Reznor R6GD Option - Installation - Low Pressure Switch - Manual (Page 2)

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INTRODUCTION - Low Pressure Cut-Out Kit 913551
The Low Pressure Cutout Kit is designed for use in single package air-conditioners and heat pumps, split system air-
conditioners and heat pumps, and gas electric products. The kit consists of a pressure switch, a service adapter tee
and miscellaneous parts for mounting. The pressure switch opens when the suction pressure drops below 25 psig and
closes again when the suction pressure rises above 50 psig. Opening of the switch stops the compressor and initiates
the 5 minute compressor delay. The system will not start again until the suction pressure rises above 50 psig and a 5
minute time period has expired.
INSTALLATION SEQUENCE
The installation sequence is as follows:
1. Read these installation instructions completely before
proceeding.
2. Disconnect all power to the unit.
3. At the front of the unit remove the service panel to the
control box. This will have all of the electrical control
components within and in the case of the R4 units the
gas control components as well.
4. Remove the front panel with the service ports and
drain tube opening from the unit.
5. There are two service valves on the unit. Locate the
one in the 3/4" or 7/8" diameter compressor suction
line.
6. Remove the cap from the service valve. Mount the
pressure switch on the service valve and tighten. If
desired, a service adapter tee is supplied with the kit
to keep a service port available. Be sure that the
service valve cores shipped with the kit are inserted
in the valve bodies before proceeding. If used, place
the cap removed from the service valve on the
service adapter tee.
7. Route the two wire leads from the switch through the
wire grommet at the top of the panel separating the
compressor from the control box.
8. Terminate one of the leads with the insulated 1/4"
female push on terminal. Terminate the other lead
with the insulated 1/4" male terminal. Both terminals
are supplied with the kit.
9. Find the orange wire currently in the unit running from
the economizer plug to the anti short cycle timer
(single phase air conditioners), contactor (three
phase air conditioners), or defrost board (heat pumps).
Remove this orange lead from the anti short cycle
timer, contactor or defrost board as appropriate.
Replace the uninsulated terminal on this wire with a
insulated 1/4" female terminal provided in the kit.
Connect this insulated female terminal to the
insulated male terminal on one of the pressure
switch leads. Connect the insulated female terminal
on the other pressure switch lead to the anti short
cycle timer, contactor, or defrost board as appropriate.
10. SPLIT SYSTEMS: Refer to the appropriate wiring
diagram in these installation instructions. For air
conditioners, wire pressure switch in series with T1 of
anti-short cycle timer and indoor thermostat (yellow
wire) as shown in the wiring diagram. For heat pumps,
remove and discard yellow jumper wire currently
between T1 and Y on the defrost control board.
Connect one lead of the pressure switch to T1 and the
other lead to Y of the same board.
11. If you are installing a low pressure switch or other
limiting device in addition to the high pressure switch
in this kit, wire the switches as shown below.
12. Insure the unit is wired up as shown in the wiring
diagram in this kit.
13. Tie wires back as necessary.
14. Replace all removed panels.
15. Test operation of unit.
WARNING:
To avoid risk of electric shock, personal injury,
or death, disconnect electrical power to the
unit before performing any maintenance or
service. The unit may have more than one
electric power supply.
!