Furnace Filter question

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grooving grandpa

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Apr 13, 2017
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177
I have  2004 Journey with basement A/C. Replace A/C filter twice a year which is beside bed frame. OMG, they don't make it easy. Here is my dumb question. I don't see anything in the Operators Manuel about a Furnace Filter. The A/C output vents are on the ceiling and the furnace vents are on the floor.Is the air return for the A/C also used for furnace return

Thanks
 
On my 2004 Monaco La Palma the furnace does not have an air filter. 

The roof air conditioner filters are washable on mine so I wash them a couple times a year.
 
As was explained to me.....The furnace doesn't need a filter.

I had the same question when I first got our TT :)
 
Interesting, I guess are rigs are Dust free for our furnace, but our stick house us is not. Is it because the A/C fans draw air from the outside, while there is no outside air to effect the furnace?
 
grooving grandpa said:
Interesting, I guess are rigs are Dust free for our furnace, but our stick house us is not. Is it because the A/C fans draw air from the outside, while there is no outside air to effect the furnace?

Not quite...As best I can understand/explain

The AC recirculates the same air in the RV. The air must pass though tight fins that can get clogged with dust and dirt. Hence the need for a filter to trap dust.

The heater also recirculates the same air however the heat exchange has larger gaps. Any dust or dirt would just blow on though.

I consider adding a filter to the heater. But everything I could find stated that the filter could hinder the air flow.

The above information is based on owning a TT for 3 months....So not so much an expert...Just a guy with a keyboard.
 
Finally, I understand. Great explanation. Tell it to me again in 10 minutes!! At my age in 10 minutes I will forget your explanation.
 
grooving grandpa said:
Finally, I understand. Great explanation. Tell it to me again in 10 minutes!! At my age in 10 minutes I will forget your explanation.

Tell you What again?...I forgot what we were talking about....Man it's cold in here...Turn the heat up
 
Somewhere I got a thin electrostatic filter I used in my MH for the furnace.  It went with the MH so I no longer have the name but search with google for them and see what you find.  I had to trim to fit but it was effective and only about 1/4"thick.  Kept the cat hair out and a lot of dust too.

Hopefully the new owner will see this post and provide the name of the filter from the spare I left in the MH.
 
I?m not an HVAC guy and I don?t play one on TV either, but I?m sure the reason the AC has a filter and the heater doesn't comes down to the fact that the AC Evap coil fins are reallyclose spaced and can clog really easily. Where in any real heater the air is pushed around giant tubes that can also prettymuch burn off dust as it lands. Dump the house filter and you're looking for trouble
 
my 2004 Adventurer has a house type furnace filter under the bed for the basement furnace, a/c. there is a small door with a finger hole in it to access.
 
mdka99 said:
my 2004 Adventurer has a house type furnace filter under the bed for the basement furnace, a/c. there is a small door with a finger hole in it to access.
Your LP furnace won't have a filter, the basement heat pump does.
 
mdka99 said:
my 2004 Adventurer has a house type furnace filter under the bed for the basement furnace, a/c. there is a small door with a finger hole in it to access.

My 2004 Adventurer has TWO filters under the bed, different sized filters. I just changed them after 6 months. They weren't clogged but I thought 6 months was a good habit to get into.
 
I'm guessing, but because return air is a conglomerate of open space getting back to the furnace rather than a duct, there is no practical place to put a filter other than on the furnace.  If it was on the furnace they would have to provide access, so the easier, and probably safer approach, is no filter.
 
For my basement air conditioner I use Filtrete brand filters(I have asthma/COPD),the filters got dirty so quickly I had to change them once a week at first, after a few months the interior of our MH must have gotten cleaner, as I then went to once a month when full-timing. Our LP furnaces have no air filter, so I bought a package of 3"X10" filter material and covered the bottom sides of the floor registers, which works quite well. An added benefit is, the filter material prevents stuff from falling into the duct-work.
 
If you restrict the the air flow on the furnace it might not operate as designed. They are designed for a certain CFM air flow or the sail switch won't operate or it might run hotter. Apparently you got away with your filtration addition (so far.)

Also Coleman-Mach/Winnebago recommends an inexpensive air filter for the basement air to maximize air flow. At 24,000 BTU, the basement air performance is marginal for a large full body paint multi slide RV in a hot summer situation.
 
I've seen only one RV LP furnace that had a factory-provided air filter system. The furnace was mounted in the basement of a DP with an air plenum behind it and the plenum opening in the floor above. A common a/c & furnace type filter simply fit into the opening in the floor.

As Mile High noted, there is no convenient place for a filter at the furnace inlet of either an Atwood or Suburban LP furnace. You have to make some sort of housing around the air return opening and set the filter in that.

Atwood's install & service manuals state that intake filters are NOT recommended, for the air flow reasons that John noted. From the Atwood Service Manual:

Do not place any types of air filters in front of or behind the return air door.
Blocking this area will substantially decrease the return air causing - less
air delivery to the heat registers - short cycle of the furnace - limiting of
the furnace.
 
Gary RV_Wizard said:
I've seen only one RV LP furnace that had a factory-provided air filter system. The furnace was mounted in the basement of a DP with an air plenum behind it and the plenum opening in the floor above. A common a/c & furnace type filter simply fit into the opening in the floor.

As Mile High noted, there is no convenient place for a filter at the furnace inlet of either an Atwood or Suburban LP furnace. You have to make some sort of housing around the air return opening and set the filter in that.

Atwood's install & service manuals state that intake filters are NOT recommended, for the air flow reasons that John noted. From the Atwood Service Manual:
:)) :))

He added filters to the floor outlets (registers) which I think would have the same effect and caveat as inhibiting the return air.
 
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