Before calling a Houston HVAC repair company, there's a few simple things you should check before giving the AC guy a ring that may be causing your problem that every homeowner should be aware of and may just save you the expense of hiring an AC company! These are super simple fixes that we're confident everyone can do themselves and don't involve any tools or prior knowledge of anything HVAC related and are not dangerous to perform what-so-ever!
1) Check The Thermostat
If your air conditioner or heater isn't coming on, the first thing you'll want to check out is the Thermostat. Many times our technicians go out to our client's homes or offices and it's simply a matter of turning the HVAC system on and switching the system from cool/heat, and tada, the system comes on and checks out fine. So make sure you check that your thermostat is set to cool or heat mode depending on what your trying to accomplish, and also make sure the set point on the thermostat is dropped below the indoor temperature if your trying to cool your home, or set above the indoor temperature if your trying to heat your home.
Usually though, it's not that easy, but don't step away from the thermostat just yet! Many thermostats are also battery powered, so if the screen is blank, you'll definitely want to pop the thermostat off the wall (carefully) and change the batteries. If the thermostat comes back on, then your system is most likely going to turn on very quickly and you'll be back in business in no time. Sometimes however, thermostats have a 5 minute delay from when they recieve power to when they actually start functioning, so if it doesn't immediately respond, try waiting 5-10 minutes for the system to kick on. If you're thermostat or HVAC equipment doesn't come back on after you've waited for 5-10 minutes, don't worry just yet, then there's a few other things you need to check that may be causing the problem and their going to be just as easy to perform as checking the thermostat, we promise.
2) Check the Air Filter
Have you changed your air filters? Air filters can keep both air conditioners and heaters from working properly and we run many service calls and find dirty air filters that are preventing the HVAC system from cooling and even turning on, or worse yet, causing it to freeze in cooling mode or over-heat in heating mode.
Every HVAC system has to pull all the air in your home through your air filter in order to cool or heat that air. So when a filter is clogged because it's dirty, the air simply cannot pass through, and therefore it cannot reach the mechanical components of the system where it can be cooled by or heated. Think of it sort of like a traffic jam, the air just simply cannot pass through the filter to get into the HVAC system to be heated or cooled.
If your air conditioner isn't coming on or isn't operating the way it should and if the filter is dirty enough, you can actually cause damage to some pretty expensive componenets that make up your HVAC system. An extremely dirty air filter will cause an air conditioning system to freeze up and form ice, because without air passing through the equipment, the equipment actually begins to get too cold and freeze! This can cause all sorts of trouble, and even ruin the systems compressor (which is the heart of the air conditioner, and the most expensive component to repair)!
If your heater isn't coming on, or isnt staying on for long, it's another good idea to change the filter. The exact opposite happens with heaters when it comes to dirty air filters, and instead of the equipment getting too cold, the heater actually gets too hot and shuts off. Once again this can cause harm to some pretty expensive components that make up your heater and even cause them to melt!
Most systems can detect if they are frozen or beginning to overheat, so they shut themselves off for safety reasons and also to prevent further damage to the components that make up the system, some systems don't do this though and will allow an air filter to cause some pretty serious damage. So replace the air filter if it's dirty, and if you notice your indoor unit or outdoor unit is frozen, allow the ice to thaw before turning the system back on.
If the system doesn't turn back on, don't fret, there's a few more things you still need to check!
3) Check the Breaker Box
Every air conditioning system and heater uses electricity in some way, which means it has a breaker that is located in your breaker panel, and right now it's something we need to locate and check!
Breakers control and monitor the electrical current that flows through the electrical circuits in your home for safety reasons and almost all HVAC systems have 2 breakers - 1 breaker for the inside furnace (heater) and 1 more breaker for the outside air conditioning unit. Do yourself a favor and open the breaker box and check if you have any tripped breakers. The breakers should be labeled and this is going to tell you what electrical circuit and device/appliance in your house the breaker is serving. Look for a label that says "FURNACE" or "AIR HANDLER" or "AC" or "AIR CONDITIONER" and if one of these HVAC breakers is tripped, try resetting it by switching it first to the OFF position, then turning the breaker back to the ON position.
If your system comes back on and runs without tripping the breaker again, then it was most likely a storm or power surge that tripped the breaker or perhaps even that dirty filter you forgot to change earlier =P. If the breaker immediately trips after you reset it, then you know you definitely have a problem! Don't ever keep resetting a tripped breaker if it immediately trips, this is dangerous! - Either something is broken inside of your air conditioner or heater, or the breaker itself is malfunctioning. You should call the AC guy at this point so he can determine what the problem is and get it fixed.
Remember, some systems don't immediately respond when you turn the power back on to them, so once again give your HVAC system 5-10 minutes to kick back on and keep an eye on that breaker to see if it ever trips again, if your system still doesn't come back on, there is one more thing we need to check before we call a pro.
4) Check The Furnace Light Switch
Did you know your furnace has a light switch? Yep. Furnaces have a light switch that looks exactly like.. well.. a light switch! It's actually an emergency light switch to cut off the power to the furnace just incase it has a problem or someone has to work on the furnace. Most of the time if your furnace is located in your attic, this 'furnace light switch' happens to be located right next to the attic light switch, which makes for a very accident prone situation when anyone is entering or exiting your attic because they often end up flipping it on or off.
We often find that when people are entering or exiting the attic they accidentally flip this furnace light switch ON or OFF thinking it controls the attic light and then accidentally and unknowngly end up turning off the entire furnace, which will prevent both the air conditioner and heater from ever turning on!
So just like the case of a tripped breaker described above, if your furnace has no power, the entire system will not operate, and your thermostat will most likely appear to be blank if it has a screen. Even if your furnace isn't located in an attic space, and happens to be located in a closet, it still has one of these secret light switches and you should still check and see if the light switch is in the on position wherever your furnace is located.
Has anyone been in your attic or near your furnace recently? Perhaps dragging out those halloween decorations? Once you locate this secret switch, if the light switch isn't labled, you may want to label the switch with a marker so anyone who finds in big letters "FURNACE - DO NOT TURN OFF" so anyone who finds it knows not to turn it off and they also know it doesn't control the light located in your attic or furnace's closet. We run many service calls where another home contractor that was working in the attic, such as the cable guy or the plumber, has simply flipped the switch OFF on their way out of the attic, and we run many more during the winter months when people are pulling their christmas decorations out of their attics and accidentally flip this switch off thinking it's a light switch. So check the light switch near your furnace, if it's on, and your system still isn't coming on, it's most likely time to start digging a little deeper into the problem. For that, and checking out other simple issues, check out our free HVAC diagnostics app here on our website, or you can always give us a call to come solve the problem for you!
These 4 simple things can save you the headache of calling out the AC guy and having to pay any type of service or diagnostic fees. We hate to see our customer's overlook these common problems and feel bad when we have to charge our clients a service fee for coming out only to flip a light switch or replace thermostat batteries because they simply were unaware of how their system works. So check these things out before calling any AC company, it may just end up saving you the expense of getting a HVAC contractor out, and you can always call us if you're having any type of issue after checking these things. There may be a few more things to check depending on how comfortable you are with getting your hands dirty and we also have a few more listed under our AC Repair section of our website. We can solve just about any problem over the phone depending on how deep you want to dive into your AC system, and if anything is malfunctioning, we can definitely let you know what it's going to take to get it fixed!
Thanks for reading! Let us know if you need any help!