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What is a condensing heater?

A condensing heater passes hot flue gases through a secondary, stainless steel heat exchanger1 to preheat the inlet water temperature. The exhaust gas is cooled and steam in the exhaust gas condenses on the vent surface. A condensing tankless2 heater is more efficient because of this pre-heating process. Our condensing heater is 93% efficient as compared to 80% efficiency for most non-condensing tankless2 heaters. This saves you about 10-15% more on your water heating bill.

heat exchanger1
A device used to transfer thermal energy between two or more fluids (e.g. air, water, oil). The fluids are typically separated and not allowed to mix.

condensing tankless2
Type of high efficiency tankless water heater that is designed to capture latent heat energy from combustion flue gases. Often 10-12% more efficient than standard efficiency models. Requires special design consideration to deal with the formation and drainage of the acidic condensate (i.e. stainless heat exchanger)

Applicable Models

  • Models: All high efficiency condensing units that utilize PVC, CPVC or PP venting.
Updated on April 17, 2021

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