You are in Phoenix. We also have a Tucson site.

You are in Phoenix. We also have a Tucson site.

You are in Phoenix. We also have a Tucson site.

Thermostat Troubleshooting Tips  

Picture this: right as the evening temperatures here in Phoenix dip, your thermostat starts making frustrating promises it can't keep. The tantalizing "heat on" notification feels like a warm mirage in the frigid air of your home, especially as you try setting the temperature higher and higher. What gives?

When your thermostat says "heat on" but no heat comes, don't panic! A bit of troubleshooting may help get your home from cold to cozy in no time. Read on for the steps you'll need to take.

Understanding Your Thermostat and Heating System

Your thermostat is the heart of your heating system, so let's start with a few basics.

When you choose your preferred temperature, your thermostat starts measuring your home's current temperature. Next, it switches on the heating if the temperature is below the one you've chosen. If you have a programmable or smart thermostat, it will even do this for you automatically.

Obviously, these devices need power to work. Some thermostats are battery-operated, while others communicate with your furnace, boiler, or heat pump via a wired connection. Whichever type of connection you have, this setup allows the thermostat to tell your system how much heat to deliver and when to deliver it.

Common Causes for the Issue

What happens when something disrupts your thermostat's reading, power, or communications? Well, your thermostat may not deliver heat! Here are a few common culprits behind this issue:

  • Wrong setting selected by user

  • Improper temperature calibration

  • Electrical or digital malfunction

  • Dirty air filter

  • Pilot light issue

  • Ignition problems

  • Insufficient power supply

With a bit of troubleshooting, you can rule out errors and figure out what's causing this mishap.

Basic Troubleshooting Steps

Even if you're wary of messing with your HVAC system, there are a few troubleshooting steps anyone can try:

1. Check the Settings

With the wrong settings, your thermostat may not tell your heater to power on. Make sure the heat is "on" and the fan is set to "auto." Your desired temperature should be higher than the room's current temperature.

Check the Power Supply and Gas Valve

Replacing the battery of your thermostat can sometimes help. In rare cases, a failing battery can cause minor power issues and malfunctions. You should also check that your entire heating system has power. Make sure the power switch is on and check your circuit breaker for issues. If you have a gas furnace, don't forget to make sure the gas supply valve is open!

2. Look for Red Flags

Last, check for any obvious signs of trouble. If you see red flags like error codes, overheating, or flashing warning lights, call for emergency HVAC services right away.

When to Check Your Air Filters

We know, we know: we're constantly reminding you to check your filter. This is because it's great for your system! Just like a clean air filter helps you breathe better, it also helps your system breathe. 

Your thermostat tells your furnace or heat pump to warm your home, but your system may shut down if it can't handle the strain due to a clogged filter. This may lead your thermostat to claim that your heat is "on," even if the system is struggling to keep up.

If it's been over three months since you looked at your filter, change or clean it as needed. Make sure to choose a quality filter for better airflow.

Advanced Troubleshooting

If the tips above haven't helped and you feel comfortable digging into some advanced troubleshooting, here are a few things to inspect:

Check the Furnace Flame

If you have a gas furnace, check the flame. If it has gone out, relight it.

A healthy flame should burn bright blue, so a sickly yellow flame may be a sign that something's wrong. This can happen when the air intake valve is clogged with dirt. If you notice this, clean any debris from the area to see if it helps.

While you're here, check and clean the flame sensor. A dirty sensor won't register the presence of flames, which may make the sensor shut off your gas supply.

Check the Electrical Connections

If you feel comfortable and knowledgeable enough to do so, turn off the power to your system and check its electrical connections. Reconnect any loose wires and take note of fraying or exposed connections. If you notice any issues, bring them up when you call for HVAC service.

Safety Precautions

When you're troubleshooting any electrical issue within your system, make sure the power to your heater is turned off! Live wires are a major hazard, and they're nothing to play around with.

We also recommend wearing protective gloves when cleaning any element of your system.

When to Call a Professional

If your system isn't working even after the troubleshooting steps above, call a professional. You should also call an expert if you're uncomfortable doing any of the steps we've mentioned on your own.

If you suspect that the issue lies with complex system components such as the motor or the thermostat itself, professional service should be your first step. With a wealth of experience in heating and electrical solutions, Parker & Sons can fix the issue fast!

Preventative Maintenance Tips

Once you've solved your thermostat issues, keep future problems at bay with preventative maintenance. Revisiting your thermostat settings often, checking your air filter, and keeping your system clean and in good condition can help you avoid similar issues down the road.

In addition, don't forget about professional inspections! Scheduling a heating tune-up each fall is a good way to keep your heating system running.

Help When the Thermostat Says, "Heat On" But No Heat Comes

No one wants to deal with a cold home when the heater is malfunctioning. Luckily, the troubleshooting tips above can help! Check your system to rule out any common issues.

When all else fails, Parker & Sons is here to help. With quick and efficient assistance for any heating emergency, we'll get your system back up and running in no time. Contact us today to schedule your tune-up or repair.


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