Rheem Furnance not reaching temperature

[bluemax]

hello,

my problem is this: my furnance runs for about 5 mins and shuts off, it does not reach the set temperature. The only way to get it to turn back on is to turn the temperature down and
back up again and it run about min again and shut off. electronic ignition

thanks for any help on this.

[SeattlePioneer]

Are there diagnostic lights on the circuit board or ignition control signaling a problem? The furnace may be overheating and shutting off on the high temperature limit switch. You'll need a multimeter to check and see if the voltage going to and from the limit switch stays at 24 VAC or goes to zero when the burners shut off.

[bluemax]

ok, ill check for lights and can you give me an idea of where the high temperature limit switch would be.

[paul52446m]

hello,

my problem is this: my furnance runs for about 5 mins and shuts off, it does not reach the set temperature. The only way to get it to turn back on is to turn the temperature down and
back up again and it run about min again and shut off. electronic ignition

thanks for any help on this.

Let get a little more info.
What brand is your furnace?
Is it a 90+ or 80+?
Do you have a drain switch?
Is it a up flow or down flow Furnace?
If when it stops you can turn it down and then back up and it fires
up, i don't think it would be a limit switch.
Is this spark ignition? or glow bar.
Do you have a flame rod?
How old is your unit?
When it stops does the main blower keep going?
When it stops and you turn it down and back up, what happens if you turn it way up , like 80 degrees? Paul

[SeattlePioneer]

ok, ill check for lights and can you give me an idea of where the high temperature limit switch would be.

Usually the limit switch will be above the burners and in the middle of the furnace, and have two wires going to it. Often it will have an "L" stamped on it to identify it as a limit switch and the temperature which causes it to open -- such as "L165". Additional information such as that requested by Paul would be welcome as well.

[bluemax]

little update:

I was able to reset the thermostat through a reset hole. the only thing happens now is that it will reach the set temperature, but it run a few mins shut off and start right back up again
and it would do that until it reaches the set temperature. I can set the temperature at 70 and i would run, but anything past 70 it would not do anything. and i'll get the requested information for you
unit is 12-14 years old

[paul52446m]

little update:

I was able to reset the thermostat through a reset hole. the only thing happens now is that it will reach the set temperature, but it run a few mins shut off and start right back up again
and it would do that until it reaches the set temperature. I can set the temperature at 70 and i would run, but anything past 70 it would not do anything. and i'll get the requested information for you
unit is 12-14 years old

Are you saying that if you turn your stat up to 80 it will not run? If that's the case then turn the stat up to 85 find post W and R Check for 24 volts from post C to R you should have power. Then check for 24 volts from post C to W .
If you power from C to W and furnace is not running, then problem is in the furnace. If you don't have power from C to w with the stat turned way up then the problem is in the stat. Paul

[vivilben]

What would i need for heating a 1500 sq. ft

Hey, do you guys know what size propane gas furnace would i need for heating a 1500 sq. ft. home & what model would you recommend & price..... I heard Rinnai wall furnace is the best.