Helmer Scientific i.Series
®
and Horizon Series
™
Freezer - Undercounter
Service and Maintenance Manual
360417/A
62
Horizon Series
12 Service
12.1 Refrigerant
Risk of fire or explosion. Flammable refrigerant used. To be repaired only by trained service personnel. DO NOT puncture
refrigerant tubing.
NOTICE
• Review all safety instructions prior to recharging refrigerant.
• Maintenance should only be performed by trained refrigeration technicians familiar with hydrocarbon refrigerants.
Table 14. Refrigerant Charge
Refrigerant
Initial Charge
R290
3.0 oz. (85 g)
12.2 Remove / Replace Unit Cooler Cover
The unit cooler cover must be removed when servicing the control probe, fan motor(s) or coil.
• If unit cooler cover is not removed as detailed in this procedure the drain port may be damaged. Improper drainage
may result in excessive icing and freezer's inability to maintain temperature.
• The condensate evaporator and water evaporation tray will be hot.
Unit cooler cover and drain port
Drain tube and heating element
Remove Unit Cooler Cover
1. Switch the AC power switch OFF. Switch the back-up battery switch OFF.
2. Remove the top drawer or shelf from the cabinet.
3. Cut the wire ties securing the drain line to the cabinet.
4. On the back of the unit, peel the putty back to expose the drain tube and drain heater.
5. Remove the wire ties securing the heater wires to the cabinet. Verify the heating element is cool.
6. From the rear of the unit, remove the drain heater from the drain tube.
7. Remove the drain tube in the back of the unit by pulling it downward.
8. Inside the cabinet, detach the section of the drain tube connected to the unit cooler drain spout by gently twisting to
separate, then pivot the drain tube upward and remove.
9. Using a 5/16” socket wrench, remove the four screws securing the unit cooler cover to the top of the cabinet while
supporting the cover with one hand to prevent it from dropping.
10. Carefully lower the unit cooler cover to avoid damage to the fan wiring.
Label
Description
A
Unit cooler cover
B
Drain port
C
Heating element
D
Heater wires
E
Drain tube
A
B
E
D
C
