Water Heater Thermostat settings ?

[Red Green]

Robert Neville wrote in news: [e-mail]:

Gale winds are common.

[Tony Hwang]

Hi, A few times installing new tank or thermostat. I noticed most of them came with temp. set at 140. I have a few tanks at my stores and cabin. They are all set at 135 or 140.

[Ashton Crusher]

I used to keep my water pretty hot, at least 140 because of the dishwasher recommendations, sometimes more. My water heaters had a tendency to fill with gunk and then the bottom element would burn out. I bought a dishwasher with a water heat feature and turn the water heater down to about 120 and most of the gunk problem went away. So my recommendation for your new heater is set it as low as you can get away with considering legionnaires and dishwasher issues.

[krw]

How much of that water sits there breeding bacteria? If the water is kept below (or above) the range where Legionella multiplies, it'll be safe. If it doesn't sit, it'll be safe. I suspect chlorine (city water) helps too, as does (colder) well water.

[Twayne]

Either I mis-spoke or you mis-read: I set the TEMP to 130 period; I did not mean to say one element was set different than the other; sorry if I gave that impression. In this case they were both set to the same temp; 130 degrees. Still too hot for my liking, but hot enough for the dishwasher and I've changed shower faucets to the temperature-control kinds. But electricity got too expensive and we switched to an oil fired water heater and saved a bundle on electricity. Up to now, anyway; not so sure it's a savings anymore with prices so high but it recovers very quickly.

HTH,

Twayne

[Tzortzakakis Dimitrios]

In Greece, especially Iraklion, Crete, we have (mostly) electric water heaters with always one element. We have solar water heaters (not in rental houses), so we have plenty of hot water 330 days a year, free (if you count out the ~1000 euros initial expense for the solar heater) These solars come with a 4kW (auxilliary) element, that has a 1 1/2" thread (IIRC) and either a 35 or 38 mm nut. I always set the thermostat at 60 degrees celsius, which is a good compromise for having enough hot weater and electricity waste. They also have a connecting option to the furnace, so you have 3 ways to heat water (solar, furnace, electric). The classic electric boilers have also one element, usually 4 or 3 or sometimes 2 kW, and I always set the thermostat at 60 C. I also change any bad elements myself ( it goes without saying that you must drain the heater of water before removing the bad element).

[Cwatters]

There is a lot of miss info in this thread about legionella.

It's mainly a problem for water that is _stored_ at below 60C.

So you can use a wax cart mixer to mix hot water fom the tank at say 65C with cold water to produce a safe 44C.

I don't know that specific water heater you have but the sealed type that use a heat exchanger can be run at less than 60C because they can be dosed with chemicals.