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HEAT PUMP
KITS AND ACCESSORIES
507308-01
2/2014
Supersedes 504,567M
MILD WEATHER CONTROL
KIT
INSTALLATION INSTRUCTIONS FOR MILD WEATHER CONTROL KIT (11B97) (612651-01)
USED ON HEAT PUMP UNITS
WARNING
Improper installation, adjustment, alteration, service or
maintenance can cause personal injury, loss of life, or
damage to property.
Installation and service must be performed by a qualified
installer or service agency.
WARNING
Electric Shock Hazard. Can cause injury
or death. Unit must be grounded in
accordance with national and local
codes.
Line voltage is present at all components
when unit is not in operation on units with
single‐pole contactors. Disconnect all
remote electric power supplies before
opening access panel. Unit may have
multiple power supplies.
Shipping and Packing List
Package 1 of 1 contains:
1 - Pressure switch (for HCFC-22 units [100087-07])
1 - Pressure switch (for HFC-410A units [100087-08])
1 - Relay (XP17 and XP21 models - K159) [69J8001]
1 - Valve depressor tee
1 - Protective conduit for wires (12” in length)
8 - Wire nuts
2 - Screws
4 - 18 gauge wires
Application
This kit should be applied to heat pump units operating in
the heating mode during mild weather conditions. The mild
weather pressure switch automatically cycles the outdoor
fan motor when the head pressure rises above normal op
erating conditions. The cutout point on this control is below
that of the high pressure switch, thereby eliminating nui
sance high pressure cutouts.
Installation
1. Disconnect all power to unit.
2. Select appropriate (HCFC-22 or HFC-410A) mild
weather pressure switch. Connect the pressure switch
to the open connection of the provided tee
before
con
necting the tee to the vapor valve.
3. Install the valve depressor tee on the vapor valve ser
vice port with the mild ambient pressure switch at
tached. Run wires through provided conduit for protec
tion (see figure 1).
4. Connect wire terminals of mild weather pressure
switch (and relay as needed) as shown in typical wiring
connections diagram (figures 2 through 8).
5. Restore power to unit.
TO
REVERSING
VALVE
VAPOR LINE
(TO INDOOR
COIL)
MILD WEATHER PRESSURE
SWITCH
NEW SERVICE
PORT
CAUTION
- Connect pressure switch to open side of tee
before
connecting tee to vapor valve.
VALVE
DEPRESSOR
TEE
CONNECT WIRES PER WIRING DIAGRAM (SEE FIGURE 2)
VAPOR LINE SERVICE VALVE (TOP VIEW)
USE PROVIDED CONDUIT TO PROTECT MILD WEATHER
PRESSURE SWITCH WIRING.
Figure 1. Typical Switch Installation
TO
CONTACTOR
TO RUN
CAPACITOR
TO
DEFROST
CONTROL
MILD
AMBIENT
SWITCH
FAN
MOTOR
Purple
Black
Orange
Figure 2. Typical Wiring Connections
Figure 3. K159 Relay Terminal Designation
