Expansion Tank on a rinnai water heater

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Expansion Tank on a rinnai water heater
Author: TMIller01 (PA) I have an expansion tank with a bad bladder hooked up to a Rinnai tankless heater. I was ready to invest in a replacement when I read you don't need one in this system. Can I remove the expansion tank and cap it off? Thanks!
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Re: Expansion Tank on a rinnai water heater
Author: bernabeu (SC) the need for an exp. tank depends not on the type of heater but on whether or not the plumbing 'system' is closed ie. ? can the expansion be absorbed by the main in the street or is there a BFP or metercheck ? ============================================== "Measure Twice & Cut Once" - Retired U.A. Local 1 & 638
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Re: Expansion Tank on a rinnai water heater
Author: packy (MA) ah.. but it depends very much on the type of heater. a tankless heater can not run until you turn on a hot water faucet. so the water can not expand when heated because the faucet is open. the heater shuts off when you close the faucet.
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Re: Expansion Tank on a rinnai water heater
Author: bernabeu (SC) well ....................... D'OH ============================================== "Measure Twice & Cut Once" - Retired U.A. Local 1 & 638
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Re: Expansion Tank on a rinnai water heater
Author: hj (AZ) I will bet that Jrealty's plumber would insist on an expansion tank even with a tankless heater.
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Re: Expansion Tank on a rinnai water heater
Author: bsipps (PA) If your tankless has a recirculating line you need an expansion tank
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Re: Expansion Tank on a rinnai water heater
Author: TMIller01 (PA) Thanks for the response. How can I tell if I have a recirculating line?
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