Service manual

Section 7 Electrical Specifications
7-1
Section 7
Electrical Specifications
Main Power Switch
Function
Switches power to the reach-in on and off.
Specifications
Double pole single throw (DPST)
Check Procedures
1. Check for proper line voltage (+/– 10%).
2. Inspect the switch for proper wiring.
3. Inspect the terminals for clean, tight
connections.
4. Check across the switch terminals with a
voltmeter. Replace the switch if you do not
obtain the results below:
Switch Position Voltage
On 0
Off Line
Temperature Control (Thermostat)
Function
Opens and closes to start and stop the compressor
and condenser fan(s) to maintain a constant cabinet
temperature.
Specifications
Constant differential
Range 0°± 2°F (-17.8° ± -16.7°C) / 5°± 2°F (-15° ±
-16.7°C)
Check Procedures
If the reach-in continues to run in the cooling cycle:
1. Turn the temperature control to the warmest
setting.
2. Hook a voltmeter across the temperature control
terminal leads.
3. If the voltmeter reads line voltage, the control
has opened and is functioning normally. If the
control fails to open, replace it.
If the reach in does not run:
1. Disconnect electrical power supply.
2. Turn the temperature control to the coldest
setting.
3. Isolate the temperature control and hook an
ohmmeter across the terminals.
4. If the ohmmeter registers continuity, the control
is good.