High Output Indirect Water Heaters

High output indirect water hearers are built with the same basic construction as the residential indirect water heaters with the exception that they are built with much larger heat exchanger coils inside the tank. In modern hydronic systems that are incorporating high efficiency condensing boilers as the main heat source, the investment made in the high efficiency boiler that has been installed to do space heating can be set up to do domestic water heating as well. Hot water from any hydronic heating boiler is circulated through the coil inside the tank to heat all the water in the tank. The unit can be piped like any other heating zone. Heat-Flo manufactures tanks built with heating coils that can transfer 200,000 to 495,000 BTU / HR. These tanks with coils can be banked together for applications such as apartment buildings, office buildings, food service establishments, and other high domestic water heating demand applications.


High output indirect water heaters provide abundant hot water, low operating cost, and long life.



Abundant hot water



The Models HF-85-XHO and HF-115-XHO can take the full output of a 495,000 BTU boiler providing continuous output of up to 660 gallons per hour of hot water @ 90 degree F rise, and up to 914 gallons per hour of hot water @ 65 degree F rise.

Low operating cost results from:



High thermal efficiency if used with a high efficiency modulating condensing boiler

Increased boiler on time increases boiler efficiency

Low standby loss in comparison to center flue gas and oil fired water heaters.

Operating costs of 50% less than an electric water heater are common.

High output indirect coils are also commonly used with lower input modulating condensing boilers. Sizing a high efficiency modulating condensing boiler with an “oversized” indirect heat exchanger coil will result in lower boiler flue temperatures, lower boiler outlet temperatures, and will result in the boiler operating in the condensing mode through more of or through all of the recovery cycle. The result is in the boiler operating with a much higher thermal efficiency.



Long life



High output indirect water heaters do not have a direct flame impinging on tank wall surfaces which reduces lime accumulation. There are no electric elements to burn out. The units are all stainless steel construction. If you are installing or updating a hydronic heating system, or have an existing hydronic heating system, the indirect water heater is an excellent solution. If sized correctly hot water shortfalls and high electric water heating costs are eliminated.



Features and benefits include:

60, 80, 85, and 115 gallon units are available with high output coils for commercial applications.



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