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mathew stouffer
12-10-2010, 07:20 PM
This was an older home built in the 60's with a new HVAC system. The furnace is located in the basement and the return air is next to the furnace, but this is the only return in the system. Is a return needed on the first floor.

Robert Hronek
12-10-2010, 08:14 PM
Returns are needed on the main level. You have a chance of the furnace and water heating backing drafting CO into the house.

I was in a house with signs of the water heater and furnace back drafting. I looked and found the panning was not capped on the end of a couple of return runs. On top of that that builder had put screens in the returns and they were plugged. Most if not all the return air was being pulled from the basement.

Brandon Whitmore
12-10-2010, 10:15 PM
What type of furnace (oil/ gas, or electric)?

mathew stouffer
12-11-2010, 07:16 AM
80% 100,000 btu gas furnace, 2007.

Jack Feldmann
12-11-2010, 08:36 AM
First of all the return should not be next to the unit.

Are you sure there there were not returns in the rooms upstairs?

H.G. Watson, Sr.
12-11-2010, 08:42 AM
Can't speak to the pictured as my own questions as to the accuracy of the information provided, except to say that there is a minimum six foot rule as to recirculating/returns and Cat 1 combustion equipment.

I'm assuming NG, I didn't verify my spotty memory, but IIRC UT uses NFPA 54 (NFGC) not I-Code IFGC-based.

Is the question really return air, ventillation air, or combustion air - I'm not too "clear" as to what is actually described/represented as (limited view)pictured here.

Some more information and more photos (overall perhaps) would be much appreciated and helpful here, M.S.

80 percent couldn't be sealed combustion to exterior only sealed, supplied combustion air.

Pressure differentials as well already mentioned regarding spillage.

Basement area finished or unfinished.

Don't actually see an open return grill, anywhere (Edit: Correction! I missed the grill down below bottom right of the picture!!! :o That doesn't belong, none within six feet, and especially not in basement near floor level!). I think I'm seeing a sheet metal square patch on a return plenum/perhaps where once existed a humidifier appurtuance (suppose it might have also once been additional access to a a/c coil or condensation pan or air-cleaner/filter)and some insulated duct coming from/to what, a blower fan or an air-to-air exchanger or HRV perhaps?

The crochetted scarf, table runner, or whatever draped there is of particular concern - although since equipment not well pictured, really don't know what we're seeing.

Return from the finished living areas at or above grade is non-existant? really? That would lead to some serious pressure balancing issues - take it the home leaks like a sieve then and has tremendous bypass to open attics/and/or unconditioned, unsealed crawls/ventillated basement, etc..

Rod Butler
12-27-2010, 08:56 AM
wow, had a lengthy post typed out but lost it. Probably a good thing. :o

Return air near the floor in the basement is almost a necessity to maintain winter comfort but I don't think that is the issue. Looks to me like the RA opening is in the same room as the furnace which could be a dangerous as well as improper installation.