DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (http://www.diychatroom.com/)
-   HVAC (http://www.diychatroom.com/f17/)
-   -   This may help someone with carrier ignition problems (http://www.diychatroom.com/f17/may-help-someone-carrier-ignition-problems-5809/)

AweMan 01-08-2007 07:02 PM

This may help someone with carrier ignition problems
 
I have a carrier model 58st a070 012.
Recently I experianced ignition problems, I called out a service technition, an $80.00 service charge just to come look. He said that the limit switch had gone bad {the one just above the combustion chamber} I replaced it at a cost of $25.00 but NO CIGAR, the problem of no ignition presisted. Once again I called him back {another $80.00 later he said the igniter was bad I replaced it at a cost of $40.00, again NO CIGAR. Tired of the $80.00 housecall fees I did something most people that don`t know anything about HVAC would dare to do. I turned up the gas pressure on the gas valve only to find I did get ignition BUT a new problem arrises, flame rollout, excessive gas was overheating my NEW limit switch and causing it to open. Thus shutting down the burners. They would cool and the system would reignite again. I knew this wasn`t a good thing so I turned the gas pressure back to the spot I had marked on the valve body just in case I needed to go back to square one. Hence I was back to the original problem of No ignition {one tube would light but not the other two} Then I read about cleaning the flame sensor in one of these forums, I did that But still No ignition I also cleaned the gas orifices on the tube coming from the gas valve, Still no ignition. when I had the gas valve assembly off I noticed a slight coating of dust inside the barrels of what { for the sake of not knowing the terminology I will call the gas manifold} It`s the plate that the ignition module and flame sensor is attached to, the gas valve blows gas through it into the combustion chambers I removed this manifold and used soap and water and a bottle brush to clean it spotless, on the side closest to the combustion chambers there is a slot connecting each of three barrels together this slot allows the ignitor to ignite the gas present in them hence igniting all three chambers. I cleaned it out with an old toothbrush. Then I reassembled the ignitor making sure it was on a 90 degree angle to the manifold and re assembled the flame sensor after I cleaned it with fine sandpaper making sure it was centered in the thrid barrel. I reassembeld the manifold in my unit and reinstalled my gas valve hooked up all the wires { ignitor plug and flame sensor} turned the gas on and turned the power to the furnace on. The fan began to whirr as usual then it stopped and gas began coming out of the valve after a short time the ignition sensor began to glow and lo and behold ignition at last! The morral to this story is: A little {very little} dust cost me $225.00
But a valuable lesson at that
I hope this post will save someone else that $225.00 or more:thumbup: NOTE: If you remove the ignitor be very careful it is very fragile if you break it your furnace will not ignite until you replace it. If you need to bend the bracket to get a 90 degree angle remove the ignitor from the bracket before you attempt bending it.

trollmastergeneral 01-08-2007 07:33 PM

Well I will say one thing the guy who charged you a second time must have had oversized kahonies to charge you a second time. Most companies dont charge for going back.:no: Everyone has made mistakes but charging is not right.:eek:

AweMan 01-09-2007 12:35 AM

Ripped off
 
Yes I pretty much felt ripped off! Especially when I realised that there was no need for new parts at all! I have sence replaced the new parts with the old ones just to see if they were faulty {they were not!} I will run the original parts until they fail sence I already have replacements on hand. One thing I realise is clean everything possible up beofre you contact a service rep, change the filters, make sure the vents both intake and exaust are clear, and parts you can easily remove wash with soap and water providing they are not electrical parts, vacume off all the dirt/dust you can see. make sure all eletrical connections are secure and not corroded. And lastly but not leastly reasearch your problem on these forums, most likely someone has had simular problems and can help you form a solution. Taking time to take these steps could save you from a rippoff artist.

#CARRIERMAN 01-09-2007 09:43 AM

Hi AweMan

I hate to see this happen to people, but poor burner maintenance will cause multiple problems. A good service tech would have given you all the possibilitys, not just a few of the surface pobabilitys. I am happy that you had a good outcome, as trollmaster said what a pair.

Thank you
Rusty

ajawnyj 05-13-2008 10:57 AM

same problem
 
AweMan
I purchase my house new in 2002 and your problems seem VERY similar to mine. My burners were not igniting as well. The technician replaced what you called gas manifold. He claims there wasn't sufficient space to allow gas to travel for ignition. He also turned up the gas. I too started to notice the same problems from that day on and thought I put in an incorrect evap. coil restricting the aiflow. The unit will run and then burners will shut down before the house reached temp. Not knowing how much he turned up the gas, I am not sure if I should turn down the gas a little at a time. This leads me to my main question, how dow I turn down the gas flow? What is flame rollout? Thanks.

AweMan 05-15-2008 10:55 AM

Quote:

Originally Posted by ajawnyj (Post 122910)
AweMan
I purchase my house new in 2002 and your problems seem VERY similar to mine. My burners were not igniting as well. The technician replaced what you called gas manifold. He claims there wasn't sufficient space to allow gas to travel for ignition. He also turned up the gas. I too started to notice the same problems from that day on and thought I put in an incorrect evap. coil restricting the aiflow. The unit will run and then burners will shut down before the house reached temp. Not knowing how much he turned up the gas, I am not sure if I should turn down the gas a little at a time. This leads me to my main question, how dow I turn down the gas flow? What is flame rollout? Thanks.

Flame rollout Is too much gas flow, when ignited will overheat your flame sensor in turn shutting down the gas,
Turning down thew gas:
on the left hand lower side of the gas control unit you will see a brass screw, remove it. Inside there will be another screw Turn it counter clockwise to reduce gas flow and clockwise to increase.
Preceede in very small incraments until the ignition is consistant and Overheating the flame sensor does not occour. Eg. flame rollout

As I stated in my original post ANY dust in the gas manifold distribution slot
Will cause inconsistant ignition.

Deffinition:
gas manifold distribution slot {For the lack of knowing the correct termanology} on the gas manifold, the side facing the combustion chamber. where the gas goes into the combustion chambers there is a small slot connecting all three tubes, this slot MUST BE clean of any and all obstructions no matter how small.
I hope this helps clarify, and possibly someone with more HVAC knoledge than me can relate more info for you.

ajawnyj 05-15-2008 02:20 PM

Thanks for the reply. I turned the gas down and bam, running perfect. No more LOUD ignitions, ignites the first time and MUCH quieter.

On my unit the installation manual was the opposite, ccw to decrease flow and cw to increase. It only took 4 years of frustration :furious: and a tech who arbitrarily turned up my flow to mess everything up. I will eventually hook up a manometer to the gas valve to make sure I have the correct pressure. It's evident that it was not set correctly. I wonder how many other houses this guy fixed.

Thanks again.

8 Ball 05-17-2008 07:15 AM

I hope this does not encourage people to start adjusting things on thier furnaces at the first sign of trouble.Gas pressure adjustments are thing that can have disasterous effects when done without the proper instruments.

Typicaly a pilot tube runner allows the flow of gas between the burners to ignite the burners almost simultaneously. When dirty or restricted, it does not allow fuel to "run" from one burner to the next..Delayed Ignition.

Flame roll out is when the ignited fuel comes out of the front of the heat exchanger, after the burners ignite.

Both conditions are very serious, but thier cause is NOT soley due to gas pressure.

Some lawyers are incompetent also...and charge more!

ajawnyj 05-17-2008 08:28 PM

8 Ball,

I hope it doesn't encourage anyone do adjust their gas pressure either, but it is certaintly strange that a technican turned up my pressure without a meter. And I didn't start adjusting at the first sign of trouble. I called a technician and he's the one that started messing with the gas pressure. I thought these were proffessionals? If anthing, I made it SAFER. Too much gas = too hot of a flame which triggered my limit. I'm pretty damn technical and not just your average DIY'er. I will hook up a manometer. Heck, I may even make my own which is really simple:thumbup:. Here is a link to measure in units of inches of water.

http://www.rverscorner.com/manometer.html

Did this in college and at work.

8 Ball 05-18-2008 07:06 AM

Thank you for the link, if I could I would forward it to the service tech that came to your home, sounds like he needs it more than we do.

I must ask if you called the service company back to report his actions. Owners need to know if thier techs are incompetent, and without feedback from customers and coworkers, they may never know.

My next concern is that you said this problem went on for four years. Excessive gas in a furnace leaves a residue, soot , unburned carbon that attaches itself to everything and coats the inside of the heat exchanger, inhibiting heat transfer. If you have a high efficiency furnace, you may need to have you secondary heat exchanger inspected, along with the primary.

In the owners manual you will also find the correct MANIFOLD pressure for your furnace.

Service Companies cant stay in buisness with unhappy customers. Call them and have them make it right to your satisfaction.

Knucklez 05-20-2008 09:57 PM

great thread,

great advice from pro 8-ball :)

SlightlyHandy 02-08-2009 10:47 PM

I had the same problem with my carrier furnace. The first tube would light, but the rest wouldn't (most of the time). I called BelRed HVAC to come out and service the unit. It worked for 3 weeks, then started acting up again. I called BelRed again to come out for a diagnosis. The guy spent 5 minutes listening to my story, then said i needed a new thermostat, luckily he had one in the truck for the low price of 300 bucks! How lucky, i said no thanks. He said if that didn't do it, he'd replace the circuit board for 500 more bucks. I told him to get out...but only after i cut him a check for the 'diagnosis' work. I found this blog 10 minutes after he left, disasembled the burner unit and cleaded the pipes per the suggestions above. Put it back together and BOOM, all 5 pipes fired instantly as they should. Been working all night. I think there was some dirt in the 'slit' that runs between the tubes. I cleaned it out with a soft metal brush. SO, moral of the story, HVAC 'pros' are jack artists for the most part, and I haven't met one i can trust yet, barring the helpful folks on this blog and others like it. Thank you for all your help! I have no experience with HVAC but did what the pro's refused to do or couldnt do, in 30 minutes, for $0.

beenthere 02-09-2009 06:56 AM

Unfortunately.

The term "Pro" only means that someone gets paid for what they do.

It has no bearing on how good he is, or how is ethics or morals are.

In the sense of what "Pro" is thought to mean.

A real "Pro" would never confuse/claim a thermostat is the cause of the flames not crossing over(the slits are called cross overs).

What both you, and the OP had. Was a guy that charges a fee to come out and guess at what is wrong.

A real service tech(proficent in his skills and abilities), brings in testers, and meters to find the cause of the problem.

A guy that slaps on multiple parts and keeps saying if this doesn't work then you'll need this that and the other thing also changed out, and if they don't work you'll need a new furnace, is a servce hack.

DangerMouse 02-09-2009 07:35 AM

sounds like the wife's car. it kept kicking in the anti-theft system and not allowing her to start the car. we paid over $1,000 to have new this and then new that all the way to the new ignition and it did not stop. the trick none of the service guys would tell her is to turn it on for ten minutes, then restart. that worked when it did it a couple more times. now it has not done it for 2 years. ???? no-one ever found the problem. i gotta get her a new car, but i'm thinking i'll get her an old classic in excellent shape and avoid all the computer crap. (my truck is a 72)

DM

hvac122 02-09-2009 11:59 AM

It could be that I am reading this wrong but it sounds to me like the op just wanted to pay for diagnostics and then replaced the parts himself? If it was my company there would not have been any warranty for the second trip either. It could be that the limit was tripped and after replacement something else was also wrong.

I think that some of you are throwing this tech under the bus with only hearing one side of the equation.


All times are GMT -5. The time now is 09:54 PM.


Copyright 2003-2014 Escalate Media LP. All Rights Reserved