New furnaces have to be same size as old furnaces???

[cn]

Hi,

I just have a quick question on sheet metal work. I am looking into replacing our home's 16-year-old furnaces x2 (see below), to be replaced by my local HVAC Co.

The questions are:

1. Should I get furnaces (let's say brand XYZ) with similar openings as right now so there is less "messing around" with sheet metal work.

2. Or any furnace can be made to fit into existing sheet metal openings???

3. Do most furnaces have similar opening sizes on RETURN and UPFLOW Ouput portions?

TIA

cn
Omaha NE
House Built in 1991.
* 1st Floor + Basement: 1991 TEMPSTAR Gas Furnace (5 burners ? 100K BTU)
* 2nd Floor: 1991 TEMPSTAR Gas Furnace (4 burners ? 80K BTU)

Tempstar Furnaces #: NUGI100DH03, L904166400

[oloenneker]

Hi,


1. Should I get furnaces (let's say brand XYZ) with similar openings as right now so there is less "messing around" with sheet metal work.

That sure makes it easier. Make sure that the existing furnace is the right size for the home to begin with. Your contractor should be able to do a heat load/loss calculations for you.

2. Or any furnace can be made to fit into existing sheet metal openings???

I can pretty much make any furnace fit with the use of transitional sheet metal fittings. Sometimes you have to modify the duct work, or re-do some of it to make it all work. It helps if you have a brake and a pitts in the install van. Hence why alot of companies use box vans... It's a shop on wheels.

3. Do most furnaces have similar opening sizes on RETURN and UPFLOW Output portions?

No, not always. Depends on the size of the furnace, and the existing duct work. See answer #2

[t527ed]

we have pittsburg machine and 4' brake in our install truck, anything we need to adapt is made at the job. with all of the new furnaces being shorter we always have to make something.

[6448craig]

Any good Heating and Air company with a good sheet metal man and shop will be able to make fittings for the new furnace to match your duct openings.

[tinmantu]

Personally, I stop in the job to be done before hand, take all my measurements and build it up at the shop. Makes for less downtime on the job and everything drops into place. I'm sure bigger companies don't have that luxury.