Question about Hayward H400FDN Low NOx Natural Gas Pool or Spa Heater

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About to purchase and install a Hayward H400FDP Propane 400,000 BTU Univeral Low-Nox Pool Heater. Manual clearly states that a 1" PIPE is required for runs less than 50 feet. Tubing is not listed as an option for this heater although it is for lower BTU heaters. My run is under 30 feet. The Propane company that is installing the propane tanks is telling me that their installation will use 7/8" tubing and that it will be sufficient. Hayward's manual clearly states that they will not be responsible for issues caused by insufficient fuel being delivered to their heaters. Should I let the Propane company install the 7/8" tubing and hope for the best or try to find a new company?

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I would definately go with the manual. I am a warranty station for hayward, and if there is a low gas pressure problem and the meter or line is not sized properly, we will make you remedy that before we can proceed further. Of course that is if there is a gas pressure problem. For me, in this case, bigger is always better. I always suggest 1.25" gas lines. But, i also work in an area where all the supplies are natural gas. Poly Pipe or yellow pipe with a tracer wire is standard material in the area I am in. I do believe when you look at the manual, it will say MINIMUM SIZE. In the end, i would insist at least having the minimum recommended gas line installed. Pool heaters use ALOT of gas. HTH

Posted on Jun 02, 2010


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