Hot water temp.

tested at 140 degrees, what would be normal range.


Most mfg recommend between 120° to 125°. Some inspectors like to see higher to combat bacteria, i.e. Legionnaires, etc. I stick with 120°

120 unless a tempering valve is installed on the outlet of the water heater.

Scalding potential if higher than 120.

How did you test it? IR them, mercury, probe?
How long did it take to get to 140?
Where at kitch, tub, all fixtures?
Just curious.

We write up all water temp any over 120 F needs immediate adjustment.
Below is a chart that tells how fast you can get burnt. ( F )
… Cookie


52 (125) 2 min

*Usual temperature of home water heaters.

55 (131) 20–30 s
60* (140) 5–6 s
66 (151) 2 s
70 (151)

°C (°F) Exposure time
1 s
44 (111) 6 h
49 (120) 9 min
51 (124) 2–6 min

**Table 1: Exposure time at given temperatures that

causes deep second-degree burn injury in adults

Thanks everybody for the info…

Temperature Time to Produce 2nd & 3rd Settings Degree Burns on Adult Skin

160°F (71°C)
About 1/2 second

150°F (66°C)
About 1-1/2 seconds

140°F (60°C)
Less than 5 seconds

130°F (54°C)
About 30 seconds

120°F (49°C)
More than 5 minutes

80°F (27°C)

I use 125, as stickers on some brands of water heaters use this temperature.

Tough to say, turn it down to 120 when the manufacturer says 125. :wink: