Pilot Lights and Thermal Couplers

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    • #278086
      Avatar photoAnonymous

        I have owned an old house for three years; during that time and in the one year prior, the gas furnace thermal coupler has been replaced three times. Once again the pilot light fails to stay lighted. I can probably spend another $140 to have another coupler installed, but what keeps causing it to fail? Is there something else that will fix the problem (more) permanently? Thanks

      • #297665
        Avatar photofourth year
        Participant

          Is it a thermocouple or a thermopile? $140 is too much for a thermocouple and if it is a thermopile, loosening the screws and then retightening them usually cures the situation.

        • #297666
          Avatar photoBenPeirce
          Participant

            Actually, it is a thermocoupler. In the past, it always seemed to go out on, say, a saturday night, so I had to pay premium service rates.

            I learned to replace the coupler myself – a US$5 part – but that did not fix it this time. I still haven’t called a pro. Thoughts? Thanks

          • #297667
            Avatar photoSylvanLMP
            Participant

              You know it never seems to amaze me how stupid some “employee” lack of mentality can be.

              Here you are the consumer not complaining about the actual price of the repair BUT what can be done to get more longevity out of this condition.

              This “Helpers” lack of mentality is one of the major reasons the new comers into this one time profession are now getting STUMBLE BUM pay.

              Only a bonifide idiot would say $$$ is to high to pay.

              I personally AGREE that the HELPER/Apprentices should have NO benefits Or should NEVER EVER be paid more then minimum wages.

              I feel the franchises are correct that a “plumber” can be trained in 12 weeks as why spend more for educaton?

              For arguments sake lets say a legitimate plumber has a business and pays upwards of $40,000 per year for insurance and Has REAL mechanics (NOT stumblebum helpers) that get in the “envelope” $45 per HR PLUS benefits like hospitalization, paid vacations, union check off for IDIOT training programs (that are now proven failures)

              And lets suppose this Plumbing contractor has a fully stocked van and this van has a driver and uses gas and has insurance and this van cost MONEY to buy — operate — and Maintain.

              Lets forget the training costs to tech a brain dead loss leader HELPER to learn to keep their mouth shut on topics they have no idea what they are talking about.

              I am sure the plumber who replaced the thermo couple has a phone THIS phone cost money.

              I would imagine this plumber has at least one person answering the phone, this phone person also likes to get paid.

              Of course the plumber used his BARE HANDS to remove this thermo couple and NOT any tools as tools cost money and why should tools be figured as part as over head.

              The knowledge to remove the thermo coupling came FREE as ANYONE can do it… no training or skills required in a helps mind.

              This helpers lack of gray matter is the reason I only have full fledged mechanics working for me as I cannot tolerate stupidity in the field.

              Apprentices are NOT ALLOWED to work by themselves the ruling should also be they should be gagged before they are let out of the cage.

              The price you paid to have a Qualified journeyman come out was CHEAP knowing you also had him/ her check your flue for spillage and possibly adjust your flame to a slightly lower setting so it wont burn out this couple.

              It could also be the environment that causes this like bleach or other chemicals present.

              What you did pay was what most Qualified plumbers would charge for regular time if not more.

              Suppose this helper took into consideration traveling time AFTER all these HELPERS do like getting paid traveling to each job UNLESS of course these folks are only paid for PRODUCTIVE work by the actual work order.

              I just hired another Licensed Master to install a wire from a water meter to a remote censor as I am too backed up in work to get there.

              His price for 8 feet of bell wire installed in less than 20 minutes of actual work came to $270 and I was thankful he was able to get there even though it took his men over 1 hour stuck in traffic.

              Amazing how employees think the boss makes TOO MUCH for a simple job BUT if the boss said “Hey helper today you only swept the shop ILL pay you $5.00 as IT WAS A SIMPLE job ILL bet then it would be another story.

              I am able to bill OVER $225 per HR for ONE MAN (LABOR) yet I personally don’t think its enough considering there are only 1,200 Licensed master plumbers in NYC and over 50,000 Lawyers who make more then the chump change I make.

              Personally I think you should ONLY hire NON UNION plumbers as why should you the consumer have to be forced paying for a union apprentice getting an education off your back?

              An apprentice is USELESS to you as they cannot do the job they are there to learn and YOU pay for this wasted time carrying their employment

              An apprentice is not needed when doing simple tasks so why should the employer pay these leaches for non billable time?

              Next time instead of hiring ANY UNION plumbing contractor CALL SEARS or another gas appliance firm who can work much cheaper.

              Actually I think the Gas UTILITIES should service all gas fired appliances as they can do it much cheaper and better as they only HIRE skilled craftmen.

              I am sure the union mechanics get way too much money why have an apprenticeship?

              If the folks don’t know the trade don’t hire them..

              Lots of big city schools have plumbing classes, get trade school kid to do this kind of work CHEAPER then the union NON qualified helpers.

              Actually your better off asking to see the masters license and if they are not the owner himself DON’T allow them in your home.

              Think of the LMP as a doctor and the apprentice as the bed pan jockey as that is all an apprentice is legally allowed to do is clean up after his mechanic and possibly get the coffee if they don’t screw that up also.

              Why not contact the manufacturer and mail them copies of the bills you paid and see if they will give you the name of a factory authorized repairman.

            • #297668
              Avatar photoGuest
              Participant

                Ben: All thermocouples are not created equal. Some mickey Mouse
                imports can be had for $3.98, and are not worth the powder to blow them back to China.
                Some cheapo thermocouples have a
                tough time delivering 120 milivolts with a good pilot flame. The better quality domesticly manufactured thermocouples can produce 300+ Milivolts with only a marginal pilot burner assembly.
                It is the voltage developed by the thermocouple that holds the main valve open and keeps the heater on line. If insufficient energy is provided by a bargain basement thermocople, the magnet that holds the solenoid core up will drop the core and the main gas
                valve will shut down.
                If you enjoy the roll of Mr. Fixit more than a steady supply of
                hot water..knock yourself out. If you really expect a qualified gas
                serviceman to schlep over to your place to fix your heater, you may have a beard down to your knees.
                The qualified Gas Contractor has
                earned his right to a fair price for his services from years of work
                and schooling. He also carries explosion and collapse insurance in
                the off chance that something might
                go BOOM.
                Most thinking Gas Contractors hesitate to offer suggestions to the Do-it-your-selfers.Because the Law suits and Litigation that can
                follow an explosion can be really grim.
                Bud

              • #297669
                Avatar photoSylvanLMP
                Participant

                  Bud it wasn’t Ben who had a problem with the price it was a “HELPER” mentality or lack of that questioned the price.

                  Ben just wanted to have the unit working properly after investing money several times for repairs

                  You see Bud in a helpers/ apprentice PEA sized BRAIN they think if a contractor charges $140 its ALL PROFIT

                  They think the union training they get doesn’t cost CONTRACTORS money.

                  The office space is FREE and so is insurance.

                  Ben NEVER questioned the bill just the fact this couple keeps failing.

                  The Pea Brain Whiz kid thought it sounded high priced as the plumber making the repair lives across the street and he walked to the job.

                  The liability of working on gas is NIL and thus the contractor is entitled to NIL for profit.

                  We contractors UNLIKE other fields are doing plumbing for a hobby not as our livelihood and we should actually pay journeymen no more then $7 per HR and ONLY for the actual time spent on the job.

                  Bud thankfully this consumer knows the TRUE cost of doing business and why I must say again the apprentice program should be dropped as IT IS NOT WORKING by looking at the caliper of mentality that is being turned loose on the unsuspecting society.

                  If folks want to be plumbers or go into any trade LET THEM PAY for the education JUST LIKE any other professional field.

                  Why should contractors be forced to foot the bill for stumble bums helpers for 5 years? Why pass this on to the poor clients?

                  Think of it WHO pays a doctor to go to medical school? Who pays a Lawyer to go to school?

                  Why should the unemployable bums know nothings of society get paid to learn a trade?

                  When a person PAYS for their education then it means something UNTIL then the education is wasted and taken for granted

                  The trades are filled with too many flunkies and that is why we are now having to resort to simpleton plumbing systems. AAV and plastic for example

                  The Do it yourselfer is MUCH better going to a home center then allowing a helper dabble in their home.

                  Hopefully the utilities will handle all repairs as well as major chain stores as they HIRE SKILLED craftsmen not wasting money training the UN trainables with money wasting trainee programs.

                  Years ago apprenticeship programs meant the apprentice PAID for the education today we have the GIVE ME mentality and not pay the boss as he is only taking all the risks GOOD UNION Mentality

                  I now see why American companies are setting up factories over seas.

                • #297670
                  Avatar photoArt_xyz
                  Participant

                    Bud,

                    I don’t know any thermocouples that put out 50 milivolts let alone 120.

                    Art

                  • #297671
                    Avatar photoGuest
                    Participant

                      Art: I concede..My numbers are not
                      correcto mundo on the mv rating of
                      thermocouples. I even fired up my torch an checked it out with a LCD-
                      VOM. The best I could do with a no name Generic 18″ fits all was 36 mv…Penn Basso 56 mv..Honeywell did some better with right at 60.
                      I think part of the problems are due to the unseen voltage drop that occurs while the solenoid coil is connected across the output of the thermocouple. It is possible that my ancient memory was thinking Miliamps instead of
                      milivolts.
                      At any rate..thank you for your
                      observation.
                      There is a substantial difference in the performence curve from the manufaturers that show a spec. sheet rating for thier product as
                      opposed to mass marketed poor quality replacement items.

                      Bud..Suncoast Plumbing Inc.
                      Sunny Florida

                    • #297672
                      Avatar photoGuest
                      Participant

                        Bud,
                        Thermocouples 30-60 millivolts satic 15-45 millivolts working most valves will hold down to 6-8 Millivolts
                        Thermopile 300-600 millivolts static 200-450 working less that 150 and most valves will not hold

                        Pile coming from piles of thermocouples (about ten in one head)

                        To Ben’s Question why
                        well it may or may not be the thermocouple below is just some of what it could be.
                        1)Pilot flame
                        first you need to check that the pilot is on(lit)has it a correct size and flame pattern and is playing the thermocouple in the right place there is a hot and a cold spot on a thermocouple and it will not work if the cold spot is heated or the hot spot cold
                        2)Thermocouple may not be given right voltage
                        3)magnetic valve faulty
                        4)contacts could be dirty stoping voltage
                        5)interlock like The E.C.O. may have failed or operated
                        6)pilot flame may blow out from the main burner lighting or turning off (pilot in wrong place)
                        7,8,9……. and so on and on

                        GET A SECOND LICENCED GASMAN TO CHECK IT OUT

                        If he doesn’t have his volt meter and his gas pressure meter in hand
                        as part of his kit hes not the one you want ( and for the benifit of Sylvan anf the 4th year if the gasman knows his job he’ll charge well too you wouldn’t want a Heart surgon that just charge a regular house call fee WOULD YOU?????)

                        “Buyer beware” and “You get what you pay for” apply here

                        Well you got my to bits worth

                        Rgds to you all

                        Michael the gasman
                        http://www.burngas.com

                      • #297673
                        Avatar photoGuest
                        Participant

                          BenPierce
                          Listen to Michael the Gasman’s advice! A serviceperson worth his salt will know to look for these things and how to check and adjust them. Pilot burners rarely get cleaned and adjusted properly, especially on a saturday night. Plan ahead and have your equipment cleaned and serviced at least once a year by a qualified service contractor that you trust. It won’t eliminate all nuisance problems but it’ll surely minimize them and you can sleep well at night knowing your equipment is safe!

                        • #297674
                          Avatar photorobala
                          Participant

                            Sylvan, I would like to meet you face to face. You are a real “dandy”!

                          • #297675
                            Avatar photoGuest
                            Participant

                              To paraphrase Dan Holohan, “If you keep changing the Thermocouple and it don’t solve the problem, then the propblem ain’t the Thermocouple!
                              It it time to look at the gas valve as the culprit. The thermocouple controls the gas valve but if either goes bad the symptoms are similar. I would replace the gas valve, adjust the pilot, chck the gas pressure and make certain that the thermocouple is properly impinged by the flame.

                            • #297676
                              Avatar photoArt_xyz
                              Participant

                                to paulplumb:

                                The sign of a true mechanic is someone who just starts replacing parts because they lack the knowledge to properly diagnose the problem.

                                art

                              • #297677
                                Avatar photoHarold Kestenholz
                                Participant

                                  art, ther are at least four stages of mechanical knowledge.

                                  1. The person guesses the solution by replacing parts until it appears to be solved.

                                  2. The serviceperson follows a procedure documented by a training organization or a manufacturer.

                                  3. The serviceperson is able to follow the troubleshooting procedure based upon experience and knows the parts recommended in the manufacturer’s handbook. This mechanic can repair modern equipment.

                                  4. The serviceperson has enough experience to troubleshoot using procedure ingrained by experience and has the knowledge to substitute parts made by other manufacturers to make the appliance operate safely. This person can repair out-of-date or obsolete appliances and takes a higher risk by doing so.

                                  These four stages in abilities are accumulated by a serviceperson over some years, if and only if the person has the personal intelligent ability to learn to the limits of his dedication.

                                • #297678
                                  Avatar photoGuest
                                  Participant

                                    I am a gasfitter by trade from Vancouver,B.C. Sounds to me like the problem is in the pilot orifice. If you don’t like gas, call a tech. If you feel comfortable, remove the pilot tube at the pilot burner, remove the orifice from inside the pilot burner, and clean it out well. Sometimes sulphur in the gas can plug the orifice, causing a small flame to to burn over the thermocouple. A small flame cannot heat up the thermocouple enough to generate the electricity required to operate the electromagnet in the valve. Problem Solved.

                                    Sincerely Jason.(a young buteducated and witty gas tech.)

                                  • #297679
                                    Avatar photojb
                                    Participant

                                      Ben when the service tech replaced the thermocouple in the pass did he clean the pilot or just change thermocouple..you may have a dirty pilot orfice or the pilot itself could be warping and turning away from the thermocouple.

                                    • #297680
                                      Avatar photoGuest
                                      Participant

                                        I’ve got a boiler that just won’t light lately, and I think it’s almost certainly the pilot flame not right as the brass nozzle is cracked. Thanks for the informed suggestions guys.

                                      • #297681
                                        Avatar photoDP
                                        Participant

                                          All above made interesting reading. Some of it was eye opener, some I learnt from.
                                          I am a qualified gas fitter (British). I have to sit exams every five years to keep me qualified to carry out work under the CORGI banner. Not to be CORGI registered could land me in court. Thinking about it, doing something silly would still land me in court.
                                          CORGI Inspector check my work once a year as well.

                                          Regarding the question of thermocouple. It is a loop circuit compring pilot flame, megnetocoil and thermocouple. All sorts of scenarios have been posted but what has not been mentioned is that if the inlet gas pressure was low, and other gas appliances were served off the same gas line, on full load the pilot will extinguish due to the filter fitted in the gas valve.
                                          To change a gas valve, or a thermocouple without proper diagnosis is both time wasting and unsatisfactory work practice.
                                          Sit back and observe. See what is happening before getting the tools out and form an opinion. Then carry out the repair. The result will be that you will have cleared the fault on first call AND customer will recomend you to their friends.
                                          To be a qualified gasman or to be working for a Utility does not lead to full ability to fault clearing; it is a common practice to not use the brain but the parts to clear faults- be it gas or whatever.

                                        • #297682
                                          Avatar photoDP
                                          Participant

                                            All above made interesting reading. Some of it was eye opener, some I learnt from.
                                            I am a qualified gas fitter (British). I have to sit exams every five years to keep me qualified to carry out work under the CORGI banner. Not to be CORGI registered could land me in court. Thinking about it, doing something silly would still land me in court.
                                            CORGI Inspector check my work once a year as well.

                                            Regarding the question of thermocouple. It is a loop circuit compring pilot flame, megnetocoil and thermocouple. All sorts of scenarios have been posted but what has not been mentioned is that if the inlet gas pressure was low, and other gas appliances were served off the same gas line, on full load the pilot will extinguish due to the filter fitted in the gas valve.
                                            To change a gas valve, or a thermocouple without proper diagnosis is both time wasting and unsatisfactory work practice.
                                            Sit back and observe. See what is happening before getting the tools out and form an opinion. Then carry out the repair. The result will be that you will have cleared the fault on first call AND customer will recomend you to their friends.
                                            To be a qualified gasman or to be working for a Utility does not lead to full ability to fault clearing; it is a common practice to not use the brain but the parts to clear faults- be it gas or whatever.

                                          • #297683
                                            Avatar photoGuest
                                            Participant

                                              how do you test the millivols on a thermocouple?

                                            • #297684
                                              Avatar photoGuest
                                              Participant
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