Filter for Atwood furnace

[Hewshal_53]

I am considering putting a lightweight foam or fiberglass filter behind the intake grill on my Atwood 8531 furnace. The opening is 10 x 24". Comments

[rbpru]

The big question is why would you put a filter on a furnace that by its very nature is designed to be used it a dusty, dirty, semi out-of-doors environment.

Most people do not associate sterile with RV camping. Most often folks are tracking the out-of-doors into an 8ft. by perhaps a 32ft. box, that is less footage than a typical 15 x 18 living room.

Like most anything, there probably is a way to do it but what is the objective?

[Community Alumni]

Really it's not necessary to filter any of the furnace air. The reason why you need a filter on the AC is the protect the evaporator coil. The evaporator coil consists of tubes surrounded by very closely spaced fins. Dirt and dust can quickly plug up the coils. This will eventually lead to a reduced air flow and icing issues.

The furnace on the other hand doesn't have a tightly packed coil like the AC. The heat from the propane flame blows into large burner chambers. The blower then blows the interior air over these chambers which pick up the heat. There's not a whole lot of places where dust can get trapped and build up. Most of it just blows back out through the ducts. The only real area of concern is in the fan housing. Over time dust can accumulate between the fan and the housing. Just vacuum out the housing after several years and you'll be good to go.

[BarneyS]

gmw photos wrote:
Poster Chris Bryant works on this stuff for a living. Probably a good idea to heed his real world advice.

I agree with the above. Chris has a very helpful website and is usually spot on! I have followed his advice numerous times and have not been disappointed yet. 🙂
Barney

[gmw_photos]

Poster Chris Bryant works on this stuff for a living. Probably a good idea to heed his real world advice.

[Hewshal_53]

Wow, Thanks for all of the responses. Read a few remarks on other forums where some individuals had installed mesh filters to stop dust and dirt from entering their furnace compartment. Idea was to prolong furnace life and prevent the smell you often get when starting up in the fall. None of my Atwood literature said anything pro or con about filters, and yes I probably should have called before asking a dumb question. Meanwhile, I shan't be a trial and error statistic and will think outside the box on others things.

[Chris_Bryant]

rhagfo wrote:
Wow, to all that worry about burning up the furnace with a filter, do you really think the intake is that well sealed?? I have a paper filter behind the grill, but it draws from cabinets under the sink also!

A, it won't burn up, it will cycle on the limit switch, shortening the lifespan.

B, if it's not drawing through the filter, why have it?

[rhagfo]

Wow, to all that worry about burning up the furnace with a filter, do you really think the intake is that well sealed?? I have a paper filter behind the grill, but it draws from cabinets under the sink also!

[Chris_Bryant]

Use a stand alone filter instead. Atwood (and Suburban) is very clear about no filters. They did have an add on electrostatic filter for a while, but they are as rare as hens teeth.

[wildtoad]

I don’t think you really want to reduce airflow to and from the furnace. There is a reason the manufacturers don’t put filters on them. I’d call Atwood if you really think you must install a filter and see what they say.

[SoundGuy]

old guy wrote:
well nothing like burning up you furnace and maybe even your TT. better sleep with one eye open at night. your furnace will overheat so don't even think of it. if the builders wanted a filter they would have put one in. I will bite my tongue for now.

Seems you haven't. :S

[old_guy]

well nothing like burning up you furnace and maybe even your TT. better sleep with one eye open at night. your furnace will overheat so don't even think of it. if the builders wanted a filter they would have put one in. I will bite my tongue for now.

[Lynnmor]

He may have seen the dirt in the AC filter and concluded that an air intake at floor level would be even worse. :S

[SoundGuy]

Hewshal#53 wrote:
I am considering putting a lightweight foam or fiberglass filter behind the intake grill on my Atwood 8531 furnace. The opening is 10 x 24". Comments

Why? Millions of these furnaces are in use, the manufacturer never deemed a filter necessary, why would you? :h

[ScottG]

It will have to be a very free flowing filter and as you probably know, that type doesn't do much.
Probably worth trying though. If you block it too much the sail switch will keep the furnace from working.
If you try it please come back and let us know how it worked. It's been discussed many times but I don't think I've ever heard of someone actually trying following through.