Hussmann LPL, LPM, LPH Remote Unit Installation & Service Instructions.pdf

The LPL, LPM, and LPH remote units are designed for use with small refrigeration cabinets or walk-ins. They are available with hermetic and semi-hermetic compressors and come pre-wired and pre-piped. The units have a number of standard features, including an outdoor housing, compressor, condenser, condenser fans, low ambient fan thermostat, insulated receiver, crankcase heater, head pressure control valve, dual pressure control, liquid line switch, drier and sight glass, compressor shut-off switch, crankcase heater switch, desuperheater coil, and crankcase pressure regulator.

Optional features include spring-mounted compressors, vibrasorbers, vibration pads, defrost timers, temperature control for refrigeration systems, refrigerant line sets, electrical line sets, coated condensers, copper finned condensers, crankcase heater thermostats, and crankcase heater relays.

Upon receipt of the unit, inspect the crate for damage and make a note on the delivery ticket if it is damaged. Remove the shipping crate and examine the unit for concealed damage. If damage is found, contact the delivery carrier immediately and have them prepare an inspection report for filing a claim.

The unit should be located where it is level and easily accessible for service. Remove all shipping material when the unit is permanently located. Ensure there is an unobstructed airflow through the condenser for 1.5 feet in front of the unit and 6 inches over the top of the unit. If placing multiple units next to each other, they should be at least 3 feet apart.

When placing the unit on a roof, lift it by the base frame and use a spanner bar to prevent excess stress on the sheet metal parts. Under normal conditions, little maintenance is required, but the following housekeeping practices will ensure trouble-free operation: check the condenser fan motors, oil the fan motors periodically, set up a routine to clean the condenser, check the dual pressure control capillary tubes, and check the tubing and electrical lines for rubbing due to vibration.

When connecting piping, use top-quality refrigeration-grade tubing of recommended wall thickness, follow good piping practices, and, if applicable, the job's piping specifications. Brazing should be done carefully and properly, using clean, dehydrated, sealed refrigeration-grade copper tubing and silver alloy brazing material. Use dry nitrogen to prevent the internal formation of copper oxides and carbon. A pressure regulator must always be used with nitrogen cylinders.

When a leaking brazed joint is found, it should be pulled apart, cleaned, and inspected before re-brazing. Service valves must be UL-approved for a minimum of 410 psig working pressure. Long-radius elbows are recommended, and 45-degree elbows are not recommended. All piping must be supported to eliminate excessive line vibration, which can cause noise transmission, vibration transmission, line breakage, and other issues.