BSC

I have a Comfortmaker RPJ2 that was installed new in 1996. Recently it has begun to give problems: the burner will ignite, burn about 5 - 10 seconds and then go out. It will continue this cycle until it is powered down, either at the thermostat or the disconnect for a minimum of about 45 minutes. It will then function properly for one or two cycles then begin with the previous problem again. I think I have ruled out the thermostat itself as a problem by switching thermostats between the upstairs and downstairs units with no negative effects on the other unit. I have an original parts list that I could refer to if anyone has any ideas as to the cause of this problem.
Thank you for your help.

drpsr69

You need to have someone look at your furnace that knows what they are doing.They have to trace the problem to a individual component with a meter to tell what is wrong. You or anyone can guess but a good tech can find the problem without being a parts changer.

donze

This is similar to the problem I have begun experiencing with my Comfortmaker RPJ II, with the following differences/observations:

The Furnance will cycle through this for a while, sometimes it will kick in and work properly for days at a time, sometimes it will simply not work, no matter what I try do with regards to the power cycle etc., and then after a day or so, it will kick in and work as it should.

Sometimes, if I just take the cover off to observe it, it begins to work, other times not.

I did notice that the diagnostic lights flash 6 times then repeat the cycle. The current controller (The General by Inter-City Products, p/n 50A50-112) has a label that states that it should only flash 1 - 5 times, so this is baffling as the code "doesn't exist".

I had to replace the igniter about 2 - 3 years ago. The ComfortMaker was installed in the early 90's and had had no other problems that I know of. (We bought the house in '94)

I would really appreciate any help and guidance.

Bjd

Kinda of hard from up here to tell whats going on in that furnace, but in your replys you stated that if you left the unit cool down it would operate fine for a few cycles. This alone to me sounds like either a roll out or a spill switch.
In either case you will have to locate the switch and find out why it has tripped out.

There always is a reason for them to trip, you may have bigger problems than what may seem as a small switch.

Bernie

Unregistered

I had the exact same problem with my furnace this past winter. The solution to this problem was that I had to clean the thermocoupler. It is a rod that is in from of the burner to the far left. It was dirty and couldn't register the heat of the flame, causing the the flame to go out after about 5-10 seconds. You can clean it by taking it out and using sand paper on it for a minute or two. If this doesn't work you may need to replace it. They're not too expensive. I hope I this helps.

wilroy

My RPJ2 will not even ignite any ideas???
On the control unit it flashes 3 times - What does than mean?

Digitalsine

The code means:

Pressure Switch Contacts are open

( Switches sense pressure, vacuum or differential pressure in applications including fan status, dirty filter monitoring, or frost build-up on coils.)

Here's a sample of what one may look like:

Sorry I can't be of more help, I only know what it is and what it means, but I have no idea on how to fix it. You can call a contractor and let them know of the code. They will surely be able to fix you up. :Thumbs:

adamsmrbig

anyone have a wiring diagram they could email me on this furnace. i would really appreciate it.

mdshunk

What happened to yours? Should be pasted on the inside of the lower cover.

sbrand

Hi: I'm dealing with a Comfortmaker RPJ II that works sporadically. I have to flip the switch to start it even though the thermostat is set 10-20 degrees higher than the temperature reading. The furnace will ignite, blow hot air for a few minutes, then shut down, rarely reaching the desired temperature. I reach the temperature set on the thermostat occasionally although this is rare when the outside temperature is extremely cold....

Suggestions and advice are encouraged and welcomed.

service fitter

the first guy seems like the flame sensor is dirty , you can take it out and clean it with a steel wool , it looks like a metal stick in front of the burner, usually its held in by one screw and has one wire off the back , make sure the power is off, the sensor has 120 volts .
the last guy sounds like you have a airflow problem , could be a dirty filter ,a dirty coil , to many closed registers ,furniture in front of your returns , or duct work to small , its hard to tell off the computer , but thats what it sounds like to me

service fitter

the guy with the pressure switch, these switches usualy dont go bad , the number 1 cause of them opening is a blockage of the flue or pvc exaust , i have found ,dead birds, nest, nuts from squirels ,in pvc ive found leaves, rocks from kids and sagging pipes that closed from condensate , the number 2 cause is a negative pressure in your house, I had a retirement home where a unit kept going off on the pressure switch , and for about two weeks we couldnt figure it out, finally I found a missing brick behind the furnace , that led to a chase down to the parking garage , everytime the garage opened the exaust fan would kick on and shut down the furnace .

dlfrand

The house I'm working on has a 50A50-112 controller. on a Comfortmaker Model GUI100A016BIN. This furnace/ac unit will just quit working intermitantly, both summer and winter. I have found that if I go up and wiggle the 12 pin connector on the front of the control module it will start working again and I can duplicate the problem by wiggling that connect. the people have had a HVAC company out and the suggest a new furnace. This seems a drastic measure for this problem, Any suggetions, does it need a new board or a new furnace. This furnace/AC is installed in the attic and goes through drastic tempature changes between summer and winter. I imagine this cannot be to good for the unit. Any Ideas?

imajwood

Check the flame sensor! Wipe the film of dust off and bill your minimum!

arthurh

Just relized age of this thred, sorry for the incovince have moved my question to new location on this site
thanks art

vtxman

The sand paper worked. yah!


Thank you.