21
KHF - SERIES A FAN COIL UNITS
INSTALLATION, OPERATION, AND MAINTENANCE MANUAL
COIL
Coils may be cleaned in place by removing the motor/ blower
assemblies and brushing the entering air face between fins
with a soft brush parallel to fins. Do not brush perpendicular
to fin orientation as damage may occur. Brushing should be
followed by cleaning with a vacuum cleaner. If a compressed
air source is available, the coil may also be cleaned by
blowing air through the coil fins from the leaving air face.
Vacuuming should again follow this. Units provided with the
proper type of air filters, replaced regularly, may require
periodic coil cleaning.
ELECTRIC RESISTANCE HEATER ASSEMBLY
Electric resistance heaters typically require no normal
periodic maintenance when unit air filters are changed
properly. Other conditions and equipment may affect the
operation and service life in the system. The two most
important operating conditions for an electric heater are
proper airflow and proper supply voltage. High supply
voltage and/or poorly distributed or insufficient airflow
over the element will result in element overheating. This
condition may result in the heater cycling on the high limit
thermal cutout. Open wire type heaters provided have an
automatic reset switch with a back-up high limit thermal
switch. Automatic reset switches are as the name implies;
they reset automatically after the heater has cooled down.
The high limit thermal cutout device is a manual reset safety
device. With proper unit application and during normal
operation, the high limit thermal cutout will not operate.
This device only operates when some problem exists. ANY
condition that causes high limit cutout MUST be corrected
immediately. Once the high limit trips, it may be reset once
the unit has cooled down. Refer to troubleshooting section
for high limit reset instructions. High supply voltage also
causes excessive amperage draw and may result in tripping
of the circuit breaker or blowing of the fuses on the incoming
power supply.
ELECTRICAL WIRING & CONTROLS
The electrical operation of each unit is determined by the
components and wiring of the unit and may vary from unit
to unit. Consult the wiring diagram for the actual type and
number of controls provided on each unit. The integrity of
all electrical connections should be verified at least twice
during the first year of operation. Afterwards, all controls
should be inspected regularly for proper operation. Some
components may experience erratic operation or failure due
to age. Wall thermostats may also become clogged with dust
and lint and should be periodically inspected and cleaned to
provide reliable operation.
When replacing any components such as fuses, contactors, or
relays, use only the exact type, size, and voltage component
as furnished from the factory. Any deviation without factory
authorization could result in personnel injury or damage
to the unit and will void all factory warranties. All repair
work should be done in such a manner as to maintain
the equipment in compliance with governing codes and
ordinances or testing agency listings.
More specific information regarding the use and operating
characteristics of the standard controls offered by this
manufacturer is contained in other manuals.
VALVES & PIPING
No formal maintenance is required on the valve package
components most commonly used with fan coil units other
than a visual inspection for possible leaks in the course
of other normal periodic maintenance. In the event that
a valve should need replacement, the same precautions
taken during the initial installation to protect the valve
package from excessive heat should also be used during
replacement. If a strainer is ordered with the unit the strainer
must be cleaned periodically along with other scheduled
maintenance. In some cases, the valve actuator may fail and
usually can be replaced without removing valve body from
piping.
DRAIN
The drain should be checked before initial start-up and at
the beginning of each cooling season to assure that the lines
are clear. If it is clogged, steps should be taken to clear the
debris so that condensate will flow easily.
Periodic checks of the drain should be made during the
cooling season to maintain a free flowing condensate. Should
the growth of algae and/or bacteria be a concern, consult
an air conditioning and refrigeration supply organization
familiar with local conditions for chemicals available to
control these agents. If cleaners are used, they should be
compatible with the materials of construction for the coil,
drain pan, and condensate pump (if applicable).
To Next Page
Loading...
Need help?
General
