ASPT Service Manual
Table Of Contents
- IMPORTANT INFORMATION
- PRODUCT IDENTIFICATION
- Checking Voltage
- Checking Wiring
- Checking Thermostat And Wiring
- Thermostat Wiring
- Checking Transformer And Control Circuit
- Checking Contactor And/Or Relays
- Checking Contactor Contacts
- Checking Fan Relay Contacts
- Checking Loss Of Charge Protector (Heat Pump Models)
- Checking High Pressure Control
- Checking Low Pressure Control
- Copeland Comfort Alert™ Diagnostics - 3-Wire module
- Copeland Coresense™ Diagnostics - 3-Wire module
- Checking Capacitor
- Resistance Check Using A Digital Multi-Meter
- Capacitance Check Using A Digital Multi-Meter (In Capacitance Mode)
- Testing a Run Capacitor Under Load
- Checking Outdoor Fan and Blower Motors (PSC Motors)
- Checking Fan and Blower Motor (ECM Motors)
- Checking ECM Motor Windings
- ECM CFM Adjustments MBE/AEPF
- Blower Performance Data
- Checking High Efficiency Motors
- EEM Blower Replacement
- MBR/AR*F Electronic Blower Time Delay Relay
- Checking Compressor
- Resistance Test
- Ground Test
- Unloader Test Procedure
- Operation Test
- Checking 3-Phase Scroll Compressor Rotation
- Testing Crankcase Heater (Optional Item)
- Checking Reversing Valve and Solenoid
- Testing Defrost Control
- Testing Defrost Thermostat
- Checking Heater Limit Control(s)
- Checking Heater Elements
- Electric Heater (Optional Item)
- Checking Heater Limit Control(s)
- Checking Heater Elements
- Refrigeration Repair Practice
- Leak Testing (Nitrogen or Nitrogen-Traced)
- Evacuation
- Charging
- Checking Compressor Efficiency
- Overfeeding
- Underfeeding
- Checking Superheat
- Subcooling on Expansion Valve System
- Checking Expansion Valve Operation
- Checking Restricted Liquid Line
- Overcharge Of Refrigerant
- Non-Condensables
- Compressor Burnout
- Refrigerant Piping
- Duct Static Pressures
- Single Piece Air Handler External Static
- Two Piece Air Handler External Static Pressure
- Furnace External Static Pressure
- Periodic Maintenance
SERVICING
94
After the refrigerant charge has bled into the system,
open the liquid service valve. The service valve cap is
the secondary seal for the valve and must be properly
tightened to prevent leaks. Make sure cap is clean and
apply refrigerant oil to threads and sealing surface on
inside of cap. Tighten cap nger-tight and then tighten
additional 1/6 of a turn (1 wrench at) to properly seat the
sealing surfaces.
HSVTC evaporator coil or air handler and 15 feet of line
set is supplied with the outdoor unit.
EXPANSION VALVE SYSTEM
only.
conditions 55º to 60ºF. Use the following guidelines
the refrigerant charge is within limits. Charge the unit
on low stage.
Superheat
adjusted only if necessary.
1. Purge gauge lines. Connect service gauge manifold to
base-valve service ports. Run the system in low stage at
least 10 minutes to allow pressure to stabilize.
2. Temporarily install a thermometer on the liquid line at the
liquid line service valve and 4-6” from the compressor on
the suction line. Ensure the thermometer makes adequate
contact and is insulated for best possible readings. Use
liquid line temperature to determine subcooling and vapor
temperature to determine superheat.
3. Check subcooling and superheat. Systems with TXV
application should have a subcooling of 5 to 7°F and
superheat of 7 to 9 °F.
decrease.
4. If subcooling and superheat are low, adjust TXV to 7 to
9 ºF superheat, and then check subcooling.
5. If subcooling is low and superheat is high, add charge to
raise subcooling to 5 to 7 °F then check superheat.
6. If subcooling and superheat are high, adjust TXV valve to
7 to 9 ºF superheat, then check subcooling.
7. If subcooling is high and superheat is low, adjust TXV
valve to 7 to 9 ºF superheat and remove charge to lower
the subcooling to 5 to 7 ºF.
pressure unless there is a gross undercharge.
8. Disconnect manifold set, installation is complete.
SUBCOOLING FORMULA = SATURATED LIQUID TEMP. -
LIQUID LINE TEMP.
HEAT PUMP - HEATING CYCLE
The proper method of charging a heat pump in the heat
mode is by weight with the additional charge adjustments
for line size, line length, and other system components.
For best results on outdoor units with TXVs, superheat
should be 2-5°F at 4-6” from the compressor. Make nal
charge adjustments in the cooling cycle.
The reason for compressor ineciency is broken or
damaged scroll anks on Scroll compressors, reducing the
ability of the compressor to pump refrigerant vapor.
The condition of the scroll anks is checked in the following
manner.
1. Attach gauges to the high and low side of the system.
2. Start the system and run a “Cooling Performance Test.
If the test shows:
a. Below normal high side pressure.
b. Above normal low side pressure.
c. Low temperature dierence across coil.
d. Low amp draw at compressor.
And the charge is correct. The compressor is faulty -
replace the compressor.
Overfeeding
Overfeeding by the expansion valve results in high suction
pressure, cold suction line, and possible liquid slugging of
the compressor.
If these symptoms are observed:
1. Check for an overcharged unit by referring to the cooling
performance charts in the servicing section.
2. Check the operation of the power element in the valve as
explained in Checking Expansion Valve Operation.
3. Check for restricted or plugged equalizer tube.