Heating & Furnace Repair

Most likely, your furnace is making a clicking noise and not providing heat because your furnace’s spark igniter is trying to ignite your pilot light or burners but is failing to do so.

In other words, there’s an ignition system malfunction that needs to be fixed. Otherwise, your furnace won’t start.

Before we get into more details, we need to say that this is an issue that an HVAC technician needs to handle. (Sorry DIY folks, there’s not much you can do here.)

If you live in the Atlanta area, contact Coolray for furnace service.

Now, if you want to understand the problem further, read on. We’ll explain:

• What an ignition system is
• Common issues with the ignition system that cause the constant clicking noise

What is an ignition system?

Just like how your car’s ignition system starts your car, the furnace’s ignition system starts (“ignites”) the furnace burners, which heat your air. 

If the ignition system does not work properly, then neither will your furnace. 

To put the ignition system in context, here’s your furnace’s order of operation:

1. Your thermostat calls for heat.
2. The induced-draft fan motor energizes, pulling air up into the burner.
3. The draft switch closes to prove the draft fan is working.
4. The ignition system is energized for approximately a minute.
5. The gas valve opens.
6. The furnace burners light.
7. The furnace blower comes on after a delay of a few minutes and starts distributing air throughout your home.

As you can see, if there’s a malfunction at step 4, your furnace won’t open the gas valve, and the burners won’t light.

Now, let’s talk about that clicking noise. The click is the spark caused by a spark igniter, which is used in 2 common ignition systems:

• Intermittent pilot ignition—Uses a spark igniter to light the pilot flame, which then ignites the burners.
• Direct spark ignition (DSI)—Uses a spark igniter to directly ignite the burners.

Each of these ignition systems can have issues that will cause the spark (the “click”) without igniting the burners.

Let’s talk about those ignition system issues, shall we?

Common problems with ignition systems

Thermocouple issues
A thermocouple is a flame sensor that, when it detects a pilot flame, opens gas valves to the furnace burners. However, if the thermocouple is malfunctioning or covered in soot, it won’t sense the pilot flame and shut the gas valve. The spark igniter will spark (click) for about a minute trying to ignite the flame. 

Pilot light/flame issues
The pilot flame may not be hitting the thermocouple properly due to an incorrect mixture of gas and air. Again, if the flame sensor thinks the flame isn't lit, the spark igniter sparks again and again until it gives up. 

Gas valve isn’t energized 
No gas = no ignition. So if the gas valve is shut, the spark igniter has nothing to ignite and just keeps sparking. Some causes of a shut gas valve include:

• Bad ignition board
• Bad connection between the board and the valve
• Bad valve

All of the above are issues a furnace technician needs to fix. 

Signs It’s Truly Time for a Replacement

While new, more energy-efficient furnaces are designed to last for 20 to 30 years, older ones just aren’t the same way. Here are the telltale indications that it’s time to consider replacing your furnace:

• You’re paying for repair services far too often.

• Your heating bill has skyrocketed even when you are not changing the temperature on the thermostats in your home.

• You house makes a lot of noises, and they seem to be coming from the furnace.

• You set the thermostat, but some rooms feel like a wood-fired smoker while other areas feel like a giant deep freeze.

• There is a crack in the heat exchanger.

If you’re experiencing any of these, we’re sorry, it’s time to say goodbye to your old furnace.

On the other hand, if you are not experiencing any of these things and a technician still recommends you need a new system, here are some reasons why that might not be the case.

Reasons to Get a Second Opinion

1. A furnace technician recommends expensive repairs.

If a furnace technician recommends that your furnace needs costly repairs when you haven’t noticed a problem, you have good reason to be suspicious. If your furnace needs legitimate repairs, the technician should show you each problem, explain the repair, and tell you how much it will cost to fix it.

     2. Pushy sales pitches

Anytime you feel pressured to buy something or pay for a service and you’re not sure about what they’re suggesting, you need a second opinion. If you have any doubts about a technician's proposal and the cost of the service, trust your instincts. Your concern may be well founded. If you hear the same thing from a different company, then you’ve done your due diligence and can feel confident about the decision you make.

     3. A technician tells you that there is a crack in the heat exchanger.

If the furnace repair technician tells you that your heat exchanger is cracked, insist that they show it to you. If the technician isn’t willing to show you the crack, you have good reason to be suspicious; however, a crack in the heat exchanger is one of the top indicators that a furnace needs to be replaced. There is too significant a risk that carbon monoxide can seep into your house, and that’s a dangerous situation for you and your family. So, make sure to call for a second opinion right away.

The air could be warm but still feel cool

Heat pumps usually produce air that is 85-92°F. This is plenty warm to heat your home to your desired 72°F.

But, the air coming out of the vents can feel cold for a couple reasons:

1. Gas furnaces produce air that is 130-140°F range. So 85-92°F feels cold to new heat pump owners.
2. Your body temperature is around 98.6°F (everyone’s body temperature is slightly different, but that’s the average). Since heat pumps produce air that’s below that, it can feel cold to you.

How to tell if there’s really a problem

Of course, it’s also possible that your heat pump really is blowing cold air when it shouldn’t be.

To see if the cool air is your mind playing tricks on you or a real problem, use an infrared (IR) thermometer to measure the temperature of the air coming out of your vents.

If you don’t have an IR thermometer, simply watch your thermostat. The temperature in your home should rise gradually until reaching your desired setting. And then your heat pump should shut off.

As long as that’s happening, everything’s hunky-dory.

What to do if your heat pump is blowing cold air

There are a few reasons your heat pump could be blowing cold air. To solve the problem, try these 2 things:

• Turn off the heat at the thermostat and check your air filter. If it’s dirty, change it!
• Make sure the thermostat is set to “AUTO”, not “ON”. When set to “ON” the fan will stay on even when your heat pump isn’t actually heating. This could make it feel like cool air is coming out of your vents.

If you’ve checked these things and are still having issues, you likely need a professional heating repair company to diagnose the problem.