Heatcraft Refrigeration Products H-IM-82B installation and operation guide Freezers

Medium and Large Cabinet Freezers

	Service Information			3.	The temperature/defrost control energizes the
					compressor contactor, starting the compressor and
All		units are designed for maximum durability, reliability and
					condenser fan(s).
simplicity.			comes to you ready for operation, fully charged and
				4.	Freezer evaporator fans will be energized by the
with all controls preset at the factory. The following information is

provided as an aid in the event that service is required.	temperature/defrost control when the coil temperature
	reaches 35°F or fan delay time has elapsed.

2.Freezers

Maintenance

The evaporator section of a system should be checked at least once for proper defrosting because the amount and pattern of frosting can vary greatly. The frost build-up is dependent on the temperature of the room, the type of product being stored, how often new product is brought into the room and percentage of time the door to the room is open. It may be necessary to periodically change the number of defrost cycles or adjust the duration of defrost.

System Standard Maintenance Guidelines

After first year of operation and under normal usage, maintenance should cover the following items at least once every six months:

1.Check and tighten ALL electrical connections.

2.Check all wiring and insulators.

3.Check contactors for proper operation and for worn contact points.

4.Check all fan motors. Tighten motor mount bolts/ nuts and tighten fan set screws.

5.Clean the condenser coil surface.

6.Check the operation of the control system. Make certain all safety controls are operating properly.

7.Check that all defrost controls are functioning properly.

8.Clean the evaporator coil surface.

9.Clean the drain pan and check the drain pan and drain line for proper drainage.

Refrigeration Sequence of Operation

1.Power is provided to the temperature control, compressor contactor and cooler evaporator fans.

2.The temperature controller closes and energizes the compressor contactor, starting the compressor, evaporator and condenser fan(s).

3.When the system reaches the desired box temperature, the temperature control will de-energize the compressor contactor. Evaporator fans will continue to operate at this point.

4.When the fixture temperature rises above the set point and minimum off-time has elapsed, the temperature control will close and re-energize the compressor contactor.

Electric Defrost Sequence of Operation for Freezers

1.During normal operation, at the preset time intervals, the temperature/defrost control will de-energize the

compressor contactor and evaporator fans and energize the defrost heaters. These functions are controlled through relays on the controller.

2.When the coil has defrosted fully and has reached the preset coil temperature (as sensed by the coil temperature sensor) the defrost heater de-energizes and the fan delay and drip sequences begin.

Freezer Defrost Control -

Medium & Large Cabinet

freezer units come factory equipped with an electronic temperature/defrost control. There are 2 different models of electronic control used and it is important to determine which one is present on your unit before altering any factory settings. Please refer to the picture of the controller display on this page to determine the model used. Instructions for any necessary reprogramming are included in this manual on pages 8-10.

Dixell Electronic Controller

The Dixell XR-60CX and the Dixell XR-60C are fully configurable electronic refrigeration controllers. All parameter values are reprogrammable and are stored in the non-volatile memory.

The controllers use two levels of programming that can be accessed through the keypad. The first level is the user level. It gives access to six settings; temp. differential, defrost cycle intervals, defrost termination temperature, draining time, defrost fan delay, and fan stop temperature.

The second level is the service level. It allows access to all other parameters. It is recommended that changes in this level be made only by a qualified technician.

Front Panel Commands

XR-60CX Controller XR-60C Controller

Use of LEDS

Each LED function is described in the following table.

LED	LED MODE	FUNCTION
	ON	Compressor enabled
	Flashing	-Programming Phase (flashing	with )
		- Anti-short cycle delay enabled
	ON	Defrost enabled
	Flashing	- Programming Phase (flashing	with )
		- Drip time in progress
	ON	Fans enabled
	Flashing	Fans delay after defrost in progress
		(60CX only)
	ON	A temperature alarm occurred