Gas furnace FHA filter
#1
07-03-19, 01:06 PM
Gas furnace FHA filter
I bought a home recently with natural gas fed Central HVAC. On the lower section of the furnace is the 'connection' for the duct system. It has a large pleated filter installed in between the furnace body and the duct work. The filter is about 24" square and 1" thick and is just slid into place. A lot of air can get in around it from the basement bypassing the return/feed duct system. Am I correct in saying that this should be a 'closed' system??
#2
07-03-19, 03:40 PM
From the picture, there appears to be a return air duct to the right of the furnace? Is that connected to the furnace? It seems that the return duct vents into the basement, and then the return air to the furnace, in turn, comes from the basement. Very unorthodox, but it might work, after a fashion. Please post more pix with a wider angle so we can see how everything goes together.
Did you hire a home inspector before you closed on the house?
Did you hire a home inspector before you closed on the house?
#3
07-03-19, 04:29 PM
The whole duct system comes in from above that point heading through that filter area. I attached a better pic of that area. An inspector did 'look' at the whole house.....but if it isn't burning or leaking they check off the OK box if you know what I mean.
#4
07-03-19, 10:04 PM
Group Moderator
Not the neatest job but it's ok.
The important thing is that the filter fits tight to the furnace to keep the dust out of the furnace. You could fashion some type of cover there to keep dust from being sucked in off the floor.
The important thing is that the filter fits tight to the furnace to keep the dust out of the furnace. You could fashion some type of cover there to keep dust from being sucked in off the floor.
#5
07-04-19, 05:54 AM
My thoughts were; Is there a cover of some sort that is missing. Also isn't a system like this supposed to cycle/recycle air from the areas being heated/cooled and not any other area?
#6
07-04-19, 10:20 AM
Group Moderator
#7
07-04-19, 11:01 AM
In post #3 the filter 'box' looks like it is taped to the duct and the bottom looks open. You are saying that the install was sloppy? That was my impression. Theoretically in a good system air is moved from the living area(s) and brought to the furnace/AC unit and either heated or cooled to the desired temperature. Then it is returned to those areas, repeatedly. Essentially I have a hole in my duct work because of all the outside air along with any airborne contaminants that this air filter assembly is allowing in.
#8
07-06-19, 09:46 AM
Member
With the tape there it's hard to tell if the return drop is properly connected to the filter holder.
There should be a cover for the filter holder - if it's nowhere to be seen you can tape over the filter for now so air doesn't leak through the gaps.
Some return air leakage is not big deal but it shouldn't be near a natural draft water heater, as room can be put under negative pressure and it can back-draft.
There should be a cover for the filter holder - if it's nowhere to be seen you can tape over the filter for now so air doesn't leak through the gaps.
Some return air leakage is not big deal but it shouldn't be near a natural draft water heater, as room can be put under negative pressure and it can back-draft.
justsumoldguy
voted this post useful.
#9
07-06-19, 10:38 AM
Member
Hi, does that arrangement have a track on the bottom as well as the top for the filter to slide into? I’ll bet the back is wide open also, any chance a 2” wide filter would fit there?
Ya, got to love HI’s
Geo
Ya, got to love HI’s
Geo
