INSTALLATION AND OPERATION MANUAL
PAC HEAT RECOVERY WATER HEATER
Refrigeration Connections
Mueller Fre-Heaters are shipped with a dry nitrogen holding charge that
must be removed from the Fre-Heater piping before installation of
refrigerant piping.
Good refrigeration practices must be used while installing the Fre-Heater.
These practices are of common knowledge to the experienced refrigeration
serviceman, and only a certified, experienced refrigeration serviceman should
undertake the refrigeration connection portion of a Fre-Heater installation.
Inlet and outlet stubs are copper tube for Freon applications and stainless
steel male pipe thread for ammonia applications. The sizes of refrigeration
connections for various PAC Fre-Heaters are shown in Table 1.
On runs 8 metres or less, refrigeration lines to and from the Fre-Heater
should be the same size as the compressor discharge line.
Avoid long runs whenever possible. However, if necessary to have runs of
more than 8 metres, the lines should be upsized by one tube size. Should
there be any question about refrigeration line sizing, the equipment
manufacturer’s recommendation should be followed.
In most instances, refrigeration line runs of over 16 metres should not be
used. If they are, particular care must be taken to avoid oil traps and excessive
pressure drop in the lines.
The refrigeration lines going to and from PAC
Fre-Heaters could reach
temperatures of 150°C. The refrigeration lines must be insulated to prevent a
burn hazard for personal injury or combustible substances. The insulation will
also add to the efficient operation of the Fre-Heater.
If in making tubing connections, it is necessary to cut openings into the
air-conditioning or refrigeration cabinet, the following must be observed
and provided for. Particular care must be taken if the equipment is located
outdoors.
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Integrity and rain tightness of the cabinet must be maintained.
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Do not cut into a control box or enclosure containing live
mechanical parts or electrical wiring. Make openings below any
enclosures containing live mechanical parts or electrical wiring.
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Tubing must be protected against mechanical damage by the
cabinet. The use of protective bushings is recommended.
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Tubing connections must be made by means of high-
temperature soldering or brazing.
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