Gas and Oil Home Heating Furnaces - Furnace switches on/off repeatedly
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Poot
11-08-04, 06:13 PM
Our furnace is a Tempstar and is about 2 years old. This problem may be with the thermostat and not the furnace though. We can home today and the furnace was going on and off rrepeatedly. You hear the furnace come on (fans?) sometimes the polot lights and sometimes not, then the unit shuts down and the cycle starts again within 30 - 90 seconds. I removed the thermostat, waited 5 minuets and placed it back on the wall and the unit came on with no problem. The happened to us earlier this year with our AC. :confused: Oh, our thermostat is a White-Rogers. If I have to replace the thermostat, what is the best kind to buy? I have a digital one now.
Jay11J
11-08-04, 10:03 PM
If yours has batteries, it may need to be replaced? If you have no battery in your t stat, then remove the stat, and put R and W wire together and see if the system holds in. If it does not hold in, then something wrong with the furnace.
Otherwise, I suggest the Honeywell lines.
Otherwise, I suggest the Honeywell lines.
Sharp Advice
11-09-04, 06:00 AM
Hello Poot. Welcome to the Heating Furnaces forum topic and the Do It Yourself Web Site.
The most common cause for the cycling, as you described it happening, is the flame senser. Usually just dirty. Cleaning the sensor usually solves the problem. The flame sensor is an element device usually located on the burners. The part is a round sensor that has wire leads extending from it.
Flame sensor is an element rod like part that burner flames heat when burners are on. Located in burner area where burner flames can heat it once flames are present. Size of sensor is larger in diameter than a TC. Locations vary but always in the front of burners and usually close to the glow ignitor.
Cleaning the element is a simple matter of using a fine grit piece of sanding paper or steel wool. The part may have to be removed to accomplish this task. The connection points of this device should also be checked to insure a good clean connection.
First turn off all electrical power to the heater and turn the thermostat to the off position or lower the temp to it's lowest possible temp. Remove the sensor, if needed. To clean it, use fine grit sand paper or steel wool. Clean the entire element to remove the rust, scale etc.
If the element has to be removed to perform this task, make note of how it is currently installed and how it is attached to the electronic module, etc prior to removal.
Reinstall it exactly as it currently is. At this time also check the flame sensors electrical connection. Both of these 2 steps, cleaning and checking the connections should or could correct the problem. If not, it's possible the sensor element is defective and needs replacing, providing this part is in fact the cause of the problem.
Retail heating parts dealers, heating agents and part supplers can also help determine what the possible problem may be. Bring the make, model and serial numbers. Dealers are an excellent source for original replacement parts and are listed in the phone book.
Resident do it yourself heating professionals replying within this forum, could have additional helpful information, suggestions, advice. Check back on your question several times for additional replies.
Use the reply button to add additional information or questions. Using this method moves the topic back up to the top of the list of current questions automatically.
Be sure the electrical power to the appliance is turned off, the thermostat is turned down or off before attempting any repairs.
Personal Reminder:
Buckle Up & Drive Safely.
"The Life You Save, May Be Your Own."
The most common cause for the cycling, as you described it happening, is the flame senser. Usually just dirty. Cleaning the sensor usually solves the problem. The flame sensor is an element device usually located on the burners. The part is a round sensor that has wire leads extending from it.
Flame sensor is an element rod like part that burner flames heat when burners are on. Located in burner area where burner flames can heat it once flames are present. Size of sensor is larger in diameter than a TC. Locations vary but always in the front of burners and usually close to the glow ignitor.
Cleaning the element is a simple matter of using a fine grit piece of sanding paper or steel wool. The part may have to be removed to accomplish this task. The connection points of this device should also be checked to insure a good clean connection.
First turn off all electrical power to the heater and turn the thermostat to the off position or lower the temp to it's lowest possible temp. Remove the sensor, if needed. To clean it, use fine grit sand paper or steel wool. Clean the entire element to remove the rust, scale etc.
If the element has to be removed to perform this task, make note of how it is currently installed and how it is attached to the electronic module, etc prior to removal.
Reinstall it exactly as it currently is. At this time also check the flame sensors electrical connection. Both of these 2 steps, cleaning and checking the connections should or could correct the problem. If not, it's possible the sensor element is defective and needs replacing, providing this part is in fact the cause of the problem.
Retail heating parts dealers, heating agents and part supplers can also help determine what the possible problem may be. Bring the make, model and serial numbers. Dealers are an excellent source for original replacement parts and are listed in the phone book.
Resident do it yourself heating professionals replying within this forum, could have additional helpful information, suggestions, advice. Check back on your question several times for additional replies.
Use the reply button to add additional information or questions. Using this method moves the topic back up to the top of the list of current questions automatically.
Be sure the electrical power to the appliance is turned off, the thermostat is turned down or off before attempting any repairs.
Personal Reminder:
Buckle Up & Drive Safely.
"The Life You Save, May Be Your Own."