This month I would like to answer a common question we receive here at Kaplan-Kaplan Professional Schools: Often we are asked “what does it mean when I encounter a gas water heater with the thermostat dial turned all the way up?”

Several things come to mind regarding this condition. First, the thermostat simply could be defective and in order to obtain typical heated water temperature the occupants have moved the dial to a desirable temperature. I would recommend this condition be checked by a qualified, licensed plumbing contractor.

Second, and more common, the heater is old and at the end of its useful life. Over time water heaters will accumulate mineral deposits inside. We have seen heaters with over 4-inches of debris at the bottom. This debris acts as an insulator preventing some of the heat from the flame below the tank from being transferred to the water. Oftentimes this condition is accompanied by loud popping or surging sounds from the heater when the flame is burning. Occupants frustrated with the slowness of heated water recovery and/or temperature will push the thermostat to the highest position.

Lastly, someone may have increased the temperature to a level that is too hot. If you are in a house with normal inside room temperature and see steam rising when operating hot water faucets chances are the hot water temperature is above the recommended 120 degrees F. Some inspectors even measure the heated water temperature and report the reading (this is beyond nationally recognized standards of practice). In this case I would recommend to the client that the water heater be set to a maximum of 120 degrees to prevent the scald hazard.

We'll talk next month,

Mike Casey
Kaplan Professional Schools
Now You're Ready For Business!™