Heat Controller HTD Heat Pump User Manual


 
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Installation, Operation & Maintenance HTV/HTD/HTH SERIES Heat Controller, Inc.
Preventive Maintenance
Water Coil Maintenance
(Direct ground water applications only) - If the system is installed
in an area with a known high mineral content (125 P.P.M. or
greater) in the water, it is best to establish a periodic maintenance
schedule with the owner so the coil can be checked regularly.
Consult the well water applications section of this manual for a
more detailed water coil material selection. Should periodic coil
cleaning be necessary, use standard coil cleaning procedures,
which are compatible with the heat exchanger material and
copper water lines. Generally, the more water owing through
the unit, the less chance for scaling. Therefore, 1.5 gpm per ton
[2.0 l/m per kW] is recommended as a minimum ow. Minimum
ow rate for entering water temperatures below 50°F [10°C] is 2.0
gpm per ton [2.6 l/m per kW].
Water Coil Maintenance
(All other water loop applications)
Generally water coil maintenance is not needed for closed loop
systems. However, if the piping is known to have high dirt or
debris content, it is best to establish a periodic maintenance
schedule with the owner so the water coil can be checked
regularly. Dirty installations are typically the result of deterioration
of iron or galvanized piping or components in the system.
Open cooling towers requiring heavy chemical treatment and
mineral buildup through water use can also contribute to higher
maintenance. Should periodic coil cleaning be necessary, use
standard coil cleaning procedures, which are compatible with both
the heat exchanger material and copper water lines. Generally,
the more water owing through the unit, the less chance for
scaling. However, ow rates over 3 gpm per ton (3.9 l/m per kW)
can produce water (or debris) velocities that can erode the heat
exchanger wall and ultimately produce leaks.
Hot Water Generator Coils
See water coil maintenance for ground water units. If the potable
water is hard or not chemically softened, the high temperatures
of the desuperheater will tend to scale even quicker than the
water coil and may need more frequent inspections. In areas with
extremely hard water, a HWG is not recommended.
Filters
Filters must be clean to obtain maximum performance. Filters
should be inspected every month under normal operating
conditions and be replaced when necessary. Units should never
be operated without a lter.
Washable, high ef ciency, electrostatic lters, when dirty, can
exhibit a very high pressure drop for the fan motor and reduce
air ow, resulting in poor performance. It is especially important
to provide consistent washing of these lters (in the opposite
direction of the normal air ow) once per month using a high
pressure wash similar to those found at self-serve car washes.
Condensate Drain
In areas where airborne bacteria may produce a “slimy”
substance in the drain pan, it may be necessary to treat the drain
pan chemically with an algaecide approximately every three
months to minimize the problem. The condensate pan may also
need to be cleaned periodically to insure indoor air quality. The
condensate drain can pick up lint and dirt, especially with dirty
lters. Inspect the drain twice a year to avoid the possibility of
plugging and eventual over ow.
Compressor
Conduct annual amperage checks to insure that amp draw is no
more than 10% greater than indicated on the serial plate data.
Fan Motors
All units have lubricated fan motors. Fan motors should never be
lubricated unless obvious, dry operation is suspected. Periodic
maintenance oiling is not recommended, as it will result in dirt
accumulating in the excess oil and cause eventual motor failure.
Conduct annual dry operation check and amperage check to
insure amp draw is no more than 10% greater than indicated on
serial plate data.
Air Coil
The air coil must be cleaned to obtain maximum performance.
Check once a year under normal operating conditions and, if
dirty, brush or vacuum clean. Care must be taken not to damage
the aluminum ns while cleaning. CAUTION: Fin edges are sharp.
Cabinet
Do not allow water to stay in contact with the cabinet for long
periods of time to prevent corrosion of the cabinet sheet metal.
Generally, vertical cabinets are set up from the oor a few inches
[7 - 8 cm] to prevent water from entering the cabinet. The cabinet
can be cleaned using a mild detergent.
Refrigerant System
To maintain sealed circuit integrity, do not install service gauges
unless unit operation appears abnormal. Reference the operating
charts for pressures and temperatures. Verify that air and water
ow rates are at proper levels before servicing the refrigerant
circuit.