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Basic Beckett

keithnh Member Posts: 1
Have a double mobile and Miller/Beckett CMF-100 furnace. The 20 yearold original CMF-80 expired 2 years ago and I found a CMF-100 with natural gas burner cheap in very nice shape. Did some reading and used to work on burner management systems as a tech so decided to convert to oil. Trying to get some basic troubleshooting down so I can handle a few things. Also wanted to rig a spare furnace eventually for my garage. Right now Im thinking of what I can do to make operation and troubleshooting as efficient and easy as possible.

1. How to verify adequate fuel delivery
2. How to remove air from single line with below level tank 30 feet away
2. How to know ... precautions to take for not lighting off a loaded firebox

My burner has been running although squeaking ( I think like air in the pump ) reliably all winter so far and did so last year as well. Had rebuilt pump and motor installed on used case-transformer-control setup with all new nozzle electrodes fire tube and end cone (Beckett) ... was adjusted by my oil company tech ... paid him an hour to setup. I now have the squeaking as well another similar to the old setup in that right after a delivery ... especially if tank is a little low the furnace quits. Just had delivery today and am sitting in cold house. Usually I would...

1. dump in Diesel 911
2. remove Garber filter with gauge and clean it
3. hit fittings near filter and copper line with torch to hopefully melt any ice
3. verify steady stream out of oil tank into bucket when filter removed
4. run my torpedo heater in the basement near (aimed at) the oil tank and filter
5. try to bleed any air out of pump feed line

Usually these steps bring it back online ... but am never sure Im getting bleeding right, or is pump going bad, did I get bad fuel, is there a bunch of chunks in the bottom of my tank I cant see ... what exactly did I do that fixed it ??? Wish I could isolate cause better.

Was going to try a Tiger-loop setup that basically emulates a 2 line system but am not sure it would help my situation


  • icesailor
    icesailor Member Posts: 7,265
    If the tank is below the burner, it must be a 2-pipe system. You're better off to convert to a Tigerloop.

    Its hard to DX your problem on the Internet.