Trane Precedent THC036E, Installation And Maintenance Manual

Page: 47 / 64

Start-Up
RT-SVX22J-EN 47
3. Verify that the dampers stroked to the full open
position.
4. To stop the SERVICE TEST, turn the main power
disconnect switch to the “Off” position or proceed to
the next component start-up procedure. Remove
electro mechanical test mode connections (if
applicable).
Compressor Start-Up
1. Attach a set of service gauges onto the suction and
discharge gauge ports for each circuit. Refer to the
refrigerant circuit illustration in the Service Facts.
ReliaTel Control.
Momentarily jump across the Test 1 &
Test 2 terminals on LTB1 one additional time if
continuing from previous component start-up or until
the desired start-up component Test is started.
Electro Mechanical Control.
Using the Service Test
Guide perform the proper test mode connections.
Scroll Compressors.
a. Once each compressor has started, verify that the
rotation is correct. If a scroll compressor is rotating
backwards, it will not pump and a loud rattling
sound can be observed.
b. If the electrical phasing is correct, before
condemning a compressor, interchange any two
leads (at the compressor Terminal block) to check
the internal phasing. If the compressor runs
backward for an extended period (15 to 30 minutes),
the motor winding can overheat and cause the
motor winding thermostat to open.
2. After the compressor and condenser fan have started
and operated for approximately 30 minutes, observe
the operating pressures. Compare the operating
pressures to the operating pressure curve in the
Service Facts.
3. Check system superheat. Follow the instruction listed
on the superheat charging curve in the Service Facts.
Superheat should be within ±5ºF of the superheat chart
value.
4. Repeat steps 1 through 4 for each refrigerant circuit.
5. To stop the SERVICE TEST, turn the main power
disconnect switch to the “Off” position or proceed to
the next component start-up procedure. Remove
electro mechanical test mode connections (if
applicable).
Dehumidification Option
Momentarily jump across the Test 1 and Test 2 terminals of
the LTB1 until the unit enters test mode 7. (See
Table 9,
p. 42 ). Once the unit is in the reheat test mode, verify that
the 3 way valve has shifted to the reheat position and that
the supply temperature rises 10 ºF more than when in
cooling mode stage 2.
Monitor the suction pressure for 15 minutes. The suction
pressure should remain within 5 psi of normal cooling
operation. If the unit has a 2 speed outdoor fan and if the
outdoor air temperature is below 70°F, verify that the OD
fan is in low speed.
1. Clamp an amp meter around one of 1st stage heater
power wires at the heater contactor.
ReliaTel Control.
Using the Service Test Guide in
Table 9, p. 42 , continue the SERVICE TEST start-up
procedure for each compressor circuit.
Momentarily jump across the Test 1 & Test 2 terminals
on LTB one additional time if continuing from previous
component start-up or until the desired start-up
component Test is started.
Electro Mechanical Control.
Using the Service Test
Guide perform the proper test mode connections;
2. Verify that the heater stage is operating properly.
3. Clamp an amp meter around one of 2nd stage heater
power wires at the heater contactor (if applicable).
ReliaTel Control.
Using the Service Test Guide in
Table 9, p. 42 , continue the SERVICE TEST start-up
procedure for each compressor circuit. Momentarily
jump across the Test 1 & Test 2 terminals on LTB one
additional time if continuing from previous
component start-up or until the desired start-up
component Test is started.
WARNING
Live Electrical Components!
During installation, testing, servicing and
troubleshooting of this product, it may be necessary to
work with live electrical components. Have a qualified
licensed electrician or other individual who has been
properly trained in handling live electrical components
perform these tasks. Failure to follow all electrical
safety precautions when exposed to live electrical
components could result in death or serious injury.
WARNING
Live Electrical Components!
During installation, testing, servicing and
troubleshooting of this product, it may be necessary to
work with live electrical components. Have a qualified
licensed electrician or other individual who has been
properly trained in handling live electrical components
perform these tasks. Failure to follow all electrical
safety precautions when exposed to live electrical
components could result in death or serious injury.