4
Marvair Classic AVHA Heat Pump I&O Manual
08/2018 Rev. 2
TO CLEAN FRESH AIR INTAKE FILTER:
A. Follow steps A and B at left
“TO CHANGE SYSTEM FILTER”.
B. Gently pull out the filter from the
bottom.
C. Wash the filter with water.
D. Reinstall the filter, by sliding it into the
retaining rail.
E. Replace the access door and turn the
power on to the unit.
2. Keep the outdoor coil clean. Wash it down with a garden
hose if necessary.
BE SURE THE UNIT DISCONNECT IS IN THE “OFF”
POSITION AND THAT ALL ELECTRICAL POWER TO
THE UNIT IS TURNED OFF BEFORE CLEANING THE
SYSTEM.
3. Since the heat pump is located outdoors, it is exposed to
all weather elements. Treat it with a good automobile paste
wax twice a year (in the spring and fall).
Check with your contractor if you have any questions regarding
the maintenance or operation of your unit.
INSTALLATION (A: CODES)
The installer SHALL comply with all local, state, and federal
codes and/or regulations pertaining to this type of equipment
and its installation. Such codes and/or regulations should take
precedence over any recommendations contained herein.
Installations SHALL be made in accordance with the National
Electrical Code, local codes, and recommendations made by
the National Board of Fire Underwriters.
INSTALLATION (B: UNIT SITE SELECTION)
1. To eliminate noise from being transmitted into noise
sensitive areas, the unit should NOT be installed on walls
adjoining bedrooms, sleeping quarters, or adjacent to
windows.
2. Locating the unit as close as possible to the main duct
system or area to be conditioned, will prevent lengthy duct
runs and unnecessary thermal and air-pressure losses.
3. The clearance to combustibles is 0” on all sides, and 1/4”
for the first three (3) feet of supply duct.
4. The condenser air inlets (left, right and bottom inlets)
SHALL be located at least 8” away from walls or other
obstructions for unrestricted airflow.
5. The condenser air outlet should be located at least 6’
away from any obstructions to prevent recirculation of
condenser air.
6. Bottom of the unit SHALL be located at least 12” away from
the ground or other obstructions for unrestricted airflow.
7. Service clearance is 28” from the electrical box access
panel located on the front of the unit and 28” from the
center, upper, and lower front access panels.
8. The wall selected for unit installation MUST be able to or
be made to safely support the weight of the unit.
9. Do NOT locate where heat, lint or exhaust fumes will be
discharged on the unit (as from dryer vents).
INSTALLATION (C: UNIT PREPARATION)
1. AVHA model units have top rain flashing built onto
the unit. The bottom-mounting flange for all models is
shipped separately and in place. (Refer to “Section J. Unit
Installation” for the recommended use of the bottom flange.)
2. Electrical entrances are located on the right side and left
side of all AVHA units. Refer to “Section H. Electrical Hook-
up” for details.
3. Bend the lids of return and supply opening to form a return
and supply air collars and install air gaskets.
4. The supply and return air ducts should be checked to be
sure they:
e. Match the openings on the unit to be installed.
f. Have the same distance between them vertically as
the openings on the unit to be installed.
5. Return and supply grilles must be used when the return
and supply are not ducted. When a supply grille is used
in the installation, the louver spacing must be no greater
than 5/8 inch.
6. If the factory-installed filter is used on your installation,
access to the filter is made through the center panel on
the front of the unit.
IF A REMOTE FILTER IS USED, SUCH AS A FILTER
GRILLE, THE FACTORY-INSTALLED FILTER MUST BE
REMOVED AND DISCARDED.
INSTALLATION (D: DUCTWORK)
1. Properly-sized duct systems are critical for satisfactory
operation of any air conditioning system. All ductwork
MUST be correctly sized for the design air flow requirement
of the equipment.
2. The recommended operation duct static is to deduct 0.07”
W.C. for any size of heater 5 kW to 20 kW on factory or
field-installed heaters.
3. Ductwork routed through wall cavities, as well as any duct
not in conditioned space, MUST be insulated. Supply
ducting routed through exterior walls MUST be insulated
with 1” insulation to the back of the unit.
4. Supply and return air ducts should be flush with the exterior
wall and sized to fit over the unit duct collars in order to
compress the collar air gasket.
5. If supply duct is flashed to the exterior of a building
constructed with combustible material, the flashing MUST
be insulated in order to maintain the required clearances
to combustible materials. Required clearance is 1/4” for
the first three (3) feet of supply duct.
INSTALLATION (E: FILTERS)
1. One-inch disposable filters are supplied standard in each
unit. Two-inch disposable filters can also be used and
are available as an option. The filter rack is adjustable
to accommodate 2” filters. The filter rack on this series is
adapted by removing the 1” filter brackets. Refer to the
Maintenance section for the procedures for changing the
filters.
2. If a filter grille is used in the installation, the filter should be
properly sized to allow a maximum velocity of 400 FPM.
WHEN A FILTER IS USED, THE FACTORY-INSTALLED
FILTER MUST BE REMOVED.
