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Weil Mclain gv-5 ignition problems

tim smith
tim smith Member Posts: 2,749
will probably find a lot of debris in it. Heat exchanger scales up on these boilers after 10 yrs or so when on lower temp systems. We have split numerous GVs and brushed and scraped to clean up. Order new section gasket kits, (fairly expensive for gaskets :) This is a most of day at least job to get cleaned up and back together. If evident things like igniter probs, pressure switch probs etc are not causing it, usually this is the culprit as far as we have seen on nuisance trips. Tim

Comments

  • Jeff_134
    Jeff_134 Member Posts: 1
    ignition problems

    I have a weil mclain gv-5 boiler. Lately it has been having ignition problems. The unit will start its ignition cycle, but there will be no flame. The unit will cycle a few more times to try it, then just shut down and the 'power" and 'flame" LED will flash constantly. I can turn the unit off, let it rest a few minutes and then 99% of the time the unit will fire up. However, sooner or later it does the whole thing all over again. My repair guy cleaned the igniter and checked the unit out, but basically tells me it is old and needs replaced. I dont really buy that. Seems like there must be some solution??
  • Steve M_2
    Steve M_2 Member Posts: 121
    Cleaned the ignitor?

    Did the tech even break out and use his volt/ohm meter? If not, you need to get a competent service guy to work on this. The problem I've found with these units is the combustion chamber gets debri flying around and it interfers with the flame rectrifcation. A real tech would order the gasket kit you need to service this unit and do a good cleaning. You need to removed the combustion blower to clean the chamber and also clean the condensate trap.

    After him cleaning the ignitor, you're probably going to have to replace that soon. It's ceramic and the only cleaning it needs, is to blow it off. Did he even check the ohms of the ignitior? I'd love to sell you a new boiler as well but you have to at least do the basics and try to get the thing running to prove your worth as a service tech.

    I would call the company back and ask to talk to the service manager and get someone back that knows what they're doing or find another company. Anyone that attempts to sell you you a new boiler because it's old is dishonest or lazy or both. Hope I haven't been too harsh.
  • Darrell_4
    Darrell_4 Member Posts: 79


    You cannot clean the ignitor on a GV boiler...it is carbide...you either replace or you don't.

    Replace the ignitor as a matter of course. That solves a number of nagging little problems. small cracks will prove with a circuit/ohm tester and fail to ignite the gas. Ot they will work and then not work. It is not expensive...change it.

    If that fails, get a good, reputable tech to pull and clean the burner cone.

    If you do not have the current upgrade control board, get it.

    You could also be having problems proving the airflow...that is more technical but certainly not expensive or out of the ordinary for a good tech.

    The GV is extremely reliable and easy to work on. There is no justification for replacing the boiler unless it has been abused.

    There may be sufficient justification for replacing your serviceman...
  • Mike Thomas_2
    Mike Thomas_2 Member Posts: 109
    Bullet Proof

    I installed lots of GV5's. Replaced a few boards, due to voltage surges, and an odd ignitor or two, but they are still a good boiler. Others are correct, you don't clean an ignitor....
  • EricAune
    EricAune Member Posts: 432


    GV5's are great boilers.

    All of the above recommendations are right on. Maybe have the gas pressure checked as well.

    Peace

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  • Marc_23
    Marc_23 Member Posts: 2
    cleaning?

    I am wondering how you clean the GV without completely dis assembling the sections? Is that why you suggested the gasket kit?

    Marc
  • Darrell_4
    Darrell_4 Member Posts: 79


    You cannot clean the sections on a GV boiler without splitting the sections. Then only ones I've had to clean were abused by cold shocking them radiant system and no return temp protection. It makes them sweat inside and rust.

    The gasket he was referring to is the fiber gasket between the blower assembly and the burner mount. I can usually save it for reuse...but a new one is a good idea. You can use a hi-temp silicone instead but do not insulate the burner cone from the section block...it has to have a good ground pathway.
  • Mitch_6
    Mitch_6 Member Posts: 549
    What type of flue pip do you have

    Some older model GV's had plastic venting that is in recall. You should be venting in stainless. The GV's are known to plug over time. and need to be cleaned the best as possible.

    Some of the early GV's have a bypass valve that sticks reducing temperature output. I doubt this is causing your ignition problem.

    Myself I am a fan on good old gravity venting cast iron boilers or I go strait to mod con's. Sealed cast iron always seems to be a compromise and a pain to service.

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  • spiders

    on all the gv's i have seen with intermittent ignition failure the number one cause has been a spider nest (or debris) in the volute coming into the gas and air mix venturi.
  • Power & Flame light flashing

    indicates that the system has attempted three trys for ignition or sensed a flame when it should not be there.

    Things to do:

    1. Make sure the wiring harness to the valve is fitting tight and not loose also the harness at the control module.

    2. Check and/or replace the igniter.

    3. If that does not work and you are getting 24 volts to the gas valve and it is not opening then replace the valve.

    4. If all this fails to eliminate the lights flashing then call the Weil-McLain rep.
This discussion has been closed.