Mars Century EarthPure HNW Series, Инструкция по установке, эксплуатации и обслуживанию

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Installation, Operation & Maintenance - HNW Series
Hot Water Generator
The HWG (Hot Water Generator) or desuperheater option
provides considerable operating cost savings by utilizing
excess heat energy from the heat pump to help satisfy
domestic hot water requirements. The HWG is active
throughout the year, providing virtually free hot water when
the heat pump operates in the cooling mode or hot water at
the COP of the heat pump during operation in the heating
mode.
Heat pumps equipped with the HWG option include a built-in
water to refrigerant heat exchanger that eliminates the need
to tie into the heat pump refrigerant circuit in the field. The
control circuit and HWG pump are also built in and factory
wired for residential equipment. Figure 3 shows a typical
example of HWG water piping connections on a unit with
built-in pump. This piping layout minimizes scaling potential.
Electric water heaters are recommended. If a gas, propane,
or oil water heater is used, a second preheat tank should
be considered (Figure 4). Also, if the electric water heater
has only a single center element, the dual tank system is
recommended to insure a usable entering water temperature
for the HWG.
Hot Outlet
to House
Powered
Water
Heater
Upper
element to
120 - 130°F
[49 - 54°C]
Lower
element to
100 - 110°F
[38 - 43°C]
Cold Inlet from
Domestic supply
Shut-off
Valve #4
Shut-off
Valve #1
Insulated water lines -
5/8” OD, 50 ft maximum (one way) meters
[16mm OD, 15 meters maximum]
Shut Off
Valve #2
Shut-off
Valve #3
In
Out
Typically a single tank of at least 52 gallons (235 liters) is used
to limit installation costs and space. However, a dual tank, as
shown in Figure 4, is the most efficient system, providing the
maximum storage and temperate source water to the HWG.
It is always advisable to use water softening equipment on
domestic water systems to reduce the scaling potential and
lengthen equipment life. In extreme water conditions, it may
be necessary to avoid the use of the HWG option since the
potential cost of frequent maintenance may offset or exceed
any savings.
HFC-410A systems inherently have a lower hot gas
temperature than R-22 systems because the equipment is
more efficient (i.e. less waste heat is available). It is possible
that energy could be transferred from the water heater to
the hot gas line instead of from the hot gas line to the water
heater during certain times of the year. To prevent this from
occurring, a temperature switch will deactivate the pump
at those conditions that typically occur in the cooling mode
with low entering water temperatures.
Figure 3: Typical HWG Installation
Insulated water lines - 5/8” OD, 50 ft maximum (one way)
[16mm OD, 15 meters maximum]
Upper element to 130°F [54°C]
(or owner preference)
Cold Inlet
Hot Outlet to
house
Powered
Water Heater
Cold Inlet from
Domestic supply
Hot Outlet
Unpowered
Water Heater
Field Supplied 3/4” brass nipple and “T”
Lower element to 120°F [49°C]
Shut-off
Valve #1
Shut-off
Valve #4
Shut-off
Valve #3
Shut Off
Valve #2
In
Out
Figure 4: HWG Double Tank Installation
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