Comfort-Aire HBH Series 1/2 to 5 Ton - Manual (Page 39)

Heat Controller, Inc. HBH/V COMPACT IOM Instructions
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 flowing through the unit, the less chance
for scaling. Therefore, 1.5 gpm per ton [1.6 l/m per kW]
is recommended as a minimum flow. Minimum flow rate
for entering water temperatures below 50°F [10°C] is 2.0
gpm per ton [2.2 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 flowing
through the unit, the less chance for scaling. However,
flow 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.
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 filter.
Washable, high efficiency, electrostatic filters, when dirty,
can exhibit a very high pressure drop for the fan motor
and reduce air flow, resulting in poor performance. It is
especially important to provide consistent washing of
these filters (in the opposite direction of the normal air
flow) 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 filters. Inspect
the drain twice a year to avoid the possibility of plugging
and eventual overflow.
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 fins 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 floor 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 flow rates are at
proper levels before servicing the refrigerant circuit.