mixing valve on a water heater?

Charlie from wmass

Ted it may be for bacteria growth. What State are you in? In some states, not Mass yet, the water heater is to be above 140*F to curb bacteria growth and the water to the faucet is to be 120*F so you use a mixing valve. What type of water heater are we talking about, electric, gas, or indirect?

Ted Keane_2

mixing valve on a water heater?

I looked at a job today,and they had a mixing valve on their water heater.It's a brand new water heater,for domestic hot water only.Does anyone know why you would do this?I'm going to put a water softner on the water heater.Thanks.

bob young

LEGIONAIRE'S DISEASE

you can run tank at higher temp. & temper water to safe level more accurately. or run dedicated hi- temp . line for dishwasher , etc. use a HOLBY . you can't go wrong

Ted Keane_2

It's a gas water heater.I'm in Park City,Utah.The house is at 6500 ft.I've found that if you turn water heaters up too high without a high temp relief valve,they will drip or blow out the standard relief valve.I haven't heard of much bacteria growth in water.Most water is really hard.Thanks,Ted

hot_rod

most, if not all

homes in Park City have water meters with backflow preventers built into the yoke. This was enacted may years ago so the city could qualify for federal grant money to make water distribution up-grades.

The DHW thermal expansion tank needs to be properly sized to the tank(s) capacity.. if it has one, be sure it hasn't water logged. if it doesn't have one, it needs to be installed.

The relief may seep when increasing the temperature as is has more thermal expansion. PC water, in winter can drop into the 30's. taking that to 140, 160 or higher, a large delta T, requires a properly sized expansion tank.

I see more and more WH manufacturers includuing mix valves with the tank. Bradford white has shipped mixers with many model. The CombiCor for example.

For a while that Watts ballcock with built in pressure relief valve was another form of thermal expansion control, but it was dropped as it wasted a lot of potable water down the drain.

The water storage up Deer Valley had a terrible bacteria issue many years ago, very little summertime use, warm summertime conditions, etc. Whatever the bacteria was it was actually eating away the toilet flappers in tanks! I wish I had a digital camera in those days.

hr