Testing a used furnace before install.

[racer8432955]

I was given a like new Bryant household furnace (natural gas) from a carpenter buddy to hang in my detached outbuilding I am remodeling. The furnace was out of a teardown building, but appears to be not very old at all. I'm guessing it operated fine, but I don't want to go thru the work of hanging it if it doesn't. Or at least, I would like to do any necessary repairs on the ground.

Does anyone have any suggestions on what tests to perform and what to look for? My first thought, the easy one, temporary wiring it up to see if the blower fan runs. What about it getting gas, and see if it will light? I don't have the gas run out to the shop yet, but my attached garage does have a gas line stubbed out there. I could get it up there (thru the 400" of snow) to connect to gas.

Any advice / thoughts appreciated!!

 

[D.J.]

is it 110 or 220? use the stub out to install a quarter turn valve onto and wire and plumb it up and check it out and see if it works!

 

[racer8432955]

120V I believe, but i'll have to check to be sure. thanks

 

[rickairmedic]

Jerdman its is 120 Volt if its a gas furnace . Hook up a temporary 120 volt line to it . Then put a jumper wire between the W and the R on the control board and turn it on . With a Bryant or Carrier the blower motor will come on for 90 seconds . Then the fan induction motor will come on once the air proving switch closes the ignitor should come on and glow orange . Place your hand on the gas valve and you should be able to feel the solenoid open after the ignitor heats up ( just hold your hand on the gas valve once the ignitor starts to heat up.) Once you feel the solenoid open your done shut it off and hang it up . Also if you get me the model and serial numbers off of it I can tell you when it was made and what size it is .


Rick

 

[racer8432955]

Wow, thanks Rick. Thats exactaly the kind of info I was looking for. I'll get the #'s weekend and post. thank you.

 

[Hlidskjalf]

Oh yeah, don't blow yourself up.

 

[Dkramer]

If it is a condensing gas furnace, you will need to install it in the configuration it was in at the old building. I.E. if it was standing upright with the blower blowing down it would have to be installed that way. Unless you convert it to another position. Some can be converted to any position, some can only be converted to select positions.

 

[CraigFL]

Get out the CO meter to be sure the heat exchanger isn't cracked.

Check the exhaust temperature to be sure it's reasonably efficient.

 

[Mike in Ohio]

If it is a condensing gas furnace, you will need to install it in the configuration it was in at the old building. I.E. if it was standing upright with the blower blowing down it would have to be installed that way. Unless you convert it to another position. Some can be converted to any position, some can only be converted to select positions.

How can you tell if it can be converted to a different position?

 

[rickairmedic]

Mik,e most 80% furnaces come in two styles . Upflow which can usually be converted to be able to lay on its left or right side by reclocking the induction fan motor and downflow which are pretty much stuck in downflow configuration. Then you have 90%+ furnaces which unless you can rework the drain system you are stuck with either upflow or downflow. Also unless you plan to keep your garage above freezing at all times a 90%+ may not be a good idea as the water inside them can freeze and cause damage to the unit.


Rick

 

[Mike in Ohio]

Mik,e most 80% furnaces come in two styles . Upflow which can usually be converted to be able to lay on its left or right side by reclocking the induction fan motor and downflow which are pretty much stuck in downflow configuration. Then you have 90%+ furnaces which unless you can rework the drain system you are stuck with either upflow or downflow. Also unless you plan to keep your garage above freezing at all times a 90%+ may not be a good idea as the water inside them can freeze and cause damage to the unit.

Thanks Rick, I will probably have some questions for you when install it.It is a down flow propane unit I got off of craigslist. Definately not a 90%.
I have to get the insulation done first though.
Mike
Rick

 

[racer8432955]

Jerdman its is 120 Volt if its a gas furnace . Hook up a temporary 120 volt line to it . Then put a jumper wire between the W and the R on the control board and turn it on . With a Bryant or Carrier the blower motor will come on for 90 seconds . Then the fan induction motor will come on once the air proving switch closes the ignitor should come on and glow orange . Place your hand on the gas valve and you should be able to feel the solenoid open after the ignitor heats up ( just hold your hand on the gas valve once the ignitor starts to heat up.) Once you feel the solenoid open your done shut it off and hang it up . Also if you get me the model and serial numbers off of it I can tell you when it was made and what size it is .


Rick

Rick,
As I mentioned previously, the brand is Bryant. The model is 340MAV036060. Serial # is: 2997A02176. Also, I did find a manual on line, and it does say that it needs to be kept @ 32f + after initial start up, 90% efficent I assume. Since I live in Wisconsin, it has not been kept above freezing. What should be checked for freeze damage?
I was not thinking I would necessarily always keep the shop above 32. Do you think this model does not really suit my needs? Not a huge loss if so, it was free.
Thanks for your help!
John

 

[rickairmedic]

John it has a 3 ton blower in it and is 60,000 BTU's it was made the 29th week of 1997. With it being a 90% furnace you will need to keep the garage above freezing ( after it is put into use ) . The fact that you have kept it stored at under 32* may not be a big deal since it wasnt hooked up and any water that may have ben in it may have been able to expand. I would pour some water down the exhaust pipe on it and se where it comes out if it only comes out the drain then you are probably ok . You have a few options if you dont plan on keeping your garage heated full time ( to above freezing ) put it on Craigslist for $150-$200 OBO and hunt down an 80% furnace . Or your could just pull the blower assembly out of it and trash the rest and still look for an 80% furnace .


Rick