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AC and Heating Tip from AC Express

Diagnosing a Furnace Problem

Diagnosing a Furnace Problem

In some ways we live in a very Do-it-Yourself world these days. With the internet at our fingertips, it’s easier than ever to answer questions and solve problems that in the past we would be helpless to solve without directly contacting and working with an expert. This is doubly true when it comes to matters of home upkeep. Whether you’re building a deck or fixing your washing machine, the internet and all resources contained within make it possible to get through the whole process by yourself regardless of your previous knowledge on the subject.

Because of this reality, many people like to see just how much they can do on their own when something in their house breaks down before calling a professional. This makes sense, because when you own a home you want to feel like you can take care of it yourself and you want to save as much money as possible when it comes to repairs. Unfortunately, when it comes to systems as delicate and nuanced as your heater, relying merely on yourself and the internet is a bad idea in a lot of cases, but not all. That’s why this tip is going to be all about, if not how to fix a broken furnace, at least how to potentially diagnose it. That way you can discover whether problem has a simple and easy fix or one that’s more extensive and would require calling a professional. When can you troubleshoot the issue yourself and when will it require outside help? Read on to find out how to diagnose a problem with your heating in Austin.

Check Out the Thermostat First

Before you even take a look at the furnace itself, you can rule out many problems by taking a quick look at the thermostat. Often times, when it seems like your furnace has broken down and refuses to work, it’s really just a problem with the thing controlling the furnace, the thermostat. The first step in troubleshooting your furnace is to double-check that the thermostat is set correctly. It sounds obvious, but it can be fairly easy for your thermostat settings to get changed accidently. Either by a kid or while dusting or some other little mishap. Of course, if the thermostat itself isn’t turning on, then your issue is probably a dead battery. Switch out the batteries in the thermostat for some fresh ones and see if that does the trick.

So make sure your thermostat is set to “heat” and that the temperature setting is high enough for the furnace to kick on. Wait a few minutes and see if this solves the issue. If not, set your thermostat to 90 so that as you continue to troubleshoot your heater assuredly kicks on when and if the problem is solved. You can also try cleaning the contacts in the thermostat if it is analog and not digital. This just involves removing the main case of the thermostat and lightly dusting the metal contacts.

If none of that changes anything, you still can’t rule out the thermostat completely. If you want to test it further, there’s a fairly simple procedure that doesn’t require more than a screwdriver. Simply go to the furnace, remove the doors and follow these steps.

  1. Locate the circuit board where the thermostat wires connect to the furnace.
  2. Disconnect the wires connected to the "R" and "W" terminals. (the wires SHOULD be red and white too but aren't always,) Push them safely to the side.
  3. Connect your small piece of "jumper wire" between the "R" and "W" terminals.
  4. Put the door back on and see if the furnace works.
  5. If this works, it was a problem with the thermostat and it will need to be replaced. If it doesn’t, then you’ll have to move on in your diagnosing process.

Air Filter Issue

The next step is the air filter, and that’s because it is just as easy to check on as the thermostat and in some cases even easier to fix. The air filter of the furnace is what cleans the air that circulates through the ducts and in your home and keeps the furnace and your air from building up with contaminants. These contaminants, things like pollen and mold spores, can be extremely damaging to your heater if they aren’t controlled. But the air filter isn’t designed to work indefinitely. In fact, it needs to be changed every few months as it will gradually get worse and worse at its job as it collects more dust and matter.

But as easy as it is to replace an air filter, sometimes it just slips the mind since you don’t have to think about it most of the year. Filter-related failures are probably one of the most common furnace problems out there, primarily because homeowners forget about the filters. How do you know if this is your furnace’s problem? First, check your filter for obvious dirt. Don’t try to skimp by cleaning and reusing cheap hardware-store filters. Once they’re saturated with dirt they won’t be able to effectively clean the air anymore. And luckily, filters aren’t expensive or hard to find. Make sure you get the correct size when you go to the store. Most experts recommend changing your furnace’s air filter once a month to ensure maximum efficiency.

Power Problems

If your heater isn’t producing any heat despite a working thermostat and a clean filter, there might be a problem with a lack of power going to your furnace. First, make sure a breaker didn’t accidently get tripped. Go the electrical service panel which is usually located in the basement or garage or in the room with your furnace and hot water heater. Check for a tripped breaker and reset any that are out of place.

Then, you’ll want to check the service switch for the furnace and make sure it is on. Most units have this mounted to the furnace or ceiling just above. If that’s all good, you may want to check to see if the furnace blew a fuse, which could result in a complete reduction of power to the furnace. Most modern furnaces have 3 amp fuses on the circuit board. Though it might be located differently on the board on different furnaces, it looks just like a standard size fuse you might find in your car and should be easy to find if it's there. If you have an indicator light and it's not on or flashing, this may be your problem and is easy to determine and fix.

Simply pull the fuse off the board and visually look to see if the link inside is burned or if it is broken. If so, you should be able to pick one up at the local hardware or automotive store and replace it. Don’t substitute the fuse with one of another amp rating.

Status Code Light

As mentioned in the previous section, some furnaces have an indicator light or a status code light that can act as a sort of troubleshooting guide all of its own. If your furnace’s control system has a status code light, check to see if there is a service label that indicates what the light is trying to tell you. Some controls use short and long flashes that indicate what or where the trouble is. These lights usually will repeat the sequence until the fault is corrected. Take the time to verify the correct sequence so you don’t confuse two short and one long flash with one short and two long flashes.

If the light is on and steady then the problem isn’t being communicated by the indicator light. If the light is off completely then the problem is probably with the power and you’ll have to contact a professional if the previous troubleshooting tips didn’t work. But if the light is flashing and blinking then you can use to help you diagnose the problem.

This light is going to work a lot like Morse Code. Except in this case it won’t be giving you the letters of words. Instead, it tells you a number that is a code for a specific type of problem that you can look up. If it's a single digit, it will repeat the same dot pattern over and over with short pauses in between, like dot, dot, dot, pause, dot, dot, dot, pause. This would be a "3." If it's a double digit number, it will use a dot, pause, dash, pause pattern to guide you on your way, like this: dot, dot, dot, pause, dash, dash, dash, pause, dot and so on. This would be a "33." Then it’s just a matter of matching the code to the indicator chart which can usually be found on the door to the furnace.

Knowing When to Call a Professional

Perhaps the most important piece of information to take from this tip is that there are many instances when repairing or attempting to repair your furnace yourself is not worth the risk. While you may save money if you’re successful, you could lose significantly more if the problem worsens. The hard thing about diagnosing and repairing your heater yourself is that there are just so many factors and so many things that can trip up a furnace it is nearly impossible to eliminate all possibilities yourself.

So by all means, take some of the information outlined above and use it to your advantage to rule out some of the more straightforward and easily solved problems that can plague your furnace. But if nothing above seems to solve or diagnose the problem, don’t hesitate to call a professional Austin heater repair service. Never perform work on a furnace if you're not sure of what you're getting into and that you've taken all the safety precautions that you can with gas, electric and sharp edges. A career in HVAC requires knowledge of all these things.

Heater Diagnosing and Heating Repair in Austin

Hopefully now you feel more confident in your ability to take your home repairs into your own hands and troubleshoot some of the many problems that can cause your heater to not work as it should. From thermostat issues to power problems, many things that can go wrong between the beginning flow of electricity and the warm air delivery in your heating system can be solved with a few basic tasks and steps.

For the problems that can’t be solved so easily, there are always experienced companies like AC Express who can perform heater repair in Austin with ease. If your Austin heating isn’t working like it should and you don’t know why, call AC Express for quality repair in the area, from Buda and Kyle to Lago Vista and Taylor. Call today!


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