"POOF" From LP Heater

[Jeff Miller]

Most likely the combustion chamber / combustion flue has wasp nests in
it.

It sounds like it is igniting, but not enough air flow, poof it lights
but blows itself out (not enough oxygen), the "three-strike" board will
reset and try again to ignite until three tries are unsuccessful.

If you're very lucky you will be able to remove the nests from the
outside, through the outside vents, small hooked wire and small
flashlight. If not so lucky, then the furnace(s) will need
removal/disassembly. Working on an LP furnace isn't to be taken
lightly, there are plenty of good RV techs out there who can carry out
the work safely. $100 savings is IMO not worth the risk.

While apart, the burner should be cleaned, a hacksaw-blade in each slot
tends to remove carbon nicely. Reassembly is fairly simple if you
remember what screw came from where, and where gaskets should be. Oil
the motor slightly while you're in there. The furnace MUST be leak-
checked after reassembly/installation, LP leaks might not be detected
by the LP shutoff/leak detector so don't stake your life on it.
Cleaning the burner slots and combustion chamber/blower should prevent
carbon build-up on the inside of the burner (and the outside of the
coach). Carbon/soot on the side of the coach is an indicator that there
is a problem with the furnace.

The NT-16 furnace can be changed in most cases to the newer-style NT-20
which is a bit noisier, if necessary.

- Jeff Miller


--- In WanderlodgeForum@yahoogroups.com, "trvlngnrs"
wrote:
>
> While outside, removing the polarity monitor, I noticed the bedroom LP
> heater would run for awhile then I would hear a "POOF". The heater
> would run for a few minutes and "POOF" again.
>
> I have already vacumed the areas I could get too, but really couldn't
> get to very much of the heater due to the metal box it's in.
>
> I've been told a couple times to clean it, but how? Do I need to
> disconnect the gas line and take it out? Is there a way to open up the
> heater box to clean inside it?
>
> TIA,
> Steve Harrie
> '86 PT38
>