2006 Furnace fan bearing noise (Hydroflame?)

[Lotus54]

I took a look at my furnace (Atwood 8012-II)
It appears that I can probably get the motor out from the front side of the furnace. I looked at the parts manual, but it wasn’t really clear. I couldn’t find anything that talked about taking it apart.
If it comes out the rear- it would be rather more trouble, required some wood removal (might not be too bad).
I’m not sure how hard it would be to completely remove it. I’ll look into that also. (It would be nice to do on the bench).

There is certianly plenty of room to install an Espar diesel heater, but after lisenting to the Espar that comes with the van (aux engine heater) it is pretty noisy. I would look into mounting it underneath if I was to change (although that would be a lot more work).,

Likely I’ll just fix the bearing/bushing and keep using it- at least for the time being. I like using diesel though, since that is a LOT easier to fill then mucking about with the small propane tank.

I’m pretty darn sure it is a bearing/bushing. It makes not excess noise until it runs a little bit, and has very much a bearing ‘squeal’ to it.
The YouTube videos I saw about replacing the motor was entirely different than it would be on this model- those had external access and this certianly does not.

Mark

[InterBlog]

Originally Posted by Lotus54

... after listenting to the Espar that comes with the van (aux engine heater) it is pretty noisy. I would look into mounting it underneath if I was to change (although that would be a lot more work).,
...

There are a number of YouTubes on this exact procedure. IMO, Kenetube's is the best, but I'm not going to link it here because it will consume a big blob of forum space by embedding the vid whether I want it to or not.

[Lotus54]

I watched it- while it was under the passenger seat (I have a battery there)- it was pretty good to see the complete job on a video.

I wonder if those are quieter than the ones that come with them? (I think you have one also?)

If quiet, there is plenty of room to install one in place of the propane one. OR just mount underneath and duct it. So either one could be used.

I think I’ll consider doing that. Might be nice to have both ways.

Thanks for the info
Mark

[GM Airstream]

Indeed... I leave the screens on when not in use.. but when it get REALLY cold outside... and we need the heater. .. then we take the screens off...

The manufacture doesn't want anything blocking the flow of air into or out of the heater... we found that the intake can get iced up... and stops the heater from working because of the sail switch not actvating... but, others reported that they got booming backfires as the heater cycled...

So we normally now take them off when we are using the heater in cold weather....

I know some are saying that works and not... because someone forgets to take them off.. ouside.. but we put a tag on the heater thermostat... that says ..

CAUTION... HEATER INLET AND OUTLET HAVE SCREENS ATTACHED. REMOVE BEFORE USE...

I would think that if its below 50 or so outside... that their won't be many bugs out to do damage... so the screens are their to just protect the heater section while its in storage or not used .

I also found that the springs ended up being a weak point in them.... So instead of using a spring to hold it on we also went with a longer screw for the top that already exist.. and put a small washer on the screw.. that then goes through one of the openings and locks it down.

The bottom one we added the longer screw and a small clip to hold it up tight with...

Seems to work.. haven't lost one of them yet... over the year we added it to keep the little buggers out..

but... best also to pull the heater once a year and check for bugs and dirt... you only need to take the chamber cover off.. and also the gas inlet and ignitor covers... and with a shop vac... blow the old dead bugs, dirt and rust out... as the manufactue says...

Happy camping..

[PeterDB]

I had a similar Atwood fan squeal that occurred just after the propane ignited. I removed the furnace from the trailer and replaced the fan motor, adjusted the two fans for better clearance, added a few sheet metal screws and some high temperature gasket goop to reduce metal-on-metal vibrations. I lined the cabinet where the furnace goes with sound deadening material and reinstalled the furnace, It is significantly quieter and the squeal is gone.

[pkm123]

What AS model did you do the repair on? I have a 2007 Airstream Bambi with the Atwood heater and it is loud when the fan comes on and has that early squeal. How did you get the motor out? Does the furnace come out easily from the front? Do you know of any good repair videos? I would love to make the unit less noisy. Any advise would be appreciated.
Thanks,
Ken

[PeterDB]

2014 AS19 International CCD. The furnace slides out into the trailer after removing the grill, disconnecting the gas line and wiring, and removing the four screws which is all that keeps the furnace in place. Don’t forget the routine safety stuff like turning off the propane at the tanks, switching power off, etc. The rear end of the furnace is held in place by the exhaust tube that is attached to the outside of the trailer. I guessed at the noise source considering that it’s the main moving part. I bought an OEM replacement from Amazon. I have an exploded parts diagram which makes it easy to see which screws need to come off to replace the motor.

The furnace box is not designed by someone who actually has to sleep with the thing. A bare minimum of screws holds it together. I tapped on it to identify metal moving on metal and added screws where I could and high temperature Permatex where a screw would have caused interference with one of the two fan cages.

I bought some Noico aluminum/butyl sound deadening material from Amazon and lined the sides, top, and bottom of the cabinet (the space at the bottom of the sink cabinet) with the Noico, then reinstalled the furnace directly on the Noico sheet. Much quieter now in general and the startup squeal is gone. Our camping buddies have a 2015 AS 19 International which has a much nicer furnace that is assessable from the outside and is significantly quieter than ours even with my mods.

[pkm123]

Peter,
Thanks for the detailed description of the repair. My fan squeal is intermittent and after the initial startup goes away for now. It seems that most of the blower noise comes from out of the front grill which is just a loud blower fan noise. Did you find that by lining the cabinet that the furnace sets in with the insulation
quieted the noise of the fan and the moving air coming out of the grille?
And was your new OEM motor quieter. It seems to me that most of the furnace noise is from poor design and using a squirrel cage fan. Any way, if it isn’t to much trouble I would like the links to the amazon items you ordered and where you got the exploded diagram. If you think soundproofing would significantly reduce the blower noise I would attempt your modification. I don’t know how they could make a furnace any louder. It is very annoying. I had the same furnace in a Lance Camper and it was also loud and annoying. I have tried a Heater Buddy but they stink and are not good for condensation.
Thanks,
Ken
Merry Christmas!