Face Seal Replacement and Adjustment
To replace the face seals, the cassette assembly must be
removed from the unit. Disconnect the service connector
to the drive motor of the enthalpy wheel cassette. Remove
the cassette from the unit and stand the assembly up
on the floor or roof. Remove the screws holding the face
seals (#5, Figure 9). Replace the two seals (supply and ex-
haust sides), cutting to length as required. Adjust the seals
in the slots so that the brush just touches the face of the
wheel. Complete the installation by reversing the above
procedure.
Enthalpy Wheel Drive Belt Replacement
and Tensioning Adjustment
The enthalpy wheel drive belt can be tightened by sliding
the cassette assembly only part way out of the unit. Dis-
connect the service connector to the drive motor of the
enthalpy wheel cassette. Slide the cassette assembly out
of the unit enough to access the drive motor. See
for belt tensioning and replacement instructions. The
multi-link belt is factory set for proper tension but should it
need a tension adjustment, simply remove one of the link
sections and re-install the belt.
Testing and Replacement of the Damper Actuator
After disconnecting the power from the unit, determine if
the actuator is defective. Disconnect the 24V power source.
Connect the actuator directly to a 24V power source with
an appropriate cable. If the damper operates correctly, the
problem is either in the wiring connections or main circuit
board.
If the actuator does not work, it must be replaced. Loosen
the nuts on the jack shaft clamp and remove the actua-
tor. Tighten the clamp on the damper jack shaft. Test for
proper operation.
WARNING
Disconnect the main power switch to the unit before per-
forming service and maintenance procedures.
CAUTION
When handling the enthalpy wheel, ensure not to dam-
age the face of the wheel.
CAUTION
When handling the enthalpy wheel, ensure not to dam-
age the face of the wheel.
VCES-VHC-IOM-1F – VHC-36, -42 & -50
23
