TRUE
glass
door
merchandisers
-
health
safety
timer
www
.
truemfg
.
com
TEC_TM_020 REV. A
07/9/2020
Page 13 of 20
ELECTRONIC CONTROL GENERAL SEQUENCE OF OPERATION -
HEALTH SAFETY TIMER (HST) MODELS
1. Cabinet is plugged in.
a. Display will illuminate.
b. Interior light will illuminate on Glass Door Models. Light switch is on interior ceiling.
2. After the control preprogrammed time delay of up to 6 minutes, the compressor and evaporator fan(s) will start if the
control is calling for cooling.
a. Condenser fans may be already pre-programmed from the factory so at the start of every compressor cycle the
condenser fan(s) will reverse for 30 seconds to blow dirt off the condensing coil.
3. The control will cycle the compressor and also cycle evaporator fan(s) on and off determined by the Set-Point and
Differential temperatures.
a. The Set-Point is the adjustable preprogrammed temperature.
b. The Differential is the non adjustable preprogrammed temperature.
c. The control is designed to read and display a cabinet temperature
not a product temperature
.
This cabinet temperature may reflect the refrigeration cycle of the Set-Point and its Differential, or it may show an
average temperature.
The most accurate temperature on a cabinets operation is to verify the product temperature.
4. The control is preprogrammed to initiate defrost by interval.
a. At this time the “dEF” will appear on the display and compressor will turn off until a preprogrammed temperature or
duration is reached. During this time for freezers only, evaporator fan(s) will also turn off and the coil heater and drain tube
heaters will also be energized.
b. After the preprogrammed temperature or duration for defrost has been reached there may be a short delay for both the
compressor and evaporator fans to restart. At this time “dEF” may still appear on the display for a short time.
ELECTRONIC TEMPERATURE CONTROL GENERAL SEQUENCE OF OPERATION -
HEALTH SAFETY TIMER (HST) MODELS
t1 = Thermostat
t2 = Defrost
t3 = Display Temperature
HEALTH SAFETY TIMER
