Rheem Pool Heater M5350ti-1

Make sure you know what kind of furnace you have before you start making repairs. Most common furnace in Southern Illinois is a forced air, gas furnace. Here are some troubleshooting tips for fixing your broken furnace:

1. Check the furnace filter. Is it clean? If it's dirty the air flow out of your registers may seem low. If it is super dirty it can completely obstruct air flow. Make sure that all registers are open.
2. Check pilots ignition light. (Electronic ignitions do not have a pilot light). If your furnace clicks on or initiates the start cycle, but does not fire up, you likely have a faulty or dirty igniter/sensor. This is one of the most common furnace problems. Under normal conditions, the furnace is notified by the thermostat to click on, the igniter gets red hot and then initiates the entire process of igniting the gas and blowing the hot air. If you feel comfortable enough, check the error codes in your furnace user manual to make sure you do not have a more serious problem. To fix the furnace that won't start, turn off the power to the furnace-and turn off the gas. Remove the front panel and look for the igniter/sensor. Refer to your user manual to locate the igniter. It is usually located near where the flames shoot out of the burners. Basically, the furnace will not continue in the starting sequence because the sensor/igniter is dirty and needs to be cleaned. It is very easy to remove the sensor with a screwdriver. Clean the probe on the sensor by rubbing it with some medium grain sandpaper. Do a thorough job, but be careful not to break anything. Replace the sensor exactly the way you found it. Put the front panel back on, turn on the gas, and then turn on the power. Turn up the temperature on your thermostat to see if your furnace will fire up. If this doesn't solve the problem, time to give a technician a call.
3. Check your thermostat. Make sure the temperature control settings are set to above the current room temp. Also make sure it is on the HEAT or AUTO setting. You can try to get the furnace to turn on my setting the thermostat to as high as it will go.
4. Make sure the furnace is on. There will be a power disconnect switch next to the furnace. Yes, even gas furnaces you electricity. You can also check the fuse/breaker to make sure the furnace breaker has not been tripped.
5. Is the gas supply to the furnace open? Check to make sure the gas control valve to the furnace is open. If it is not open then your furnace could have no fuel. If you smell gas, leave immediately and call a repair company.