Is this flex line rated for a 200,000 BTU tankless?

And is a drip leg required?
Thanks

Daniel, did you google the make and model installation instructions? I don’t know off hand, but that is what I used to do for info. :smile:

yes, I tried, and it says not to use a flex line unless it is rated for the BTU’s. From what I can find, I don’t think it is rated for that much. But I also didn’t see anything in there about a drip leg.

No. And Yes.

Thanks chuck.
From what I could find, the max rating for that was about 150k, probably less since it was 24"long.
So I did list both of those defects. Could that cause any damage to unit? Or just affect performance with high demand?

3/4" connector is good for 200k BTU, you do need a dirt (not drip) leg

If the connector was 1/2 then it’s not rated for 200k BTU and you may have a pressure problem and it may not burn correctly.

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Uses a type III vent

Restricted gas line, I believe will just result in reduced performance.

Sorry about misinformation on the sediment trap. I was driving to MT and couldn’t check manual. Listed device installation instructions take precedence over IRC

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Thanks, marcel

Pulling up an older thread, but just want to verify.

Navien tankless 240a on LP gas. Flex looks adequate but no sediment trap, plus not sure about the hard 90 degree at the flex connection. I looked at the install manual for this model and although not stated, images show sediment traps. Pretty sure I’ll set it up as further evaluation by a certified manufacture’s installer. Yea/Nay?

It will need a sediment trap. If the tankless water heater has a 1/2” inlet chances are the 1/2” gas flex will be just fine.

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Thanks Martin! First one I’ve seen that didn’t have a trap but wanted to double check. Appreciate it! :wink:

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You have 2 connectors inline, cannot do that. One per appliance. A lot of these are installed by complete hacks. GL.

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I’m pretty sure the curve should not be smaller that a golfball, Tom.

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Thanks @srechkin , @lkage and @mwilles !! I will recommend corrections be made by a manufacture certified installation/plumbing tech.

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Simon has it. The manufacturer’s specs has the connector rated at 200k BTU as long as the length of the connector is shorter than 5’.