Therma-Stor Products Group UA-135H - Manual (Page 16)

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only the impeller fan should run. Disconnect the wires.
3. Connect the yellow and blue pigtails from the main unit together;
the compressor and impeller fan should run.
4. If these tests work, the main unit is working properly. You should
check the control panel and field control wiring for problems next.
5. Remove the control panel from the mounting box and detach
it from the field installed control wiring. Connect the blue,
yellow, and green wires from the control panel directly to the
corresponding colored pigtails on the main unit. Leave the violet,
white and red wires disconnected!
6. Turn on the fan switch; the impeller fan should run. Turn off the
fan switch.
7. Turn on the humidity control; the compressor and impeller fan
should run.
8. If these tests work, the problem is most likely in the field control
wiring.
6.3 Refrigerant Charging
If the refrigerant charge is lost due to service or a leak, a new charge
must be accurately weighed in. If any of the old charge is left in the
system, it must be recovered before weighing in the new charge.
Refer to the unit nameplate for the correct charge weight and
refrigerant type.
6.4 Impeller Fan Replacement
The motorized impeller fan is a unitary assembly consisting of the
motor and impeller fan. If defective, the complete assembly must be
replaced.
1. Unplug the power cord
2. Remove the cabinet access panel
3. Disconnect the impeller's blue, black, brown leads, which are
attached to the capacitors as well as the green/yellow ground
lead.
4. Remove the impeller access plate, which is the D-shaped plate
mounted to the supply/exhaust panel of the UA-135H. The
impeller should be attached to this D-shaped plate. Pull the leads
through the black plastic scroll housing inside, as you remove the
impeller access plate.
5. Remove the two cable clamps securing the impeller cord to the
access plate.
6. Remove the defective impeller from the access plate
7. Reassemble the new impeller fan by reversing the above
procedure. Note: Make sure that the new impeller cord is secured
tightly to the impeller access plate utilizing the two cable clamps
given with the unit. Make sure to reconnect all leads in their
correct positions.
6.5 Compressor/Capacitor Replacement
This compressor is equipped with a two terminal external overload
and a run capacitor, but no start capacitor or relay.
CAUTION-ELECTRICAL SHOCK HAZARD: Electrical power must be
present to perform some tests. These tests should be performed
by a qualified service person.
6.6 Replacing a Compressor, Nonburn Out
Remove the refrigerant from the system. Replace the compressor
and liquid line filter/drier. Charge the system to 50 PSIG and check
for leaks. Remove the charge and weigh in the refrigerant quantity
listed on the nameplate. Operate the system to verify performance.
6.7 Electric Ventilation Damper
The electric ventilation damper is controlled by the ventilation timer.
The damper will open when the ventilation timer is activated to
allow fresh air into the structure through the 6" diameter fresh air
inlet duct. The electric ventilation damper will remain closed when
the ventilation timer is not activated to prevent over-ventilating
the structure when the unit is dehumidifying or recirculating the
indoor air. The electric ventilation timer operates on 24 Vac from the
control circuit. DO NOT connect high voltage to the damper motor
or damage to the motor may result. DO NOT force the blade of the
damper by hand or damage to the damper motor may result.
The damper opens in one direction only. The damper rotates very
slowly, allow sufficient time for the damper to cycle. The damper will
take approximately 1 minute to cycle from closed to open or from
open to closed.
If the electric ventilation damper fails to operate:
1. Check that the wiring is correct and that voltage is present at the
damper motor.
2. Check for any obstruction inside the damper. If the electric
ventilation damper fails to operate after performing these checks,
it must be replaced.
6.8 Condensate Pump Kit
An optional condensate pump kit is available from the factory for use
with the UA-135H. Condensate is automatically pumped to a remote
location when the water level in the
pump's reservoir rises to close the
float switch. The pump also contains
a safety float switch. The white leads
from this switch extend from beneath
the pump cover. This switch should
be installed in series with the field
wire that connects the blue (#5) lead from the UA-135H to the blue
(#5) lead on the control panel. If the pump fails, this switch opens
the compressor control circuit and stops water production before
the reservoir overflows. The UA-135H will continue to ventilate or
circulate air as normal, but will not dehumidify until this switch
closes.
Ultra-Aire 135H Installer’s & Owner’s Manual
FOR HVAC INSTALLER AND HOMEOWNER