Fig.4-5
SERVICE VALVES
The stem or core is removable with a flexible seal at its base held closed with a spring. Schrader valves
allow a technician to connect gages to the system with a minimum loss of charge. Use a cap with an
5.ELECTRICAL CONTROL DEVICES
PROTECTION DEVICES
Protection for the unit begins with the installation of appropriate fuses or circuit breakers by the installing
OVERLOADS AND LIMITS
include the automatic reset internal overload in the fan motor and the compressor automatic reset
internal overload. Such controls are not serviceable but their operation may influence service
troubleshooting .For example, the compressor internal overload may stay open for several hours .A
refrigerant pressure exceeds a pre-determined limit of 440 to 460 p.s.i.g.
When pressure becomes
THERMOSTATS
In the cooling mode, the thermostat calls for cooling by energizing the compressor contactor and the
indoor blower control. The indoor blower can operate continuously by setting the thermostat subbase fan
switch to the “ON” position.
subbase selection information found in the wiring diagram booklet.
various manual changeover, auto changeover and set-back thermostats or see the thermostat and
accessible by the consumer. Contact your local distributor for information on part numbers of
or
“Schrader valve” and the refrigerant line valve. The Schrader valve is like a valve in an automobile tire.
inner seal to prevent leakage and keep dirt and moisture from entering the system.
systems, these valves also hold the charge in the outdoor section from factory.
Refrigerant control valves allow the outdoor unit to be isolated into from the balance of the system. In split
Thermostats are the most obvious control in the air conditioning system because these controls are
contractor. Breaker or fuse size is governed by the National Electrical Code and local code. AMP draw
Overloads protect against over-current or over-temperature conditions. Those located in the outdoor unit
requirements for each unit are found in the Specifications.
technician may incorrectly diagnose this as an open compressor winding.
The high pressure cut-out is a pressure activated switch. It opens an electrical circuit when the
HIGH PRESSURE CUT OUT SWITCH (optional) (Fig. 5-1)
normal, the
switch
restores automatically
.
Fig. 5 -1
REFRIGERANT CIRCUIT (Fig. 4-5)
All 13SEER units outdoor coils are multi-circuit. Refrigerent gas or liquid is uniformly distributed to from
There are two types of service valve used on these air conditioning units. They are the service port valve
4 to 10 circuits to improve heat transfer and reduce capacity losses due to pressure drops.
10
Central Air Conditi
oning
Model: Heat Pump,
HR13-D2
