Blankenship wrote:
Can anybody help me troubleshoot my Webasto air furnace? It's a model
HL32D. Normal operation as I heard it was: dosing pump running, then air
fan, and we had heat. The last three or so start-ups was, as I heard it,
and not knowing trouble was on the way: dosing pump running, air fan on,
air fan off, dosing pump on, air fan on, then we had heat. Now when
switched on, the only thing I hear is the air fan come on and run for a
while, 90 seconds or so I believe, then shut down with no heat. Voltage at
the heater terminal board before and during startup is 14.5 volts, with the
needle barely moving during startup attempt. Any help greatly appreciated.
Alan


This is an older post I posted a while back, which I totally forgot
about (sorry) after I found the problem, and for anybody interested
here is what the problem was: a bad glow plug which went bad because of
a bad fuel mat, I'm guessing went bad from "old age". The fuel mat is
very fragile and cracks easily (you'll see why if you have one in
hand), causing bad atomizing of the fuel and thus gunking the glow plug
and eventually failure of the glow plug. The HL32D is a fairly simple
unit to work on if you're mechanically inclined, and the shop manual
made it possible, which I ordered from my local Webasto dealer. I
ended up rebuilding the whole unit by myself with all new parts,
including the heat exchanger, as the shop manual says to replace after
10 years, which mine was right at 10 years ($$, but not $$$!). I can
now take the unit out of the boat in less than 10 minutes, which is
usually not necessary for replaceable parts such as glow plug, flame
detector. I now face new problems, which I believe are more than
mechanical, but now electrical, as I have replaced glow plugs, flame
detector, and had the unit running and putting out heat (with no smoke)
but doesn't start up on it's own after reaching set point temp. I'm
guessing now that I either have a bad t-stat, or 'black box' (or 'brain
box', conrol box, what ever it's called). I'm almost totally lost
reading schematics, so what I can figure out from all those line
pictures is either the 'box' and/or the t-stat. The troubleshooting
section kind of points towards these two. My next move is to pull the
unit and check the fuel mat first before going to my local dealer and
gatting him ($) involved. I'll be heading out of town for turkey day
before attacking my problem and if anybody has a solution or ideas for
me to check out first, I'd appprciate hearing from you on this forum
(now bookmarked!) before I go ($) route. Happy Turkey Day

updated e-mail address:

Tamaroak wrote:
What's the cruiser's opinion on these furnaces? I'm thinking of
installing their air 5000 and wonder how hard they are to put in and how
reliable they are. Are they noisy?


Don't know about the air furnaces but the hydronic (silly word, but
that's what they call it) heaters are great. They are very quiet IMHO-
mostly you hear the ticking of the fuel dosing pump which sounds about
like a small clock running at variable speeds. If there is any other
sound going on, you can't hear it. The fan & pump are almost silent, you
can hear them if you open the engine room access door & listen
carefully. When it fires at max you can hear a whooshing noise in the
exhaust but that's mostly when it is coming up to temp.

The biggest issue is that the things are tricky to install properly. Our
boat did not really have a good place to install it and I did not
realize this until already started on the job.

As for reliability, we have only had ours for two years but have had no
trouble. Open the fuel valve, push the button, and 10 minutes later the
radiators are HOT. I wanted specifically to heat up our head compartment
and it can be made into a sauna on the coldest nights.

fair skies- Doug King

"DSK" wrote in message
.. .
Tamaroak wrote:
What's the cruiser's opinion on these furnaces? I'm thinking of
installing their air 5000 and wonder how hard they are to put in and how
reliable they are. Are they noisy?


Don't know about the air furnaces but the hydronic (silly word, but that's
what they call it) heaters are great. They are very quiet IMHO- mostly you
hear the ticking of the fuel dosing pump which sounds about like a small
clock running at variable speeds. If there is any other sound going on,
you can't hear it. The fan & pump are almost silent, you can hear them if
you open the engine room access door & listen carefully. When it fires at
max you can hear a whooshing noise in the exhaust but that's mostly when
it is coming up to temp.

The biggest issue is that the things are tricky to install properly. Our
boat did not really have a good place to install it and I did not realize
this until already started on the job.

As for reliability, we have only had ours for two years but have had no
trouble. Open the fuel valve, push the button, and 10 minutes later the
radiators are HOT. I wanted specifically to heat up our head compartment
and it can be made into a sauna on the coldest nights.

fair skies- Doug King

I have an Airtop 3500 in a J/32 and it has had a few problems with
reliability. The installation is critical, especially the routing of air
intake hose. The plastic housing on the furnace is not very well-attached,
and if there is stress on the intake hose it can distort. This caused the
fan motor to be stalled on mine, which blew out the motor for a few hundred
$$ repair bill.

I can send a complete description of my installation by private mail if
desired, and there are a couple of photos on my J/32 web site:
www.sailj32.com

Don

What's the cruiser's opinion on these furnaces? I'm thinking of
installing their air 5000 and wonder how hard they are to put in and how
reliable they are. Are they noisy?

Capt. Jeff