Mystery Furnace and it's filter location?

[madeintaiwan]

Hi there all,

I am basically the handyman/super for my mother-in-laws place. I live in the back (converted 4 car garage plus 65 airstream overlander). We (she) has a pair of furnaces in the basement that have no discernable make, model or serial. They do have a honeywell control on the front face and a couple of worn out warning stickers but that's all. I've attached a photo.

What i'm trying to do is: a. see if these have filters on the incoming air side (which I assume they do) and b. replace those filters. What I could use some help on is where to look for those filters. Googling around a bit I see that typically there is a filter right in front of the intake. Is that what I should be hunting around for? The intake manifold connection to the furnace?

Thanks as always for the help.

Nathaniel

[RegUS_PatOff]

Air Filter (if any) would be where the Return Air Duct enters the Furnace.

[madeintaiwan]

Thanks RegUS,

Could it be that there is/are no filter/s? Is it something that a HVAC installer usually constructs, ie a receptacle for a filter?

[RegUS_PatOff]

I'm not a Furnace master, but there may be no Filter..

It looks like those Funaces may have been converted from Coal to Natural Gas.