Evaporator Coil - Observe fan compartment Caution note at the beginning of the Service section.
Remove dirt and debris from evaporator coil as required by condition. Clean coil with a stiff brush, vacuum cleaner or compressed air. Use a fin comb of the correct tooth spacing (Refer to Tables 1A/B/C/2A/B/C for coil fins/inch) when straightening mashed or bent coil fins.
Water Regulating Valve
PREPARATION FOR OPERATION.
1.Open the water regulating valve inlet and outlet isolation valves.
2.Close the water regulating valve bypass valve.
ADJUSTMENT
NOTE: Adjustments to the water regulating valve must be made slowly, allowing ample time for response and stabilization.
1.The compressor discharge pressure is controlled by the water regulating valve and may be monitored by observing liquid line pressure.
2.Install a calibrated gauge at the liquid line service port. FOR 90MA: Operating liquid line range for
FOR 90MU : Operating liquid line range for
If pressure reading is above operating range, rotate the square head adjusting screw clockwise; this will decrease spring tension, increase water flow and decrease pressure.
3.Only the water regulating valve opening point is adjustable. The closing point is 3 to 7 psig below the opening point and is
Condenser - Condensers may require cleaning of water- deposited scale.
CAUTION
Follow all Safety codes. Wear safety glasses and rubber gloves when using inhibited hydrochloric acid solution.
Clean condensers with an inhibited hydrochloric acid solution. The acid can stain hands and clothing, attack concrete and, without inhibitor, can attack 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 effective if applied for a longer period.
FIGURE 9 - GRAVITY FLOW METHOD
GRAVITY FLOW METHOD (Figure. 9) -
1.Disconnect condenser piping at unit, including isolation valves and water regulating valve.
2.Fill condenser as shown in figure 9. Follow acid manufacturer's instructions. When condenser is full, allow solution to remain overnight
3.Drain condenser and flush with clean water.
FORCED CIRCULATION METHOD (Figure. 10) -
1.Disconnect condenser piping at unit, including isolation valves and water regulating valve.
2.Fill system as shown in figure 10. Follow acid manufacturer's instructions. Fully open vent pipe when filling system. The vent may be closed when system is full and pump is operating.
3.Regulate flow to condenser with a supply line valve. If pump is a
4.Drain condenser and flush with clean water.
FIGURE 10 - FORCED CIRCULATION METHOD
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations
Printed in U.S.A. | Pg 14 | |
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