What to do when the thermostat is not working

Finished Controller

A problematic thermostat can be a hassle. (Photo Credits)

A malfunctioning thermostat can be an issue in a household especially during hot summer months, or the dreary cold of the winter. Apart from the inconvenience of having to guess what temperature to set it to get the desired coolness of warmth, it can also increase utility bills. Plumbing Association of San Diego                 

The Spruce tried to explain possible reasons to thermostat troubles, and what can be done about it.

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“If your furnace isn’t functioning properly — and you’ve ruled out the usual suspects: dirty furnace filters, broken hoses, etc. — your thermostat could be to blame. Sometimes, faulty or aging wiring, dust accumulation, extreme temperature changes and other issues can cause your thermostat to malfunction, rendering it unable to properly communicate with your heating equipment and regulate the temperature of your home. Typically, thermostat issues will cause your furnace to stop producing heat, to put out erratic amounts of heat, or to cycle on and off more frequently than is necessary.”

Read the reasons they cited here.

Different thermostats, different issues

A/C And HVAC Compact Appliance for its part explained that there could be different issues in a thermostat that would call for a different solution. One of the thermostats they featured in their article are electro mechanical thermostats.

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“Electromechanical thermostat devices are older and more basic than modern examples, operating on very simple mechanical principles.  A strip of two different metals joined together rests just under the cover, sometimes in the shape of a coil. This strip, or coil, will expand and contract with the fluctuating temperatures, activating the contacts on either one or both sides of the metal. If the unit controls the heating and cooling functions, it will have contacts on both sides; if it only controls one option, it will only have a contact on one side.  In a dual-controlled unit, this switch will tilt one direction if it is hot and the other if it is cold, creating contact with the appropriate side to activate the heater or the cooler to turn on. This system is sometimes joined with a mercury switch, which is a tube filled with mercury that also tilts as the coil expands or contracts, causing the mercury to move from one side to the other and thus opening or closing the points of contact.”

Check out the other types of thermostats here.

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SF Gate meanwhile gave its readers pointers on how to determine if the problem indeed lies on the HVAC’s thermostat.

“Set the thermostat at least 5 degrees higher or lower than your normal setting, depending on the season. Set it 5 degrees higher than normal during heating season, and 5 degrees lower during cooling season. Check that the appropriate device comes on. (2) Determine whether another problem might cause the device not to work properly. Check that the thermostat is correctly set to “Heat” or “Cool.” Check that the main circuit breaker for the furnace or air conditioner is in the “On” position. (3) Turn off the power for the furnace and air conditioning systems by switching the appropriate circuit breaker to the “Off” position.”

Read the succeeding steps here.

Thermostats can malfunction, and routine inspection and checking can help prevent bigger problems in HVAC Use.

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