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Gas Furnace Troubleshooting Guide - PartsAPS

gas furnace troubleshooting guide

A good gas furnace troubleshooting guide assists you in finding what is going wrong with your furnace depend on its symptoms. That's why we provided clear and straightforward information on the gas furnace troubleshooting guide here. This step-by-step guide will allow you to repair the most common problems that occur in your furnace. With a little experience, you can troubleshoot gas furnace yourself and save a lot of money.

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Gas Furnace Troubleshooting Guide Pdf

If your house is heating with a forced-air heating system, then a furnace is important for comfort in cold weather. So, you should follow the proper maintenance to work as efficiently. However, even with the proper maintenance of the unit, sometimes they can break down and causes problems that affect the regular functioning of the gas furnace. If your furnace is facing any common problems, go through this gas heater troubleshooting guide to fix them.

Furnace won’t Start

If your furnace doesn’t start warming when the thermostat is set to high temperature than the room's current temperature, then mostly causes are the following:

Check for furnace switch turned off, simply turn on it. The furnace might have a short delay while for starting. Also, look at the circuit breaker. If it trips continuously, there is likely seems wiring short in the furnace.

Sometimes, the thermostat is not working because of loose connections.

When thermostat batteries bad or powered, it needs batteries replacement. The issue can be determined by using a multimeter that shows a complete circuit.

Now, go through the filter. Over time, these will get dirty. Dirt and dust quickly caused clog the filter which results in rejection of airflow and poor air quality. Also, prevents the furnace from turn on. So, you have to clean furnace filter regularly. Otherwise, you need to be replaced.

If an issue with the main control board of furnace, better to take the help of an HVAC technician.

Blowing Cool Air

When the furnace not producing heat, you have to check power getting by changing the fan switch from "Auto" to "ON" position. If the fan comes ON, you can consider the unit getting power. The other issues likely the following:

The problem may be caused by gas turned off. So, check for gas supply line near the unit to make sure it is parallel to the gas line.

Inspect gas control valve. If it is not opening, then it has to be replaced. Also, check the igniter and draft motor. If the fresh air intake is blocked by snow or debris, it needs to clean.

Draft Motor Runs but Furnace won't Start

The draft motor is also known as the inducer motor. This motor pulls gas through the furnace and out the exhaust stack. If the draft motor starts and the unit shut down, the reason might be the control board of the motor has failed and have to replace it. Blocked exhaust chimney or blocked air intake are the causes so that must be cleaned. Otherwise, the problem with the gas valve and igniter. If your draft motor not starting, the problem is either the bad motor or with a bad supporting capacitor.

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Flame Starts but Furnace Shuts Down

When you face the problem of the burner starts to make heat but it shut off quickly without warming your house, it may be happened because of the flame sensor's corrosion. So, you have to try it once by removing corrosion on the flame sensor.

Blower Won't Turn Off

If the blower motor runs continuously all the time, then the problem might be with the fan switch, relays in the control board, and thermostat.

The fan switch on the thermostat is positioned to "ON" rather than "Auto".

Relays in the control board may be stuck in the closed position that results in the blower will get constant electric supply. So, you should replace the control board.

The thermostat has contacts that control power to the furnace, they can be worn so that better to make a thermostat replacement to solve the issue.

Furnace Soon Shutting Off

Sometimes there is a problem of furnace shut off when the burner lights. In this situation, you have to check for the furnace filter is dirty and should be cleaned. Otherwise, with the failure of the flame sensor and thermostat, it may occur. So, first, replace these parts, still, the problem persists, consult an HVAC technician. 

Furnace Makes Noises

If you heard a loud noise that may indicate a mechanical problem, clogged burner, or airflow reductions. If you found that the noise is the effect of air running through the ductwork, the solution is to insulate ductwork and reduce noise.

When your unit makes an odd noise, this may cause the pilot light that improperly adjusted or blower motor lubrication ports needs oiling. Also, the problem may be with belts or burner.

Popping or pinging sounds: These may be with thermal expansion.

Rattling sound: It will occur due to the loose panels so that tighten them.

Grinding noise: For this, you have to repair motor bearings.

While gas furnace troubleshooting you should consider manufacturer instructions for security purposes. If you are unable to fix your gas furnace problems, consult a repair person. Moreover, you can get the gas furnace troubleshooting chart in your owner's manual. In case, if you want to get the guide in a file format, get the gas furnace troubleshooting guide pdf on the manufacturer's website.

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Final Words:-

Hope the provided Rheem gas furnace troubleshooting guide will help you a lot and solve common issues. Bookmark our website, i.e., to get more troubleshooting tips for your HVAC equipment. Although, you can buy Heating, Ventilation, and Air Conditioning units replacement parts at PartsAPS. OEM parts will be supplied.

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