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Air purge after filter service

Damon Member Posts: 32
I have a Beckett AF running a Thermopride furnace. It's fed by a two pipe system that runs overhead into the top of the 275 gal tank about 5 ft away in the basement. I changed the filter, strainer, nozzle and vacummed out the HX but did not get it to fire afterwards. I pushed the reset about a dozen times (the motor ran about 45 sec per push) and never got a drop of oil to go through the nozzle but I could hear the return line bubbling inside the tank (3/4 full). How many times do you have to push the reset to purge all the air out?  I called a tech since I had to run and he was able to start it but he has not told me what the problem was. I'm thinking that either the seal on the filter was leaking (which you could never hear over the motor) or it really takes a long time to purge this puppy. Also there isn't a valve on the tank side of the filter so I'm curious as to why the oil didn't siphon out when I removed the filter. Is there a check valve built into the filter housing or is the viscosity of the oil plus the overhead lines enough to keep the oil in the tank? It's your everyday Sid Harvey model 264 filter. Thanks in advance!


  • KevinCorr
    KevinCorr Member Posts: 106
    purge fuel pump

    There is a nozzle on the side of the fuel pump that you can open so when you start the boiler you can purge the air out then shut it when it flows clear. You can use a can or pan to catch the oil.

    I would put a valve on the inlet of the filter. I don't know why there is none or why your tech did not install one.
  • George_11
    George_11 Member Posts: 11
    dangerous and scary !!

    You want to save a few bucks so you service your burner,how hard can it be ?  two pipe system and oil returning back to the tank , but filter not primed? pushed reset twelve times ?t Did the service tech  know you reset it that many times? I would have replaced the primary, 3 strikes and your out.  What did the tech find?
  • EddieG
    EddieG Member Posts: 150

    5ft away from the tank, should be a one pipe oil line set up! For a whole lot of reasons. Your flowing and filtering a lot more oil than you are burning.
  • Damon
    Damon Member Posts: 32
    Saving a few bucks was not part of my justification …

    for working on my furnace. I’m an engineer who likes to tinker so my goal was to properly clean it and have a Tech tune it since with 1-1/2” of soot in the flue, I doubt if anyone ever cleaned the flue or HX like I paid them for every year since it was put in service 13 years ago. Two different companies worked on it so it would just be finger pointing if I complained about it at this point. They changed nozzles and filters and tuned it but I’m convinced that was it. Too bad I couldn’t find a pro from the Wall out in the Hamptons by using the find a professional link.


    Anyway, I haven't been to the house since I started this thread but the guys who have been working on my house since I left said the heat is on and the service tag just has combustion readings on it. I haven't seen a bill from the oil co. yet so I guess if they send one and want to get paid they'll have to pony up some info :). The co. who just serviced it originally installed it and all the duct work plus my AC a few years later so I can give them a little grief.


    After reading some other posts, my bet is that they just primed the filter and/or used a vacuum pump to prime the line. I do remember that there is a notation on a tag from ~1998 stating "needs valve before filter" possibly because it doesn’t self prime once the line drains and yeah they should have put one in there to begin with. Opening the bleed valve on the pump did nada for me since not a drop came out. I even pulled the line to the nozzle and got nothing there either so I just called a Tech since he needed to come tune it anyway. Yes the tech knew how many times the reset was pushed and I checked to make sure that there was no oil in the chamber after pushing the reset each time so there was no risk of a puff back.


    There is one positive about a two pipe: one less leak point since the fitting is at the top of the tank. In some cases the increased oil filtration of a two pipe may not be a bad thing either. Other than better head for the pump and getting the sludge out from the lowest point in the tank I’m curious as to why a one pipe is preferred. (Man this post is verbose!)
  • Coany
    Coany Member Posts: 91
    read the control/ find the air leak

    does it have a prime feature?

     where the burner would run for up to 4 minutes while trying to self prime?

     I would look hard for air leaks, especially around the oil filter.

     Double check the filter gaskets and bleeder port, and look hard at the strainer cover gasket as well.


    There was an error rendering this rich post.

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