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5.4.2 Burner System Checkout
Once the heater starts operating, make the following checks and adjustments:
If you are unable to obtain the proper adjustments, do not run the heater. If you
cannot resolve the issue, call Technical Support for assistance.
Fan Operation:
Within the first few minutes after the burner fires, make sure that the fan
begins to operate and directs warm air into the room. If not, this may indicate a problem with
the unit. Shut down the heater and diagnose the issue or call for assistance.
Exhaust System:
Check that the flue exhaust is flowing properly, and there are no exhaust
leaks inside the building. Check the outside flue pipe to ensure that no black smoke is present.
If smoke is present and the draft is correct (see adjustment procedure below), call for
assistance.
Draft Adjustment:
After operating the heater for about 15 minutes, verify the draft gauge is
reading 0.04 inches of water column (“WC).
Draft Gauge
Knob / Weight
Damper Door
0.04 Inches WC
Draft reading and adjustment
•
If the draft gauge reading is less than 0.04 inches of WC: Loosen the adjustment weight
on the barometric damper door, then slide it to the right or closer to the damper door
pivot axis, and retighten it.
•
If the draft gauge reading is more than 0.04 in. WC: Slide the weight to the left or away
from the damper door pivot axis, and retighten it.
•
Verify that the reading remains at 0.04 inches of WC with exhaust fans and vented
appliances on in your building and all doors and windows closed.
A negative pressure inside the building may impede intake of combustion air to
the burner, which may result in a hazard from smoke inhalation and/or fire. Use of exhaust
fans in your shop without adequate make-up air may create a negative pressure. There are
other possible causes as well. Corrective measures must be taken if the correct draft setting
cannot be achieved.
If you are unable to adjust the damper door to obtain at least 0.04 inches WC,
there is not enough draft for proper exhaust. Do not run the heater under this condition. If you
cannot resolve the issue, call for assistance.
Summary of Contents for MX 75
Page 2: ......
Page 41: ...8 Appendices 8 1 Wiring Diagram ...
Page 42: ......
Page 43: ...34 Call 1 888 370 6531 for Technical Support 8 2 Primary Control Instructions ...
Page 44: ...35 Call 1 888 370 6531 for Technical Support Not used with RES 75 kBTU h units ...
Page 45: ...36 Call 1 888 370 6531 for Technical Support No latch up with RES 75 kBTU h units ...
Page 46: ...37 Call 1 888 370 6531 for Technical Support ...
Page 54: ...45 Call 1 888 370 6531 for Technical Support 9 ...