Furnace Ideas / Help

-
LO23M8B

LO23M8B

Well-Known Member
Joined
Jan 30, 2019
Messages
2,242
Reaction score
1,342
Location
Michigan
Hi guys and gals. I just installed a 95% furnace in my barn (almost a shop) and I am concerned about all the condensation. I'd like to run it than shut it off but with all the condensation I'm afraid of the coils may get water in them and freeze. Any thoughts ideas? Thanks.
 
Last edited:
Too bad you didn't find this out sooner. It just might be an issue, depending on how the internals and condensate drain is made. Some of these use an (typically) external PVC trap system to keep the combustion gasses (under slight pressure) from exiting through the drain system and into the heated space (house). If this is a "big ol" barn a little bit of gas leakage might not hurt. You MAY be able to modify the drain so that the condensate can all escape along with a little bit of combustion gas, which might not hurt in a large ventilated area

Going to need a link to the furnace documentation/ install/ service literature and some photos of the installation and drain/ vent hookups
 
I tried to send you a PM, talk with you on the phone. Clean out your in box or send me your number?
 
You should have a trapped condensate drain off the furnace that will collect the condensate accumulating in the vent. Make sure it's trapped and dumps in an inoffensive location.
 
72Dinger said:
You should have a trapped condensate drain off the furnace that will collect the condensate accumulating in the vent. Make sure it's trapped and dumps in an inoffensive location.
Click to expand...
I already said that, essentially, and am suggesting that if the barn is well ventilated, that this is not an issue for combustion gas. And or, --that this trap be modified or eliminated. The trap, at the least, is usually the freeze-up problem. Since it is a trap, it prevents condensate from fully exiting.

If the furnace is close to an outside wall, or other drain/ sump area such as a "dry well" you may be able to simply eliminate the trap and create a "for sure" gravity drain down and out. Make sure it is insulated all the way to the drain point and make sure it cannot "trap."
 
67Dart273 said:
I already said that, essentially, and am suggesting that if the barn is well ventilated, that this is not an issue for combustion gas. And or, --that this trap be modified or eliminated. The trap, at the least, is usually the freeze-up problem. Since it is a trap, it prevents condensate from fully exiting.

If the furnace is close to an outside wall, or other drain/ sump area such as a "dry well" you may be able to simply eliminate the trap and create a "for sure" gravity drain down and out. Make sure it is insulated all the way to the drain point and make sure it cannot "trap."
Click to expand...
Cleaned out my in box. Thank you.
 
I'll go out to the barn and take some pic in a minute.
 
Nice talking to you. I'm off looking for docs

Looks like vent is standard "drain waste vent" PVC, I'd use 2" and drop the 3" reducer if you can. Needs to be pitched and insulated

Haven't figured out the drain/ trap yet
 
Last edited:
Again how is this positioned, AKA upflow, downflow, or horizontal?

Post photos here on the thread, should be an "attach" button but you need a source to point it to IE whatever device you access the forum
 
67Dart273 said:
I already said that, essentially, and am suggesting that if the barn is well ventilated, that this is not an issue for combustion gas. And or, --that this trap be modified or eliminated. The trap, at the least, is usually the freeze-up problem. Since it is a trap, it prevents condensate from fully exiting.

If the furnace is close to an outside wall, or other drain/ sump area such as a "dry well" you may be able to simply eliminate the trap and create a "for sure" gravity drain down and out. Make sure it is insulated all the way to the drain point and make sure it cannot "trap."
Click to expand...

If the trap is necessary and there is potential for freezing, heat tracing and then insulating the trap may be a solution. That is commonly done in low-temp refrigeration. A 120V heat trace pulling about an amp could coexist on the furnace circuit.

Hopefully you guys can talk it through. I'd be curious to see the setup and happy to provide my 2 cents. My expertise though is limited to a milder climate so my thoughts may not be applicable.
 
Here we go

E66724F5-DE9C-4820-9E1E-E4F3D88FB09C.jpeg
 
72Dinger said:
If the trap is necessary and there is potential for freezing, heat tracing and then insulating the trap may be a solution. That is commonly done in low-temp refrigeration. A 120V heat trace pulling about an amp could coexist on the furnace circuit.

Hopefully you guys can talk it through. I'd be curious to see the setup and happy to provide my 2 cents. My expertise though is limited to a milder climate so my thoughts may not be applicable.
Click to expand...
Yeh I mentioned heat taping it. If he can eliminate any trap/ trapping in the furnace drain, this would simply allow "a little bit" of warm combustion gas out the drain, which would help keep it warm. Heat tape may well be one way out tho
 
You for sure want to insulate the outgoing combustion vent. The air intake is not critical. Too late now, but I would not even have run the air intake outdoors in this application.
 
I can change the intake no problem. I can insulate the exhaust also. Anything that would help.
 
What is make & model of the furnace?

From pictures, I don't think a trap would be required as it appears located positive side of the blower - it would drain regardless. But without a trap it would be noisy.
 
It says IR on the manual and 67 dart said it's a Trane by the model number.
 
Well I am stuck. After looking at your photos and the destructions, it appears that any trap function is built in. It MAY be the white plastic fitting there where the drain connects. An easy way of handling that would be to try a very small heater right inside the furnace. One way would be either a single low wattage 220Vbulb, but operated on 120V. A 100W 220 bulb on 120 would be 25 W and last a long time, and you would not need that much. Alternatively, if you could "hack" up a couple of sockets and run them in series, this would run two 120V lamps at half voltage. If you ran a pair of say 15W or 25W bulbs (not LEDS but incandescant) that would give you 1/4 of 50W or about 15W and should be plenty with the door on.

EDIT. I was going to suggest "if you dare" to disassemble that white plastic device and see if there is a "stand pipe in there that would form a trap.
 
You must log in or register to reply here.
-

Back
Top