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WATER SUPPLY
(UNIT CONNECTED ON OPEN WATER CIRCUIT)
The source of water for heat pump operation is the responsibility of the owner and/or the installing
contractor. The heat pump must not function without water, and predetermined flow rates (l/s or
USGPM) must be maintained for the unit to operate at rated capacity. Since the water function is to
absorb heat from the refrigerant, the flow rate for each model varies with the entering water
temperature (EWT). Piping size to and from unit must match or exceed the inlet and outlet water
connection sizes on the heat pump.
WATER CONNECTIONS
If flexible hoses are used to make the water in/out connections to the unit, certain precautions must
be taken to ensure proper unit operation and avoid hose damage.
Never use a hose of a smaller inside diameter than that of the water connection sizes on the unit.
The hoses must be rated to match or exceed temperatures and pressures which occur during normal
operation of system (temperature between 4° C (40° F) and 43° C (110° F); and pressures up to
1380 kPa (200 PSI).
When hoses are connected they must not be subjected to any stress in tension, twisting or
kinking.
Hoses available as an accessory to the unit are provided with hexagonal surfaces on the fittings,
as are the water fittings on units. Use a properly sized wrench on the hexagonal surface to
tighten connections. Never use a wrench on the hose or sleeve that crimps the fitting into the
hose.
Do not over-tighten connections. Turn in the mating threads by hand or with a wrench until
snug, then tighten with a wrench beyond the point just enough to seal the joint (for tapered pipe
threads this would be an additional 1/2 to one full turn; for union or flare connections no more
than 1/4 of a turn).
Before pressurizing the system, closely inspect the hose and fittings to be sure there are no cuts,
abrasions, twists or kinks. Hoses must not be in contact with any sharp edge while in use. Hose
supplier will not take responsibility for hose leakage, failure or damage resulting from water
leaks.
SUPPLY DUCTING
Flanges around the blower opening are
intended for a flexible supply air duct
connection to unit. Be certain blower
wheel turns freely before making the duct
connection. Supply air ductwork must be
insulated with 25 or 38-mm thick (1" or 1
1/2") fiberglass, sealed at all joints and
must have an exterior vapour barrier. The air conditioner's life expectancy and efficient
performance are dependent on adequate airflow. For the higher limit of the external static pressures
range, the motor pulley must be adjusted until the motor amperage is below the rated motor
amperage (a blower motor draws more amperage if there is not enough static pressure.) The unit
pulleys are adjusted for low static; if installing in a high static environment, pulley must be
adjusted.
