43
EKW FX10 INSTALLATION MANUAL
Preventive Maintenance
Keep all air out of the water lines. An open loop system should be checked to ensure that the well head is not allowing
1.
air to infiltrate the water line. Lines should always be airtight.
Keep the system under pressure at all times. In open loop systems, it is recommended that a water control valve be
2.
placed in the discharge line to prevent loss of pressure during off cycles. Closed loop systems must have a positive
static pressure.
note
: If the installation is performed in an area with a known high mineral content in the water, it is best to establish a peri-
odic maintenance schedule to check the water-to-refrigerant heat exchanger on a regular basis. Should periodic cleaning
be necessary, use standard cleaning procedures which are compatible with either the cupronickel or copper water lines.
Generally, the more water flowing through the unit, the less chance there is for scaling. Low flow rates produce higher tem
-
peratures through the coil. To avoid excessive pressure drop and the possibility of copper erosion, do not exceed flow rate
as shown on the specification sheets for each unit.
Cleaning Procedure
Close the inlet and outlet water valves to isolate the heat pump from the well system, water heater or loop pumps.
1.
Disconnect piping and remove solenoid valve, pumps, etc, from the inlet and outlet connections on the heat pump.
2.
Connect plastic hoses from the circulating pump* to the outlet of the water-to-refrigerant heat exchanger to be de-limed
3.
(refer to Figure 16).
Connect a plastic hose from the circulating pump inlet to the bottom of a plastic twenty (20) liter pail (refer to Figure 16).
4.
Connect a plastic hose from the inlet line of the water-to-refrigerant heat exchanger to the plastic pail. Secure tightly to
5.
ensure that circulating solution does not spill (refer to Figure 16).
Partially fill the plastic pail with clear water (about two-thirds full) and prime the circulating pump. Circulate until lines
6.
are full.
Start the circulating pump and slowly add a commercial scale remover** to the water as recommended by the scale
7.
remover manufacturer’s directions.
Be sure the pump circulation is opposite to the normal water flow through the water-to-refrigerant heat exchanger.
8.
Maintain re-circulation until all scale and other material has been dissolved and flushed from the heat exchanger.
9.
Upon completion of the procedure. Safely dispose of the solution.
10.
Rinse the pump and plastic pail. Refill with clear water.
11.
Start the pump circulation and flush the system until all acid residue has been removed from the system. Refill the
12.
plastic pail until only clear water is circulated.
Turn off the circulating pump and disconnect all hoses and fittings.
13.
Replace solenoid valves, pumps, hoses and other devices in their original locations. On closed loop systems, be sure
14.
to purge between the flow center and unit to avoid getting air into the loop.
Put the heat pump back into operation. Check for proper operating temperature.
15.
WARning: this process involves a
caustic solution and may be harmful
to people and animals. Wear protective
equipment (glasses, rubber gloves,
apron, etc.)
notes:
*Virginia Chemical Co. makes a Pump model H460.
* W.W. Granger Co. sells a Pump #2P-017 made by Little Giant.
**Virginia Chemical Co. makes a liquid ice machine cleaner which should be used on water-to-refrigerant heat exchangers
serving a domestic hot water system. Calci-Solve by NYCO is available for use on other heat exchangers
Five-gallon Bucket
Pump
Figure 16: Cleaning Connections
