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Tiger Loop

what is a tiger loop & what is its function?


  • clammy
    clammy Member Posts: 3,113
    A tiger loop serves 2 purposes one is to deairate the fuel and the others is to allow your oil burner pump to operate as a 2 pipe system but allows you to only filter what the burner burns . Unlike a 2 pipe arrangement which at a min pumps and re circ about 18 Gph while burning say 1 gallons . Why filter oil your not burning The other good side is it also allows your oil pump see less vacuum being it thinks it an 2 pipe but vacuum is applied to your single feed . The other caveat is when using a pre post oil relay w a valve it auto purges the any air out allow zero fuel cavitation and supplies a stead non foaming oil to the pump and when servicing there’s really no bleed to bleed your burner pump it’s automatic w a tiger loop . Any oil burners that I install or service if on a 2 pipe is converted to a single w a tiger loop . The ultimate danger of a 2 pipe is leak in the return line to the tank big promblems. I believe as far as I know and have seen from 30 years ago in Germany all of the oil fired equiprment that I had seen had a tigerloop they where all relloi burners and a few German brands I believe weissentral burners can not remember but all single pipe and all w a tiger loop . Burner running higher pressure 140 to 150 psi have a tendency to have the pump cavitation on a single pipe greatly effecting burner this is why most European oil fires boiler come w a tigerloop in the burner accessary package . I learned this by installing buderus boilers using Beckett nx burners without a tiger loop there where some issues with a loop smooth sailing . The use of a gar spin on filter is also a good idea w a vacuum gauge ps chk the vacuum gauge connection have had issue w tiny vacuum leaks crappy threads .
    On my own work I always include a tigerloop would think of not installing one ,not using one is just being a cheapstake . Peace and good luck clammy
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating
  • Servicewiz_3
    Servicewiz_3 Member Posts: 57
    Thank you very much , for your help!!