temperament (sp?) valve

Old 02-08-09, 12:38 PM
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temperament (tempering) valve

We have a 40 gallon water heater, but need a 50 or larger, space (height) is an issue due to venting in the basement. I know they make "short" versions, but some have recommended a temperament (or temper) valve: it somehow increases the amount of hot water you get from your unit by allowing more cold water to the mix.

Anyone familiar with these?

Last edited by manyLowestrips; 02-08-09 at 01:30 PM.
Old 02-08-09, 01:34 PM
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Tempering Valve

manyLowestrips: Tempering valves are used on boilers or similar devices to make the water COLDER you can only put into the heater the amount thats run out.

The only thing you can do is to increase the temperature setting [SAFETY HAZARD!!] that way you get to mix more cold at the fixture.

Your only choice is to get a bigger heater, sorry.
Old 02-08-09, 02:20 PM
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Shacko help me out here. Unless I misunderstood some of the recent posts, I thought they indicated you could use a mixing valve on the output of a water heater. That would allow the heater to be run at 160 and yet deliver a safe 120 degrees. Seems reasonable did I miss something?

Old 02-08-09, 04:27 PM
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No, Bud, you didn't miss anything.

A"tempering" or mixing valve on the outlet of the water heater will allow the water heater to operate at a higher temperature and still limit the temperature of the water available at a faucet to a safe level. It does this by mixing in cold water automatically and in varying amounts to hold the temperature to a safe (usually about 120 degree) level. Because the water heater is now set to produce a higher discharge temperature it effectively can supply more hot water than it could when controlled to a maximum of 120 degrees and piped directly to the faucets.

What Shacko was referring to was the "tankless coil" installed in some heating boilers to provide hot water without having a separate water heater or tank. Because under some circumstances the tankless coil could output water in excess of 160 degrees the tempering valve is a must.

All that stated you must remember that increasing the temperature of a water heater will increase the amount of energy needed for that heater and for any given amount of insulation on the tank the higher the water temperature the higher will be the losses through the insulation to the surrounding air. On the other hand, these losses though the insulation will still be minimal on newer heaters.

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