Indirect with mixing valve?

adambuild

Is there an advantage to installing an indirect with a mixing valve for dhw? Cheaper to run? More efficient? When is it best to use?

Larry (from OSHA)

for me

The advantages have been safety and more available hot water. The tank I have is set to about 140 and the tempered supply is at about 118. This gives me more hot available and less likelyhood of scalding. Also I find a more consistant temp at the faucet on a long draw. Dave Yates and others will tell you that it also keeps the nasty bugs at bay (legionella). So that's my two cents worth as a homeowner.

Larry (from OSHA)

curiousity kills

m

holy 90 degree.(lol)

ALH_4

Tempering Valve

Tempering valves will let you run the water heater hotter. This gives you more water at the faucet, but will also increase the standby loss of the dhw tank. It might be an easy way to increase an inadeqate tank's output.

Solar domestic hot water heaters typically are run hotter to take advantage of the panels as much as possible. Tempering valves should always be used when installing a sdhw system.

An anti-scald tempering valve is always a nice double-check that the water at the tap is never dangerously hot. Many applications require them for safety reasons. I like Caleffi's version.

-Andrew