American Standard Furnace – Troubleshooting Guide

American Standard offers furnaces in three tiers – Silver, Gold, and Platinum. No matter what kind of unit you decide to go for, you might find yourself, at one point, searching for ‘American Standard furnace troubleshooting’.

When your furnace is not heating, power source issues, a faulty thermostat, a dirty filter, and outside blockages might be to blame. The furnace can also start to blow cold air; in such a case, check the blower motor, the fan settings, the drain line, and the filters.

You can dive into the issue a bit deeper before calling a professional. The chances are high that you’ll be able to take care of the problem yourself.  

Top Reasons Why Your American Standard Furnace Isn’t Heating

A Power Source Issue

What it is: even though American Standard furnaces run mainly on gas or oil, they still need electricity in order to function

The unit is able to produce heat inside the combustion chamber, but without the blower fan motor (that requires electricity) the heat won’t go anywhere.

Moreover, a lot of modern furnaces come with an electronic ignition system, so the burners simply won’t light, in case there is a power outage.

How it fails: power supply problems can be caused by a variety of different sources. For example, weather conditions, distribution network faults, and so on.

How to fix: check the circuit breakers that power the unit. If they are tripped, fix the issue.

Also, make sure that the power switch is in the ‘on’ position. If you have just turned it on, don’t forget to wait for at least a few minutes as the furnace can start working with a slight delay. 

An Issue with the Thermostat

What it is: the thermostat is the main control point of your heating system. This temperature-sensitive switch, basically, determines how much heat is going to be delivered by your furnace and when. 

How it fails: the most common reason for a faulty thermostat is dead batteries. Sometimes, there might also be an issue with the wires – they are either not firmly connected, or they have degraded over time. 

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How to fix: you might simply have to change the batteries, especially, if you haven’t done that in quite a while.

Also, do make sure that the thermostat is set right. Once you have verified that the device is set to ‘heating’, increase the temperature, and see if anything happens.

Tip: in order for the thermostat to work, the room temperature has to be lower than the device’s set temperature.

Related: Honeywell Thermostat Not Reaching Set Temperature?

A Clogged Filter

What it is: a lot of homeowners think that the air filter filters out the air in their house and, consequently, increases its quality.

In a way, that is right. But the main job of your furnace’s air filter is to protect the blower fan from dust, hair, and debris.

Fact: your filter has a MERV rating. The higher the rating – the more particles the filter will be able to remove from the air. 

How it fails: naturally, the filter will get dirty or even clogged over time. As a result, it will start blocking the airflow.

A clogged filter will make the system work even harder causing it to wear out faster than it is supposed to. This also leads to higher energy bills.

How to fix: simply change your filter regularly. The exact schedule would depend on the thickness of the filter that you use, whether or not you have pets, and on the overall cleanliness of your house.

Usually, you would have to change the filter once every 1-3 months, if you tend to use the furnace on a regular basis.

Tip: do make sure that you have installed the filter correctly. If you have put the thing in the other way round, it will fail to work. 

Related: Cheap Vs. Expensive Furnace Filters


What it is: usually, a house has supply ducts through which the heated air gets into the rooms. The system also has exterior furnace vents – this is from where the combustion gases escape the system.

How it fails: all the openings mentioned above need enough space around them, in order to function properly. At times, they can get blocked.

For example, homeowners might find snow and nests inside or close to their furnace vents.

By the way, the actual furnace also needs to have enough space around it. 

If there is a blockage, the unit might get too hot. Moreover, it becomes more challenging for a technician to get close to the furnace, if there isn’t enough free space around the unit.

How to fix: proper venting is crucial for your safety. Without it, the system won’t be able to work the way it’s supposed to.

Always check the exterior vents and the supply ducts to make sure that they are not blocked.

Tip: in general, experts recommend leaving 30 inches around the furnace on all sides to ensure proper functioning.

Reasons Why Your American Standard Furnace Is Blowing Cold Air

Blower Motor

What it is: the blower motor is the part of your furnace that pushes the heated air through the vents in your house. 

If the thing is not working, then your home is going to stay cold as the heated air gets lost in the system.

How it fails: the blower motor or its parts can simply wear out over time. Excessive moisture, overheating, and dust buildup might also be to blame. 

How to fix: check if the power is reaching the motor with the help of a multimeter

In case the motor is running, but the air is not moving – check the connecting belt (fan belt). You might need to replace the belt, instead of getting a whole new blower motor. 

Related: Why Furnace Is Not Blowing Hot Air?

The Fan Is Set to ‘On’

What it is: if your fan is blowing hot air only some times and cold air – the rest of the time, then this might be because you have your fan set to ‘on’.

How it fails: this is not a failure, it’s just a special mode that your furnace has.

The fan controls the blower and if the thing is set to ‘on’, the fan will be making the blower work 24/7. And your furnace is not heating the air all the time, right?

This means that, at some point, the blower will be pushing unheated air into the rooms. 

How to fix: simply set the fan to ‘auto’. This will make the fan work only once the furnace is on.

The Furnace Is Tripping the Limit Switch

What it is: the limit switch is a component that, basically, safeguards the whole system.

It tells the blower fan when to turn on and it detects the supply air temperature. 

How it fails: if the component ‘thinks’ that the temperature of the supply air is too hot, it will trip.

This is done to ensure that the whole system does not overheat. The limit switch will make the unit shut down until it cools. 

How to fix: surprisingly, the problem might be with your air filters. 

Clogged filters block airflow over the heat exchanger. This means that this component is going to overheat which, in its turn, causes the limit switch to trip.

Related: Why Is My Furnace Beeping?

Drain Line Blockage

What it is: this might be your cause, if you happen to have a high-efficiency American Standard furnace

These units create water that is then pushed out of the system through a drain line.

How it fails: the drain line might get blocked. In such a case, the water is going to return into the furnace and this will cause the overflow kill switch to shut the furnace down.

How to fix: if you have a broken condensate pump, then leave the job to a professional.

However, dust, mold, dirt, and ice can also cause such a problem. 

If there is an issue with ice, then you would have to wrap the drain line with heat tape. Otherwise, try unclogging the condensate line. 

How to Relight the Pilot Light ?

If you’re a lucky owner of an American Standard furnace with a standing pilot, then you might have to reignite the light at one point. 

  • Follow the small copper tubes that are attached to the control valve to locate the pilot light.
  • Turn off the gas control.
  • Turn the knob to the ‘pilot’ position.
  • Ignite the flame with a spark igniter (if there is one) or a simple lighter.
  • Hold the control knob for 10-20 seconds.
  • Turn the knob to the ‘on’ position.