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Fan Delay
Fan on time is 1 to 30 seconds and non adjustable. Fan off
time is 60 to 120 seconds and non adjustabe.
Limit Control
Limit Control — Do not adjust from factory setting.
Burner Adjustment
The following instructions are essential to the proper op
eration of ELO183DH series oil furnaces. To prevent soot
ing and prevent premature failure of the heat exchanger,,
these instructions must be followed in sequence:
1.
Draft
—This test should be taken at the breach be
tween the outlet of the vent connector and the baro
metric draft control. Generally a 1/4” hole will need to
be drilled for the draft gauge to be inserted into the vent
connector.
A minimum of 0.03 draft must be established without
the burner in operation. With the burner in operation,
the draft should be 0.04 to 0.05. This is VERY critical to
the flame retention head burners.
Oil furnace installations also require careful inspection
to make sure the chimney is in good shape and can ac
commodate the products of combustion. The temper
ature in the unconditioned space will also affect the
draft if long vent connectors are allowed to get too
cold.
2.
Overfire Draft
—This test should be taken with the
burner in operation. Remove the plug from the center
of the inspection port. Insert your draft gauge into the
hole.
A reading of the overfire draft should be 0.02 less than
the reading found in the vent connector. If a positive
reading is seen at this point, the combustion fan is
pumping too much air into the heat exchanger. Make
the necessary adjustments with the air shutter or air
band.
3.
Smoke Test
—The smoke test should be taken at the
hole drilled in step 1.
Air Band
(Secondary)
Air Shutter / Band Adjustment
Loosen this screw
to adjust air band.
Air Shutter
Air Band
Figure 15
Using a smoke test gun, adjust the air so that you will
have just a trace (between 0 and #1) of smoke. If the
burner is producing more than #1 smoke, adjust the air
shutter (primary) and air band (secondary) to reduce
the smoke. See figure 15. To adjust the air shutter,
loosen the top screw on the air shutter (and lower
screw, if necessary). Then, rotate the shutter until the
desired smoke level is achieved. If smoke cannot be
reduced to the desired level by moving the air shutter,
adjust the air band to increase the air. To adjust the air
band, loosen the air band screw and rotate the
band.
This is the
starting
point.
Do not stop here.
4.
CO
2
Test
—Again, take this sample at the vent pipe.
With the unit firing at a trace of smoke, take a sample
of the CO
2
. From the results of this test, a “window of
operation” will be determined. This window of opera
tion establishes some tolerance. The tolerance the in
staller builds in provides room within the set‐up for
those things which might affect combustion. Those
things which might affect combustion can then do so
without causing the unit to start sooting/smoking.
Things which might affect combustion include a nozzle
going bad, draft that changes during different climatic
conditions, dirty oil, dirt obstructing the air inlet, etc.
To build in a “window of operation,” set up the burner to
be 2% less in CO
2
. For example, if you find a reading of
12% CO
2
, adjust the air shutter (and air band, if neces
sary) to increase the air and drop the CO
2
to 10%.
5.
Retest the Smoke
—With a drop in the CO
2
and in
crease in the air you should see that the smoke has re
turned to 0.
6.
Retest the Overfire Draft
—This test serves to con
firm that you have not increased the air too much.
Again you do not want a positive pressure at the test
port. It should still be 0.02 less than the draft pressure
reading taken at the breach. You may need to increase
the stack draft by adjusting the barometric draft con
trol.
7.
Stack Temperature
—Take a stack temperature
reading in the vent pipe. Subtract the room air temper
ature from the stack temperature. This will give you the
net stack temperature. Use the efficiency charts pro
vided in most CO
2
analyzers to determine furnace effi
ciency.
8. When the proper combustion and smoke readings
have been achieved, re-tighten the air shutter
screw(s) and air band screw.
Service
Servicing Filter
NOTE - Under no circumstances should the access panels
to the blower compartment be left off or left partially open.
1. Throw‐Away Type Filters — Filters should be checked
monthly and replaced when necessary to assure prop
er furnace operation. Replace filters with like kind and
size filters.
