I have a 10 year old concord furnace. Every year for the last 5 years the computer has gone bad. It went out on 12-23-07 under warranty and still costing big bucks. Before that it went out new years eve and was replaced in January of 07. This time it is less than a month out of warranty. Any suggestions as to why this is happening? I hate to replace a furnace because of a computer but this is ridiculous.

Have you noticed any signs of water that may have leaked onto the board? IF you have an ac coil above furnace, and it is leaking or the drain is plugged(causing it to overflow water and leak), then it would definatley cause this. Give me some more details on your situation. Was the board replaced every time by a tech, or did you do it yourself. You should not have to replace the board this often. Have voltages been checked? Something is causing this. Just need to figure out what it is. Please let me know more on this.

The furnace is a counter flow. The A/C is under the furnace. Every computer has been replaced by a reputable company that has been in business here for 40 years. Well, I did replace one that I bought through the internet. The wait for delivery was just too much.

Last time I spoke to the owner of the company. The repair man took too long and the owner refunded an hour of labor. He told me that he was concerned about the number of boards I had gone through. He was going south for the winter and his son was going to be running the business. He said when he returned he would contact concord/lenox and discuss the issue with them. I never heard back and rarely thought of calling him.

My wife called the repair man and asked to speak with the owner. She was informed that they were all south and would not return until March. They were booked and could not come until tomorrow. Oh, and this is the coldest day of the year here, just at it is in many places.

I can get the thing to run if I turn off all power for 5 to 10 minutes and then turn it back on. Not all board failures have been the same. I think I have 3 old boards here. The one that failed under warranty went back. This one will stay with me too. I am thinking of sending them all to Concord with a nasty letter saying that with this experience I would not buy nor recommend a concord or Lenox furnace or any other of their products.

The board is dry and even relatively clean. No repair man has had a clue as to why is fails. I have wondered if the thermostat could be doing it?

Oh, and one more thing, the model is an 80 Plus.

I would think that maybe it isn't the board this time. If the furnace starts working after you power it down for a few minutes and power it back up, then you may have a different problem. Please let me know exactly what is happening with the operation of furnace. Usually, if a board is bad, the furnace won't work properly at all. You are probably just blaming the board because it has failed so many times(as would most people). I think you should call another tech in to trouble shoot your system. I can try to help, but it will be hard to do through my keyboard. Please let me know what you decide, or if you would like more help on this.

In the past, the board is replaced and it works for a year with no other parts being replaced. Sometimes the error code will indicate a given sensor but given a few days the will totally freak out and quit. This time I am not sure how to extract an error code from history.

This fits Einstein's definition of insanity, doing the same thing over and over again and expecting a different result. I suspect that at $300 or so a pop I could buy a new furnace with about 3 replacement boards.

As for the tech, I don't recall getting the same guy twice so it is nearly always a fresh pair of eyes.

If you provide the number of blinks from the board there is a legend on the back of the blower door so you can post exactly what it says. It is possible that the circuit boards have not all failed and just the act of replacing the board with the wiring being disconnected and reconnected and being moved around could be effecting a cure. Never in my long career have I seen a unit that actually needed more than one circuit board unless there is a problem somewhere else.

You just have to do the math to see where this would just about be impossible for a manufacturer to stay in business with this type of reputation. Your unit has another problem and that problem is leading to the boards being defective or called defective.

The board in your furnace does not like loose power connections, lots of power failures or surges.

Can you estimate the number of power outages that you have had in a year?

Can you estimate the number of thunderstorms that you have in a year?

Did anybody look at the voltage to the furnace? Look for loose connections at the breaker panel and furnace? Did anybody look at how things were grounded? Did anybody measure the voltage across the closed breaker terminals?

Power outages are rare. We do have thunder storms but no evidence of surges. No other appliance has failed. The transformer has been tested. I did pull the ignition cable and reseated it. Since then it has worked. We will have to see if I am up at 3 am playing with it.

One symptom has been the rollout kicking on and nothing happening. Roll out not even shutting off. It is very cold and so the furnace works often. It is located in the center of the one level house so I can hear everything. It just kicked on again and working.

The 64 dollar question is; With the weekend coming, if it works all nigh, do I call the repair man in the morning and tell him not to come? I think it is worth the $100 to have him check it out. Perhaps fix the April air while he is here.

Diagnostic lights are normal. We have seen this and then fail a self test.

Thanks for your ideas. I really expected to see that it was a common problem. I know that some of the computers were bad but it may indeed be that in some cases all that was necessary was to reseat cables and I was sold a bill of goods by a repair man.

I will let you know how it turns out tomorrow.

Thanks again.

Good luck and it might be cheap insurance to have a few spare parts around. I do just in case.

Is your furnace carried by any local suppliers? Are the techs used to working on your brand of furnace. A good tech should be able to trouble shoot any brand of furnace, but this is not always the case. May be time to look into replacing furnace(I hate to say it but), this way you will have a warranty, and parts will be available from installer if you ever have future problems. Just a thought, sounds like you have had a problematic furnace from day one. If the locals can't get er fixed, you are just throwing money away on temp fixes. If you do go with a new furnace, I would suggest going with a company that will be there year round to help during failures. I would love to be able to go south for the winter, but I'm afraid I would be burned at the stake when I returned for the summer. This doesn't sound like a great way to run a business, at least not one such as this. Heating doesn't take a vacation. Or at least not an extened one without someone to cover while its gone(backup heat)

I thank you for your help. I was surprised, they actually covered this under warranty. The tech said he could not find anything for sure except, as I guessed it would, it quit in the night and I awoke to a 57 degree house. Sure didn't want to get out of the shower. He thinks the voltage may be fluctuating but he transformer checked okay.

I had put tape over the switch that detects the cover being removed. In that way it would give the error which caused the failure not the error for removing the cover. It was a circuit board self check failure.

I am thinking of contacting Concord and telling them my story. I don't know why it is always the coldest day of the year. At least three times it was around the holiday. Shoot, I only missed the holiday by a couple weeks this time. If Concord can't or won't give me any satisfaction, I will start pricing a new furnace from someone else. I am only guessing that a new furnace will only cost about a grand. That would be about three service calls.

BTW, I am in Kansas. What part of the country are you in?

Again, I can't thank you enough. It is tough to fix things by long distance.

Glad you got it going again.

I really wish I could be there, but I'm in montana(hard to find a plane here, lol, we just recently got indoor plumbing.) I just don't know what to suggest here. Fix or replace. If you can afford to replace, I would lean toward that solution. If not, I truly hope you can get a competent repair person to cure your problem. However, as I stated before, it sounds like a means to no end, fix it, it works for a while, then fix it again. Just makes for a sleepless night over and over again. Get some sleep, by way of getting a new furnace. We will stay here as long as you. And we will try to help solve your problem. But it will be trial and error, and may cost you more money trying to replace parts that aren't faulty. I just wish you had somebody in your area that could tell you face to face, either,, I can fix this thing, or,, time to bite the bullet and get a new furnace.

You said something ,that you might want to keep in mind,, Lennix seems to be on your bad list,, a lot of others feel the same way,, even though they don`t seem to have a good reputation, but it is only as good as the install,, when or if you are thinking of a new furnace,, keep in mind, have next company look at your duct system to be insured that it is installed right and is what your house needs,, sometimes a supply and return system is wrong for the house and is ruff on the furnace ./maybe overworking it in some way