"Roy" wrote in message
...
On Feb 13, 9:01 am, Bob wrote:
Hello,

What is the "typical," Safe, temp. setting for the vertical style gas
fired house hot water heater ?

Wife is always complaining about not enough hot water, but am a bit
concerned about making the dialed temp., too hot, and perhaps increasing
the pressure in the tank too much, or making unsafe in some other way.

Opinions ?

Thanks,
B.

Hello,

You have to balance two competing objectives - hot enough in the tank to
prevent the bacteria causing Legionaries' Disease from growing but cool
enough at the tap to keep from scalding (antiscald valves not considered).
To do this, check the water temperature at the hot water tap furthest from
the tank. By furthest, I mean where the hot water must take the longest
path to get to the tap. This tap is likely to have the coolest hot water as
the water had the most chance to loose heat during its travel. Use a
drinking glass with a thermometer in it and let the water overflow the glass
until it is fully hot. You want 120 deg F which is the maximum temperature
various agencies have recommended to prevent scalding. Adjust the hot water
heater as necessary
Now, check the temperature setting of the hot water in the tank. If it
is above 130 deg F, you will have to live with it unless you want to install
point of use heating. If it is below 130 deg F, you will have to increase
it to that temperature as various agencies agree that 130 deg F is the
minimum temperature needed to prevent the bacteria causing Legionaries'
Disease from growing.

Good Luck