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Water Temperature Controls

Posted by: Abram Richardson on Wednesday, December 20, 2017

Having tempered and/or hot water in your building may be a mandate by state or local codes but it also adds to the comfort of the building occupants. Tempered water is typically used in nonresidential facilities that serve the public and where no culinary, cleansing, laundry or building maintenance are provided. Hot water is required for plumbing fixtures and equipment used for bathing, washing, culinary purposes, cleansing, laundry or building maintenance. The Florida Building Code defines tempered water as “water having a temperature range between 85° F and 110° F.” and hot water as “water at a temperature greater than or equal to 110° F.”

Water heaters are required for heating and maintaining the water temperature to meet the defined requirements of tempered or hot water. In 2015 the Fifth Edition of the Florida Building Code forbid the use of the water heater’s thermostatic controls as a temperature limiting means thereby requiring the use of mixing valves.

Mixing valves that are used at the hot water source (i.e. water heater or boiler) require an American Society of Safety Engineers (ASSE) 1017 certification. Point of use mixing valves used at a lavatory or sink faucets are required to have an ASSE 1070 certification. Shower valves must limit hot water delivery temperatures and are required to meet ASSE 1016 for individual showers and ASSE 1069 for gang showers.

Gone are the days of simplicity. In its place we now have water heating systems with temperature control which is intended to better protect the end users. 


Example of two ASSE 1017 Certified Mixing valves installed at the hot water
source, standard mixing valve on the right and a high-low unit on the left.
Both mixing valves are piped for hot water recirculation system.