12
HIGH EFFICIENCY DIRECT VENT FURNACES
SERVICING YOUR HEATER
All servicing activities must be carried out by a qualified
service technician or a service agency. The home owner
may not service the furnace. The home owner must read
this section to be informed of the periodic maintenance and
checks the required. All servicing (except on vent system)
must be carried out with the external casing removed.
After any servicing, the external casing must be reinstalled
properly.
CHECKING AND ADJUSTING THE
GAS MANIFOLD PRESSURE
The furnace comes set from the factory at the correct HI
and LO gas manifold pressures as shown in “Technical Data”.
It is recommended to check the pressures periodically
(minimum once a year). If adjustment is required, this can
be done by adjusting screws C and D.
Figure 8
A test gauge
must be connected as explained in “Checking the Gas
Manifold Pressure”.
PROCEED AS FOLLOWS:
1. Place the unit on and in the HI mode (knob in HI position).
2. Adjust the HI pressure by turning the screw C
(pressure regulator) to the value given in “Technical
Data”. Turn clockwise to increase the pressure, turn
counterclockwise to decrease it.
3. Turn the control knob clockwise until the gas control
switches to LO mode. The position in which this occurs
depends on the actual room temperature.
4. Loosen screw D until the correct value for the LO
pressure is achieved. Turn clockwise to decrease the
pressure, turn counterclockwise to increase it.
5. Switch the unit from LO to HI mode to check that both
the HI and LO pressures are correct. A tolerance of plus
or minus 0.1-inches w.c. on the pressure value is
acceptable. Readjust if needed.
6. Disconnect the test gauge and tighten firmly the
screw of the gauge connection, then check for gas
leaks from it.
The HI and LO pressures must be adjusted in the way
explained above. Never try to adjust them independently
from each other.
CHECKING, REMOVING AND REASSEMBLING OF THE
VENT AIR INTAKE SYSTEM
It is essential that the vent air intake system is examined
periodically (minimum once a year) to verify it is clean from
dust and deposits of solid materials such as leaves or nests.
The vent air intake system is checked from outside. Proceed
as follows:
1. Remove the vent cap by removing the three outer
screws.
Figure 7
2. Remove the inner flue pipe. Do not use tools; the pipe
can be extracted by hand.
3. Remove dust and deposits from the vent cap and flue
pipes. Deposits in the air pipe must be taken outside. Do
not push them inside the furnace. The outer air pipe may
not be removed from outside.
4. Reinstall the flue pipe from outside. Do not use glue
or sealants.
5. Reinstall the vent cap on the flue pipe. Do not use glue
or sealants. Tighten the three outer screws.
LUBRICATION OF MOVING PARTS
This furnace does not require lubrication. Do not try to
lubricate any part of the furnace such as motors bearings,
keys, knobs, screws, etc.
FLAME VISUAL CHECK
Correct and proper operation of the burner may be
checked by examining the burner flame. The flame may
be examined through the front flame viewer. The flame
must be stable and have blue colour. Some small yellow
tips are acceptable with propane gas. If the flame is yellow
or has excessive turbulence, check the gas manifold
pressure and the vent air intake system. If all these
are acceptable, call a qualified service technician for a
complete check of the furnace. Call also your gas supplier
to check the composition of the gas in use.
