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5. Reinstall the inspection door
➂
. Snug the screws but do not overtighten and crush the insulation.
6. Reinstall a turbulator in each tube approximately flush with the tube ends. The end of the
turbulators are formed such that the end will bind within the tube end and lock the turbulator in
place.
7. Reinstall flue box front wrap
➀
.
Figure 13. Models 032 thru 200 Heat Exchanger
Models 020 thru 025 (see Figure 14)
1. To gain access to the inside of the combustion chamber, detach the burner from the furnace and set
it on the floor of the vestibule (see Figure 14, Item
➂
). The burner is attached to the furnace studs
with four nuts. Conduit lengths allows this movement of the burner without disconnecting wiring.
The union on the gas line must be opened.
2. Remove the flue box front wrap
➀
.
3. Remove and clean the turbulator
➁
from each tube and clean the flue box.
4. Clean each tube with a 2
1
⁄
2
" round flue brush.
5. Remove the brushings and if required clean the combustion chamber and header through the burner
mounting tube.
6. Reinstall the burner.
7. Reinstall a turbulator in each tube approximately flush with the tube end, locking them in place with
the wedge clips on each turbulator.
8. Reinstall flue box front wrap
➀
.
Figure 14. Models 020 thru 025 Heat Exchanger
Leakage Symptoms
1.
Odor –
Odors in the building are usually being brought in through the outdoor air intakes and do
not indicate leakage from the furnace. Check for down draft conditions and check the location of the
flue exhausts of other equipment that may be pulled into the outdoor air intake. A major and
obvious furnace rupture can be a source of odor. In general, small leaks in a furnace will not be a
source of odor or danger because the pressure created by the supply fan is greater than the pressure
inside the furnace. Therefore when the supply fan is operating, leakage will be
into
the furnace, not
out of
the furnace and into the air stream. If the control system is such that the furnace comes on
and warms up the heat exchanger before the supply air fan comes on, and there is odor when the
supply fan first comes on, this could be caused by leakage. During the time the furnace is on and the
supply fan is off the leakage would be out off the furnace and then when the supply fan came on it
would blow those products of combustion into the supply duct.