produce water (or debris) velocities that can erode the heat ex- changer wall and ultimately produce leaks.
Proper water treatment can minimize tube fouling and pitting. If such conditions are anticipated, water treatment anal- ysis is recommended. Refer to the Carrier System Design Man- ual, Part 5, for general water conditioning information.
CAUTION
Follow all safety codes. Wear safety glasses and rubber gloves when using inhibited hydrochloric acid solution. Observe and follow acid manufacturer’s instructions.
Clean condensers with an inhibited hydrochloric acid solu- tion. The acid can stain hands and clothing, damage concrete, and, without inhibitor, damage steel. Cover surroundings to guard against splashing. Vapors from vent pipe are not harmful, but take care to prevent liquid from being carried over by the gases.
Warm solution acts faster, but cold solution is just as effec- tive if applied for a longer period.
GRAVITY FLOW METHOD — Do not add solution faster than vent can exhaust the generated gases.
When condenser is full, allow solution to remain overnight, then drain condenser and flush with clean water. Follow acid manufacturer’s instructions. See Fig. 37.
FILL CONDENSER WITH |
| |
CLEANING SOLUTION. DO | PAIL | |
NOT ADD SOLUTION | ||
| ||
MORE RAPIDLY THAN |
| |
VENT CAN EXHAUST |
| |
GASES CAUSED BY | FUNNEL | |
CHEMICAL ACTION. | ||
| 1” | |
| PIPE | |
VENT |
| |
PIPE | 5’ APPROX | |
|
3’ TO 4’
CONDENSER
PAIL
Fig. 37 — Gravity Flow Method
FORCED CIRCULATION METHOD — Fully open vent pipe when filling condenser. The vent may be closed when condenser is full and pump is operating. See Fig. 38.
Regulate flow to condenser with a supply line valve. If pump is a nonoverloading type, the valve may be fully closed while pump is running.
For average scale deposit, allow solution to remain in con- denser overnight. For heavy scale deposit, allow 24 hours. Drain condenser and flush with clean water. Follow acid manu- facturer’s instructions.
PUMP | PRIMING | GAS VENT |
| CONN. | GLOBE |
|
| |
|
| VALVES |
SUCTION |
|
|
PUMP |
| SUPPLY |
|
| |
SUPPORT |
| 1” PIPE |
|
| |
|
| CONDENSER |
TANK |
| REMOVE WATER |
|
| |
|
| REGULATING VALVE |
FINE MESH |
| RETURN |
SCREEN |
|
|
Fig. 38 — Forced Circulation Method
Condensate Pans — Check condensate drain pans for algae growth every three months. If algae growth is apparent, consult a water treatment specialist for proper chemical treat- ment. The application of an algaecide every three months will typically eliminate algae problems in most locations. Check condensate hose for leaks and blockage and correct any problems.
Blower Motors — All units have lubricated fan motors.
BLOWER MOTORS SHOULD NEVER BE LUBRICATED UNLESS OBVIOUS, DRY OPERATION IS SUSPECTED. Periodic maintenance oiling is not recommended because it will result in dirt accumulating on excess oil and cause eventu- al motor failure. Conduct annual dry operation check and am- perage check to ensure amp draw is no more than 10% greater than that indicated by serial plate data.
Compressor — Conduct an amperage check annually on the compressor and fan motor. Amperage draw should not exceed normal full load amps. Maintain a log of amperage to detect deterioration prior to component failure.
Safety Control Reset — The 50PEC heat pumps are furnished with
The contacts of the
The machine must be reset manually. Reset is accomplished by pressing the STOP button and then pushing either HI HEAT, LOW HEAT, HI COOL or LO COOL to restart the unit in the desired mode of operation. (The 50PEC unit can also be reset by opening and closing the supply power disconnect switch.)
IMPORTANT: If the unit must be reset more than twice, check the unit for a dirty filter, abnormal entering water temperature, inadequate or excessive water flow, and inter- nal malfunctions. If the unit continues to cut out, contact a trained service technician.
WARNING
When replacing the compressor contactor or lockout relay in a unit with electromechanical controls, use only Carrier factory authorized parts. Substitution of other components may result in an inoperative safety circuit and may cause a hazardous condition.
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