Kysor/Warren 6RLG3, Installation & Operation Manual

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Hot Gas Defrost Models
On hot gas defrost models (optional for parallel compressor operation only) hot gas is routed
through the suction line and evaporator coil. It exits the coil through a by-pass around the
expansion valve and heat exchanger to return to the liquid line where the condensed liquid is use
to feed the other cases on the same parallel unit. The case fans continue to operate during defrost
to warm up the drain pan and air ducts. The defrost cycle is time initiated and should be
temperature terminated. Recommended hot gas defrost is four (4) per 24 hours with a 20 minute
fail-safe.
Operation Checklist
In addition to the usual standard practices for installing your case, please pay particular attention
to the following:
1. Have all cracks been sealed using commercially available, silicone caulking compound?
2. Has refrigeration line entry been caulked inside and out to seal off the two air bands?
3. Are both upper and lower fans running? Check all plugs to ensure the plugs are tight and
are completely engaged.
4. Is the defrost control set for the proper setting as recommended by the case defrost
recommended settings provided in Chapter 6, Operation?
5. Measure the amperage on all three legs on the three phased defrost receptacle during the
defrost cycle. The amperage used on each leg should be equal, +/-10% (balance the load
voltage on all three legs).
6. Are all other connections, including flare connections, tight?
OPERATION
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