LAARS NeoTherm NTV (Sizes 150–285 MBTU/h) - Service Manual - Manual (Page 73)

63 Service Manual NeoTherm 80 - NeoTherm 285
15. Figure C5-11 shows the inside of the heat exchanger.
Black carbon soot can build up on the coils as a
result of poor combustion, combustion air problems,
venting problems, or short-cycling. This can reduce
the efficiency of the unit or plug up the flue pas-
sages. Your job is to get all of this extra material out
of the heat exchanger so that it can operate properly.
The heat exchanger in Fig. C5-11 is new, so it is
clean. Figure C5-12 is a photo of a dirty heat ex-
changer.
This appearance is normal. However, sometimes
a heat exchanger can be really dirty. Figure C5-13
shows an example.
Cleaning Procedure:
1. Attach one end of the hose to the condensate drain
located under the heat exchanger. Run the other
end of the hose to a bucket or drain. See Fig. C5-14.
Fig. C5-12 - Dirty heat exchanger
Fig. C5-13 - Very dirty heat exchanger
Fig. C5-14 - Drain hose connected under the
heat exchanger
Cleaning the Burner and Heat Exchanger (continued)
Refractory
material
Stainless steel
coils (dirty)
C5
cont.