Many tank-style water heaters – particularly those powered by electricity and not natural gas – feature two thermostats because they have two
Adjust both thermostats to the same temperature setting. WARNING! Higher temperatures increase the risk of scalding. If you have increased the temperature setting above 120°F, install Thermostatic Mixing Valves at each point of use and set them to 120°F or lower.
Most electric water heaters above 20 gallons have two thermostats that sense the temperature of the water in both the top and bottom of the tank. The upper thermostat is the boss and always tells the lower thermostat what to do.
An electric storage-tank-style water heater has two thermostats because it has two heating elements. The thermostats are designed so only one element is active at a time.
When a significant amount of hot water has been used, the upper thermostat will take priority and heat up the top portion of the heater. Once heated, it will flip/switch power down to the lower thermostat and heat the lower portion.
Many tank-style water heaters – particularly those powered by electricity and not natural gas – feature two thermostats because they have two heating elements. They have a heating element at the bottom of the tank and another heating element at the top of the tank.
Dual-zone HVAC works by using two or more thermostats that are connected to dampers within your home's air ducts. These thermostats are then programmed to open and close the dampers depending on which zone is meant to receive heated or cooled air.
A typical electric water heater has two thermostats: an upper water heater thermostat and a lower thermostat.
120 degrees Fahrenheit is the safety recommendation against scalding, but 140° is the common default setting. Most experts agree that anything below 120 degrees creates a risk for bacteria to develop inside your water heater from stagnant water, such as legionella that causes Legionnaire's disease.
Your second tank water heater may feed into the first one so that there is a continuous flow of hot water through the two systems as they work together. In this case, the second tank usually does the majority of the heating to transfer water through the other tank.
The maximum Department of Energy recommended water heater temperature setting you should never exceed is 140 degrees Fahrenheit. The lowest recommended setting should never be below 120 degrees Fahrenheit.
If you are getting no or not enough hot water, it is probably an issue with the upper thermostat. Slow hot water recovery can be an indication of a faulty lower thermostat. If the water is too hot, it is likely that one or both of the water heater thermostats are set too high.
Each element has its own thermostat, and only one element runs at a time. The top element turns on first to start the warming process. Once the water in the top half of the tank reaches the set temperature, the top element turns off, and the bottom element turns on to heat the rest of the water.
The cold water enters the bottom of the tank and the lower thermostat senses a heat change. The lower heating element will heat the incoming cold water. If you use all the hot water in the tank, the upper thermostat will demand heat and withdraw power from the bottom of the tank.
The EPA recommendation is to always leave your water heater set to 120 degrees. This is both so that the unit loses less energy and also to prevent possible scalding. OSHA, on the other hand, recommends setting your water heater to 140 degrees in order to aid with cleaning and sanitation.
Just before the water heater, the line splits into two separate pathways which make up your home's water intake system. You turn on the hot water tap. Cold (but soon-to-be hot) water passes the shut-off valve, travels through the dip tube, and enters the water heater tank.
Peel back the insulation. Use a flathead screwdriver to adjust the thermostat up or down. If your water heater has two thermostats, adjust both the same amount. The top thermostat should be a few degrees higher than the bottom.
Although some manufacturers set water heater thermostats at 140ºF, most households usually only require them to be set at 120ºF, which also slows mineral buildup and corrosion in your water heater and pipes. Water heated at 140ºF also poses a safety hazard—scalding.
C - 150° F - About 1-1/2 seconds. B - 140° F - Less than 5 seconds. A - 130° F - About 30 seconds. HOT - 120° F - More than 5 minutes. LOW - 80° F - No hazard.
The top heating element heats the top half of the water to the desired temperature and then turns off. Then the lower heating element kicks in to heat the lower half of the water. You can almost think of it as having two water heaters. Each unit represents half of your hot water capacity.
Each heating element has its thermostat; if those don't work, the elements won't either. Hiring a pro to replace a thermostat averages around $150 to $200. The part itself costs up to $20 and is easily replaceable without disturbing other components if you have some DIY experience.
The recommended setting for this control is 60°C/140°F. (Storing hot water at temperatures of less than 55°C is not advisable due to potential for Legionnaires disease). If the water coming out of your taps is too hot then check this control as it could be set too high.
One house can have two thermostats — the two thermostat units connect to one HVAC unit to make your home more comfortable by giving different zones a different temperature as desired. An HVAC professional will also install dampers and controls for better temperature regulation in those areas.
This means the power to the unit can only operate in one direction or electrical current. Because of this the single pole thermostat cannot be turned off, but only turned down. A double pole circuit, however, has two directional currents providing a double pole thermostat the ability to turn off completely.
Two thermostats may be needed in case you want to set a different room temperature in one room while keeping the temperature of the rest of the house at a lower level.