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Does a tankless water heater require a thermal expansion tank?

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2010-05-21 17:52:00

In America, local building codes will decide. For example, in

Pinellas County, Florida, they are required with every tankless

installation, but not required in some surrounding counties. Always

use a certified plumber, and hold him/her accountable to meet local

Codes via the Inspection process. Contact your local Building

Inspection officials for info on equipment requirements and


Expansion tanks are ALWAYS a good addition to a gas or electric

tankless system. All of these systems have their own controls that

adjust the amount of heat applied to the water in the coils. If

these malfunction, overheating may cause a steam bubble to be

created inside the tankless heating unit. An expansion tank allows

for the extra pressure from this expanded water to be absorbed


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