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Should I Turn up the Water Heater Temperature?


Although you rely on your water heater throughout the year, probably every day, it does more work for you during the winter. On a chilly morning, a hot shower feels better than ever—and it can also be a wonderful relief to soak in a hot bath at the end of the day.

So what do you do if the water heater isn’t as warm as it should be? The simple answer would seem to be an adjustment to the thermostat for the water heater (which is called an aquastat). The default temperature for most water heaters is 140°F, although homeowners often lower it to 125°F or 120°F to help conserve energy. If you’ve lowered the temperature during the rest of the year and wouldn’t mind having it back up to the default, then it’s fine to put it back to 140°F.

However, if the reason you’re thinking of raising the aquastat is that the water heater’s performance has dropped, you’re putting yourself at risk of scalding hot temperatures!

Don’t go above 140°F!

Whatever you do, don’t raise the aquastat’s temperature higher than the default setting of 140°F. Above this temperature, the water can rise to potentially scalding levels. An aquastat isn’t as precise with temperature control as an HVAC thermostat. Due to a situation called thermal stacking, the water at the top of the water heater’s tank can rise to extremely high levels and enter the plumbing. Putting the aquastat higher than 140°F makes scalding a serious risk.

Losing hot water is a reason to call for repairs

Even if you don’t turn the aquastat above 140°F, please don’t try to compensate for a faltering water heater by raising the temperature setting. You’re not only creating a scalding risk, but you’re also putting a possibly malfunctioning water heater under greater stress. The system needs licensed plumbers to look into it to discover if it either needs to be repaired or replaced.

To arrange for service for your water heater in Gaithersburg, PA, from repairs to a full replacement, contact our heating and plumbing professionals.

Mallick Plumbing & Heating is the Service Contractor of Choice!