Open Loop (Well System Applications); Water Connections; Figure 27 Piping Diagram - Bard QW Series Installation Instructions Manual

WATER CONNECTIONS

It is very important that an adequate supply of clean,
noncorrosive water at the proper pressure be provided
before the installation is made. Insufficient water,
in the heating mode for example, will cause the low
pressure switch to trip, shutting down the heat pump.
In assessing the capacity of the water system, it is
advisable that the complete water system be evaluated
to prevent possible lack of water or water pressure
at various household fixtures whenever the heat
pump turns on. All plumbing to and from the unit
is to be installed in accordance with local plumbing
codes. The use of plastic pipe, where permissible,
is recommended to prevent electrolytic corrosion
of the water pipe. Because of the relatively cold
temperatures encountered with well water, it is strongly
recommended that the water lines connecting the unit
be insulated to prevent water droplets form condensing
on the pipe surface.
Refer to piping, Figure 27. Slow closing Solenoid
Valve (6) with a 24V coil provides on/off control of the
water flow to the unit. Refer to the wiring diagram for
correct hookup of the valve solenoid coil.
Constant Flow Valve (7) provides correct flow of water
to the unit regardless of variations in water pressure.
Observe the water flow direction indicated by the
arrow on the side of the valve body. Table 7 is a table
showing the flow rate of each valve. Two constant flow
rate valves may be installed in parallel to increase the
flow. For example, when a 8603-007 (6 GPM) and
8603-011 (5 GPM) are installed in parallel the total
flow will be 11 GPM.
Figure 27
Piping Diagram
10
11
6
(Well System Applications)
TABLE 7
Constant Flow Valves
Min. Available
Part No.
Pressure PSIG
CFV-5 15 
CFV-6
15 
CFV-7
15 
CFV-9 15 

The pressure drop through the constant flow valve will
vary depending on the available pressure ahead of the
valve. Unless minimum of 15 psig is available
immediately ahead of the valve, no water will flow.
Strainer (5) installed upstream of constant flow valve
(7) to collect foreign material which would clog the flow
valve orifice.
Figure 26 shows the use of shutoff valves (9 and 11),
on the in and out water lines to permit isolation of the
unit from the plumbing system should future service
work require this. Globe valves should not be used as
shutoff valves because of the excessive pressure drop
inherent in the valve design. Instead use gate or ball
valves as shut-offs so as to minimize pressure drop.
Drain cocks (8 and 10) and tees have been included to
permit acid cleaning the refrigerant-to-water coil should
such cleaning be required. See WATER CORROSION
section.
Drain cock (12) provides access to the system to check
water flow through the constant flow valve to ensure
adequate water flow through the unit. A water meter is
used to check the water flow rate.
8
9
7
12
MIS-2749
OPEN LOOP
Flow Rate GPM
5
6
7
9
Manual 2100-577C
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