Replacing Sensors on Your HVAC System

Replacing Sensors on Your HVAC System

Heating System Not Working? What Checks Do You Need to Make First?

by Olivia Morris

When you think about air conditioning, more often than not it is to try and get some relief from a sweltering Australian summer. However, the system in your home can also help you out when one of those cold snaps comes along. Sometimes, this part of the equation may be out of balance and you might not be getting any heat at all when you turn on the system. What can you do to try and diagnose this?

Simplify First

Rather than trying to jump in at the deep end, start with the more obvious components and work backwards from there. This may save you a lot of time and alleviate your problem right away. By ruling out some of the simpler components you may also be able to avoid calling in a qualified engineer.


Firstly, have a look at the power supply, as the HVAC system does need a lot of energy in order to work correctly. Typically, the system is connected to the mains in separate sections, with the air conditioning unit that fits inside segregated from the furnace, which typically sits outside. Have a look at the circuit breakers for both systems to see if they may need to be reset.

Next, have a look at the thermostat, which is a relatively simple component but could be the root of the issue. Sometimes, the thermostat will be independent of the main electrical supply and will run from batteries. While you are looking, replace the batteries anyway as they are sure to run out over time.


Turn the thermostat up so that it's several degrees above the normal temperature in the room and turn the system onto its heat setting. If you cannot detect any heat at one of the vents after a short while, switch it back off and go to the furnace. Check to see if the panel door is closed as this needs to be in this position during operation, but also have a look to see if the interior switch is in the on position. If you've had to make a change, press the reset button on the furnace and check again.


Now, have a look at the ventilation system and check to see if the return filter is blocked. Over time, dust and debris will build up and you may have to clean the filter if it's a permanent one, or swap it out if it's not. Put the filter back in with the arrow pointing in the correct direction.

Your Next Move

If any of these checks fixed your problem, you should be good to go. If not, it's time to call in an expert technician to see what is going wrong.


About Me

Replacing Sensors on Your HVAC System

Welcome to my blog which covers a wide range of HVAC topics. I'm Josh and I live in Perth, Australia. I never really used to think about the HVAC system in my home. I believed that when it was hot the HVAC system would cool me down and when it was cold it would warm my house up. However, all that changed one day when the HVAC system went crazy. It began to blow hot air into my house on the warmest day of the year. The contractor I called out said that one of the sensors had broken. He explained how I could better maintain my HVAC system so I decided to start this blog.