in a lockout condition is shown in Fig. 18. A slow closing valve may be required to prevent water hammer. When using a slow closing valve, special wiring conditions need to be considered. The valve takes approximately 60 sec- onds to open (very little water will flow before 45 seconds) and it activates the compressor only after the valve is completely opened by closing its end switch. When wired as shown, the valve will have the following operating characteristics:

1.Remain open during a lockout.

2.Draw approximately 25 to 35 VA through the “Y” signal of the thermostat.

IMPORTANT: The use of a slow-closing water solenoid valve can overheat the anticipators of electromechanical thermostats. Only use relay based electronic thermostats.

ACCESSORY CONNECTIONS — Terminal labeled A on the control is provided to control accessory devices such as water valves, electronic air cleaners, humidifiers, etc. This sig- nal operates with the compressor terminal. See Fig. 19. Refer to the specific unit wiring schematic for details.

NOTE: The A terminal should only be used with 24 volt signals — not line voltage signals.

THERMOSTAT

Compressor-Stage 1	Y1
Compressor-Stage 2	Y2
Reversing Valve	O
Fan	G
24Vac Hot
	R
24Vac Com	C
	AL

CompleteC 1 CompleteC 2

Y	Y
O	O
G	G

RR

CC

AL AL

Fig. 20 — Thermostat Wiring to Complete C Board

a50-6268tf.tif

AQUAZONE CONTROL (Complete C Control Shown)

Fig. 18 — Typical Aquazone™ Control Board

THERMOSTAT

Compressor-Stage 1	Y1
Compressor-Stage 2	Y2
Reversing Valve	O
Fan	G
24Vac Hot	R
24Vac Com	C
	AL

Deluxe D 1		Deluxe D 2
Y1	COM 2	Y COM 2
Y2
O		O
G		G

RR

CC

AL1 AL1

Jumper Locations

Fig. 21 — Thermostat Wiring to Deluxe D Board

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