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It’s Cold! My Honeywell Thermostat is Not Turning On!

A thermostat is a standard feature in most homes that we rely on to keep the atmosphere comfortable inside the house. If your Honeywell thermostat is not turning on, you have a major problem on your hands.

The rest of your HVAC system won’t know when to run or for how long to keep your home comfortable for you. What can you do about a thermostat that refuses to start?

Identifying the problem is the first step, but it could be caused by any number of potential issues. Take a look at some of these common problems and their DIY solutions.

Dying Batteries

A battery-operated thermostat may have the easiest fix of all the potential problems. Thermostats that have blank screens, unresponsive screens, or flashing screens might be trying to clue you into dead batteries. Simply replace the old and worn out batteries with a fresh set to determine whether this helps.

Loose Wires

Whether your thermostat is new or old, malfunctioning can easily be caused by a loose wire or one that isn’t properly attached. Some homeowners feel comfortable looking at the electric components of their home on their own. If this describes you, turn off the power and remove the thermostat from the wall. This will allow you to check the terminals and the wires for poor connections. You can use the owner’s manual as a reference for where each wire should be located.

Dirty Thermostat

Over time, your thermostat may begin to collect dust and dirt from the rest of your home. This debris can get trapped just behind the cover of your thermostat and cause some major problems. If you have a Honeywell thermostat not turning on the AC or the heat, this could be a quick fix. Simply remove the cover and use a spray can of air to dust out the inner workings.

Unlevel Thermostat

The mercury switch inside your thermostat must be perfectly level in order to read the temperature accurately. If the unit was mounted crooked, it might have more difficulty taking readings of the air around it. It could cause your unit to short cycle, meaning that it turns on and off again rapidly throughout the day. However, it may also cause your Honeywell thermostat not to turn on at all.

While it may be less than ideal, reinstalling your thermostat is definitely doable for most individuals. Make sure that you use a level to get the mounting perfect before finalizing it and attaching it to the sheetrock.

Broken Sensor

Sometimes, these other solutions simply will not be able to fix your current problem. The sensor in your unit may have finally outlived its usefulness. Some people may choose to replace the sensor in their unit, which can certainly be done.

However, most people find that it is more cost-effective to upgrade to a new model altogether. You can discuss your options with your experienced HVAC technician or do a little homework at your local home improvement store.

Other Troubleshooting

Before you conclude that the thermostat is the problem, you should rule out any potential issues with your air conditioner or furnace. Make sure that the power is running to your units or that the gas valves are open.

Turn the thermostat up as high as it will go to try to kickstart your furnace. You also need to ensure that the thermostat is set to the heat position. Testing the thermostat for the summer months will look a little different. Set the temperature lower than usual to turn on the air conditioner. Make sure the thermostat is turned to the cool position, and the fan switch is on auto.

Give each change approximately five to ten minutes to take effect. Your Honeywell thermostat often gives your HVAC unit five minutes to start up to prevent the units from short cycling.

If you still don’t find the solution, you might want to check this link to find out more tips.

Many of the potential problems are relatively simple fixes that you can handle on your own at home. With just a little bit of research and technical know-how, you can address many of these complaints without ever having to contact a professional!

Michael Joseph