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Pipe Dope PLUS Teflon?



  • ChrisJ
    ChrisJ Member Posts: 11,549
    > @EdTheHeaterMan said:
    > Fuel oil lines and teflon tape is a NO NO ! ! ! This is from the Suntec instruction sheet:
    > IMPORTANT INFORMATION Long or oversized inlet lines may require the pump to operate dry during initial bleeding period. In such cases, the priming may be assisted by injecting fuel oil into the pump gearset. Under lift conditions, oil lines and fittings must be air tight. To assure this, “pipe dope” may be applied to both the used and unused inlet and both return fittings. DO NOT USE TEFLON TAPE!! DO NOT USE COMPRESSION FITTINGS!!"

    Thats because they don't want tape getting in the system.

    But we all know when used correctly this will not happen. Same for gas piping.

    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 2,102
    @ChrisJ This was meant for the original poster!
    Edward Young
    Retired HVAC Contractor from So. Jersey Shore.
    Cleaned & services first oil heating system at age 16
  • BinDerSmokDat
    BinDerSmokDat Member Posts: 30
    Ed, thanks for sharing.

    The way I read that, it applies to the inlet and return fittings at the oil pump only.

    I don't need to change the fittings at my pump, and they appear to be doped, so no worries there.

    My original question came from the tank instructions which say to use dope AND teflon on the 1/2" threads of the OSV valve where it screws into the tank.The OSV valve and it's teflon tape is upstream of the filter, so again, don't think that will be a problem.
    Weil-McLain Gold P-WTGO-4 DOM 07/09/96, rated 1.25 GPH
    Beckett AFG Burner DOM 05/23/96, F4 Head
    Delavan 1.0gph 80° B solid nozzle
    10 Micron Westwood spin-on
  • KC_Jones
    KC_Jones Member Posts: 4,649
    My grandfather taught me to fit pipe, cut pipe threads etc. When he learned, there were no "sealants", for most stuff they used a homemade mixture of graphite and oil.
    Quote from him:
    "Never put anything on the first 2 threads as they do the sealing"

    In theory if there isn't anything on the first 2 threads, tape should never be a problem. In practice people suck so we put rules in place for all the ways people can do things wrong, hence the no tape on oil statement.

    I only know what I was taught and it has served me well.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • HomerJSmith
    HomerJSmith Member Posts: 1,289
    edited December 2019
    Well, the Runtal towel bars with the Oventrop nipples has been sealed leak free with the plumber's secret thread sealing product JB WELD after many tries with other sealing products that failed.
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