Furnace never goes into high fire, why?

yuri

By default from the factory I believe it is setup with the jumper on the board for true 2 stage op with a 2 stage tstat. Most guys use a single stage stat to save $$ and avoid running extra wire to the tstat. Not sure what the heck your installers or techs have done. It is fairly easy to figure out if you have the install manual. Will show you the jumper position for 1 stage stat or 2 stage stat op. Some even have an option for high fire only. Not sure what you have but a skilled tech with the manual or enough experience should be able to figure it out by looking at the board. Did a 2 stage 95% for Sis not long ago. The board has letters on it for the jumpers but w/o being there I can't tell you exactly what to do. Superior Htg sold a lot of Rheems and probably has a few skilled techs.

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tfunk

You still in the biz? I'd pm you but I need 20 posts to send PMs

JJboy

Best: W1 and W2 from furnace control board connected to W1 to W2 thermostat ( 2 stage )

Good: W1 from furnace control board connected to W1 from thermostat. ( control board will setup 2 stage by timing)

Worst: W1 and W2 jumped from control board connected to W1 from thermostat. You have 2 stage furnace working on high stage only.

Do you have thermostat with W1and W2?
Do you have extra wires to connect W1 and W2?
You have to check the control board switchs

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**Always kill the power ** Hot air rises, but heat will always move from higher to lower temperatures. ** Real man shoot in manual. ** If it ain't grounded, it ain't dead.

tfunk

I do have w2 and w1 on stat, even a Y2. Likely the current Y1 used to connect to w2, but now that's going to the airconditioner. I would need to run another wire for w2. I suppose I could put y to w2 and unhook the aircon for the winter.... Running another wire would probably be a lot of work.

I'll take a look tonight and see what's jumpered and where the other end of my current y1 is going.

tfunk

Seriously, though, there are only three wires from my stat to the furnace what a crapshoot install job back in 2004....

JJboy

Don't use Y wire. Jumper W1 and W2 until you have new cable installed

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__________________

**Always kill the power ** Hot air rises, but heat will always move from higher to lower temperatures. ** Real man shoot in manual. ** If it ain't grounded, it ain't dead.

tfunk

So you recommend the worst of your three options: high fire only? Why is that?

beenthere

The hour is because its not going to high fire like it should, and it sounds like it may be an air flow problem causing a high limit trip, pressure switch, or a problem in the board.

JJboy

It's easy. Best you need new cable. Good you need control board manual

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__________________

**Always kill the power ** Hot air rises, but heat will always move from higher to lower temperatures. ** Real man shoot in manual. ** If it ain't grounded, it ain't dead.

yuri

You can run it properly with 3 wires. R is hot, W is heat and Y is cool. The board knows to turn on the fan for high when AC is called for. G used to be for that but the new boards don't need a G. G allows the fan to run continuos but like I said that is expensive, drafty and wears out the motor. ALL you need to do is find the jumper position on the board that says 1 stage (tstat) and put it there and everything should work unless there is an overheating issue or something else. I don't do PM consulting as too many crazies get upset when they don't get what they want and I have had a few.

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tfunk

W on the stat is connected to w2 on the board....

tfunk

Yeah I can imagine. I just moved w2 wire on board to w, I assume that's where it should be. The blue and yellow wires on the bottom of the board were switched compared to what the manual states so I switched those back, too. See what happens I guess.

tfunk

hmmm, I don't know if I did anything different to it. After making the above change and turned it on at 11:21pm, by 11:31 the burner turned off. Then at 11:33 the blower turned off and it recycled/restarted. Then at 11:51 the burner turned off again 2 minutes later the blower with yet again another restart. So I'm not sure if after the 12 minutes its in high heat and then every 20 minutes after that its just recycling....

beenthere

Look to see if it flashes an error code.

tfunk

That did it. I put a wire on the control board from w2 to w1 and when I turned it back on bam it went on high fire. I have never heard high fire before. The thing has no single stage mode without a wire going to w2. After this cold spell goes away I will wire Y into W2 and same on the control board to try out the two stage capabilities. In the summer I will put it back. Or, we can move our thermostat into the furnace room (it's wireless z-wave, anyway)....

Any last words? Thanks for all the tips thus far.