Bosch offers reliable appliances, but what should you do if your gas dryer is not heating? Try these possible solutions first.
Check for Lint Buildup
One of the primary reasons why a Bosch gas dryer stops heating is due to restricted airflow. This could be because the lint screen is clogged or because lint has clogged the vent.
Clean the lint screen every time you use your gas dryer. Clean the vent on an annual basis, both to keep the airflow going and to prevent fires.
Check the vent behind the dryer for blockage. The dryer vent may also be bent or kinked, restricting airflow.
When airflow is reduced, the air heats up in the dryer, and one of the safety mechanisms stops it from heating. By cleaning up the vents and lint filter, you can often open up the airflow again.
Check the Timer Motor
The timer motor operates rotator cams and gears to turn electrical contacts off and on. This operates the timer, allowing it to control the heating circuit.
You can remove the timer motor and check it with a multimeter. If it doesn’t check for continuity, it can be replaced.
The timer motor in a Bosch gas dryer is typically found in the control console. Make sure you disconnect the power before opening the panel.
Troubleshooting Bosch Gas Dryer That is Not Heating
Having a gas dryer is one of the better conveniences we may have in the home. However, when it isn’t working, we want it back up and running as quickly as possible. Where do you start looking when problems happen with your gas dryer?
Check your gas dryer for a reset button. Typically, it will be located on the control panel. If your dryer has no reset button, unplug it for 10 minutes and plug it back in again. Doing so should reset the dryer and get it working.
Many different issues can occur with a gas dryer. It could be the gas itself or an internal part that keeps the machine operating properly.
Anytime you work on an appliance, whether electric or gas, you need to consider your safety. All too often, people are shocked or killed due to careless actions when doing something they believe is simple.
First, always disconnect the power to the gas dryer before you work on it. The best way to do this is to unplug the dryer from the wall socket. Doing so lets you control the power source and ensure it doesn’t get plugged in.
Otherwise, you can turn off any circuit breakers powering the dryer. Ensure you lock the panel so the circuit breaker does not get turned on accidentally while working on the appliance.
The same is also true for the gas source. It should be shut off at the main, so no gas goes into the appliance while you are working on it.
Be sure to consider your personal safety, such as wearing safety glasses and gloves. If you’re doing anything that creates dust, wear a disposable respirator.
Finally, something is built into most gas dryers that will help you immensely when doing work. Some of the diagnostics that occur with gas dryers are visual, and you will need to ensure that the dryer is firing correctly and heating.
For this purpose, most gas dryer manufacturers will install a peephole so you can look inside the appliance. It will be at a different location, depending on the manufacturer.
A small square cover will usually cover the peephole. You can pop the cover off with a screwdriver and then look inside to ensure that things are working as they should.
Consider these eight different reasons why a gas dryer may not heat properly. When you go down through this list, you may find that one or more than one of these options will work well for you.
Top Reasons Why Bosch Gas Dryer Is Not Heating
1. Thermal Fuse Is Faulty
Most appliances use a small internal fuse known as a thermal fuse. It is a safety device that keeps the machine from overheating.
The thermal fuse is at the top of the list of all the issues I’ve seen when working on gas dryers. You should always check the thermal fuse first, and, considering the low cost, it doesn’t hurt to replace it while you have it out.
Basically, the thermal fuse will stop the power flow to the heater when it detects a high temperature. The problem is, the fuse can go bad and if it is not operating correctly, it may short-circuit and detect a higher temperature inappropriately.
The thermal fuse is relatively easy to check, and it is also easy to replace. After shutting off the power, find the thermal fuse and remove it from the gas dryer.
You should then check the thermal fuse with a multimeter. If it shows continuity, then the problem is likely elsewhere. Otherwise, the thermal fuse should be replaced.
Pro Tip: There is a reason why thermal fuses often fail. If the exhaust vent is blocked, typically because of a lint build-up, the dryer will overheat and cause the fuse to short-circuit.
If you find that the thermal fuse needs replacing, ensure the exhaust vent is cleaned. It would be best to clean it annually because dryer exhaust vents are a common reason houses catch on fire.
2. Gas Dryer Solenoid is Faulty
Your gas dryer heats because the gas flows into the burner assembly, where it is lit. Typically, at least two small devices control the flow of gas to the burner. These are solenoids.
Solenoids open and close, affecting the speed at which the gas flows into the burner assembly. When one of the solenoids fails, or if more than one fails, the dryer won’t get enough gas and won’t heat.
By looking through the peephole, you can do an initial check to see if one of the solenoid coils is failing. If there is no fire, then gas is unlikely to get to the assembly.
The solenoids can be removed from the dryer and tested. Ensure that you have the power shut off to the dryer and turn the gas off at the main before doing any internal work on the appliance.
Remove the solenoid and check it with a multimeter. If you aren’t getting continuity from one terminal to another, then it is likely that the solenoid needs replacing.
Solenoids tend to burn out because they overheat. A high current is sent through the solenoid, causing it to open. As the current decreases, the plunger goes shut.
If the plunger doesn’t shut, the current stays at a high level and causes the solenoid to burn out.
3. Cycling Thermostat is Faulty
We already discussed one item that monitors the temperature inside of a gas dryer, the thermal fuse. The cycling thermostat does something similar. You will typically find it on the blower housing.
The cycling thermostat checks the air temperature in the blower housing. If it detects a high temperature, typically about 160°F, it will cause the unit to shut down.
Your dryer may continue to operate, but since the cycling thermostat is not allowing the dryer to heat, it will take a long time for the clothing to dry.
After disconnecting the power and turning off the gas, you can remove the cycling thermostat and check it for continuity with a multimeter. Replace it if necessary.
4. High Limit Thermostat is Faulty
A high-limit thermostat in a gas dryer monitors the temperature and shuts things down if it gets too hot. It does a similar job to the cycling thermostat and thermal fuse, but it does so in a different way.
The heating mechanism is shut off by the high-limit thermostat when problems are detected. On the other hand, a cycling thermostat helps the dryer maintain the correct temperature by cycling the heat off and on.
If the high-limit thermostat is malfunctioning or has short-circuited, the dryer will not heat. It will continue to operate but without the heat.
Typically, the dryer will heat briefly during the cycle, or the drum temperature will be very low if the high-limit thermostat malfunctions. Remove and test it with a multimeter to verify that it is malfunctioning.
Copyright protected content owner: ReadyToDIY.com and was initially posted on February 28, 2023.
Pro Tip: The high-limit thermostat may repeatedly trip if the airflow is blocked. Check the lint screen and vent for any blockage. If the dryer vent is kinked or crushed, replace it.
5. Flame Sensor is Faulty
The flame sensor in your gas dryer is the item that ignites the gas, which, in turn, heats the dryer. For this to happen, the flame sensor must reach the proper temperature.
If the flame sensor is not operating correctly or short-circuited, the gas will not ignite. You can check this visually and with a multimeter.
Locate the peephole, typically found at the dryer’s bottom front corner. The peephole allows you to look inside and see if the flame sensor is operating and if there is a flame.
The flame sensor will glow before it ignites the gas. If you look in the peephole while the dryer is operating and there is no glow or flame, the problem will likely be the flame sensor.
Turn off the power and gas before working on the machine. Remove the flame sensor and test it with a multimeter. If it doesn’t check for continuity, it should be replaced.
6. Igniter is Faulty
The gas igniter works with the flame sensor to ensure the dryer is heating. The flame sensor detects the flame, but the gas igniter ignites the gas.
You check the operation of the gas igniter by looking through the peephole. After removing the cap from the peephole and looking inside, you should see the flame sensor glowing or the gas burning.
Most manufacturers bundle the flame sensor and igniter as a single unit. While the flame sensor shuts down the gas if no fire is detected, the igniter turns on to light the gas when necessary.
Remove the gas igniter if you don’t see a glow or flame when looking through the peephole. Check the entire unit for continuity with a multimeter.
Copyright article owner is ReadyToDiy.com for this article. This post was first published on February 28, 2023.
7. Clogged Vent Causing Air Flow Problems
A big problem with any dryer, whether it is gas or electric, is for the vent to get clogged. If air isn’t flowing freely, it can cause various issues.
One of the biggest concerns with a clogged vent or an airflow problem is for the gas dryer to stop heating. It will heat up quickly, and one of the sensors will shut it down.
Clean the lint screen every time you use the dryer. It would help if you also had the vent tube cleaned annually.
Keeping the airflow going in the dryer is more than an operational consideration. If the air is not flowing correctly, it can also cause heat to build up and start a fire.
8. No Power to the Dryer
Finally, one of the problems that can occur with a gas dryer is a lack of power reaching the appliance. No power to the dryer can happen for many reasons, but it will always stop the dryer from operating.
The first thing to check is the circuit breakers. Open the breaker panel and find the circuit breaker for the dryer. A gas dryer will typically only have a single breaker.
If the circuit breaker is out of line with the other breakers or has a red line on the side, it indicates a tripped breaker. Turn the breaker off entirely and turn it back on.
If the breaker continually trips, then there may be other issues. The breaker may need to be replaced, or you may have other items on the same circuit, draining too much energy.
The next thing to check is the receptacle. Inspect the receptacle visually for any signs of burning or melting. Plug something into the receptacle, such as a light. If the light works, the receptacle is working.
Check the power cord carefully for any signs of damage. It should be replaced if it is cut or sliced or if you notice burnt or melted areas at the plug.
It is also possible to check the dryer by running an extension cord from a different receptacle to power it. Make sure you check it using a receptacle on a different circuit.
ReadyToDIY is the owner of this article. This post was published on February 28, 2023.