As home inspectors one of our jobs is to inspect the water heater and report any deficiencies.  While not a requirement here at Gumshoe Property Inspection we also use an infrared thermometer to measure the water temperature when run on full hot.  We usually do this at either the kitchen sink or a bathtub faucet.

But then that brings up the question:  How hot should the hot water be?  And that’s not a straightforward answer.  It’s not clear as mud either so let’s take a look at some of the considerations.  And for clarity, the temperatures we will be talking about will be temperatures in the water heater tank itself – not necessarily at the taps/faucets.

For most households the U.S. Dept. of Energy and the Consumer Product Safety Commission recommend setting water heaters for 120*F.  This will help in preventing serious burns or scalding, but is still plenty hot.

However, setting a temperature below 120*F is not recommended because it increases the possibility of bacterial growth in the water heater tank.

If the household has anyone who has a compromised immune system a setting of 140*F can be used.  This is the temperature recommended by the Occupational Health and Safety Administration (OSHA) as at that temperature bacteria such as Legionella will be killed.  But this temperature poses a significant scalding risk.

But if keeping a higher tank temperature is needed for these health reasons, a water tank booster can be added.  This allows the tank to be maintained at 140*F but mixes in cold water so a lower temperature is achieved at the tap.

So at Gumshoe Property Inspection we’ll report the water temperature we measure and won’t make any recommendations unless what we see is abnormally low or high.  For instance, in my own household the water heater is set for 120*F, but is located in the upstairs attic.  By the time it reaches the downstairs kitchen faucet it has cooled a bit and typically measures out at around 117*F.  So not a concern since I know it is hotter when it leaves the tank.

But if we see it at say 102*F we’ll likely recommend turning it up.  If we see 130*F we’ll likely recommend turning it down, unless there is a valid reason for leaving it there.

I hope you found this informative!  We’ll see you on the next blog entry!  Thanks for reading.

#actionableintelligence #informeddecisions #homeinspection