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Trane 55AL Trap

Ran across a Trane 55AL F&T Trap on campus the other day and have a couple of questions...

1:) Is this trap OK to be mounted on it's back? I couldn't find any definitive paperwork on this model and it didn't have the always helpful, glaring "up" or "down" markings on the trap.

2:) What is the consequence of it being installed incorrectly for at least 40 years?...

We still have a few rebuild kits left over for this model # of trap, so want to make sure this one is installed correctly...


  • Steamhead
    Steamhead Member Posts: 16,726
    If the removable cover is not on top, it's installed wrong. In any other position it may constantly pass steam.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • Sailah
    Sailah Member Posts: 826
    My thumb is pointed in the correct direction

    photo 20160216_091428_zps5v1d2ubu.jpg

    Internals shown. Float works laying down like this by pulling up on the seat.

    photo 20160216_091401_zpsd7dknfya.jpg
    Peter Owens
  • SDSteam
    SDSteam Member Posts: 13

    That's how it's installed. I questioned it because I recently found a different brand/model trap in a crawlspace that was incorrectly installed with the cover up like that and passing steam.

    Cleaned out and replaced the internals on this 55 and that took care of some of the issues in this building.
  • iOne
    iOne Member Posts: 4
    Unless the cover on the Trane 55 series is up, the float won't work. Here's an internal photo of a spare I have:

    The Tunstall cartridges work on this unit, to replace the brass bellows.