Aquacal T65 Heat Pump User Manual


 
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TXV Stuck Open:
Head pressure will be slightly to moderately low;
Suction pressure will be slightly high to very high;
Amperage (not a reliable indicator of this condition);
Liquid Sub-Cooling will be lower than normal;
Superheat will be minimal or nonexistent;
Suction line, and possibly a large portion of compressor, will be very cold and possibly “sweating”.
Explanation: Refrigerant is flowing through the system too quickly; enough heat cannot be added in the
evaporator to boil off all the liquid refrigerant. The main effect is to flood the suction line and compressor
with liquid refrigerant. The primary indicator of this condition is little or no suction line superheat. Also, as
the TXV is not holding back the required amount of refrigerant, there may be flash gas (high-pressure
vapor) present in the liquid line; this is indicated by reduced liquid sub-cooling.
Insufficient Condenser Water Flow:
Head pressure will moderately high to very high;
Suction pressure my be normal to slightly high;
Amperage will be higher than normal;
Liquid Sub-Cooling will be absent; the liquid line will be very warm or even hot to touch. When combined
with high condenser water DT (see next bullet item), this condition is a prime indicator of insufficient
condenser water flow;
Condenser entering-leaving water temperature difference (water DT) will be higher than normal… This
condition is a prime indicator of insufficient condenser water flow;
Superheat will be high-normal to high.
Explanation: Heat is not being removed in the condenser in quantities sufficient to produce appreciable
amounts of liquid refrigerant. With no liquid seal occurring in the condenser, the liquid line–in essence–
becomes an extended discharge line. Keys to diagnosis: very warm to hot liquid line, and a high condenser
water Delta-T.
Placement of Heater
Every indoor installation is unique, therefore, there are no specific guidelines for this type of installation. For
assistance, please contact AquaCal’s Engineering or Technical department at (800) 786-7751; they will assist
you with your specific needs.
Outdoor Installation
Service and Operational Clearances:
Refer to recommended clearance drawings following this section. Allow 24" clearance between the heat
collection surfaces and walls, fences, shrubs, or other objects. The heat pump requires large volumes of air
moving over the heat collector.
Allow 5 feet of vertical clearance between the top of the heat pump and any roof overhang or
other obstruction. This clearance prevents cold discharge air from recirculating back into the evaporator
coils (recirculation would reduce the overall performance of the heat Pump).
Provide at least 30” open area in front of the main access panel. The electrical panel will need to
be accessed during installation and service, so avoid any plumbing obstructions that will restrict
easy access.
INSTALLATION
Indoor Installation
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