Plumbing Questions? Ask a Plumbing Expert.
A thermocouple is a device that records the difference in temperature between two points by turning heat into an electrical current. There are several kinds of thermocouples available. One of the most common types is a K thermocouple which is inexpensive to buy and capable of measuring a wide range of temperatures. Type E Thermocouples are another kind which are non-magnetic and possess a higher level of sensitivity.
Listed below are a few questions answered by Experts on issues related to thermocouples.
To begin with, you should ensure that the pilot has a good flame. If the flame is weak, this could indicate that you have a clogged pilot tube or orifice. If this is the case, take out the burner assembly as well as the pilot tube and clean it with air. A water heater case will also have vents at the bottom to get combustion air. Clear these with compressed air. Also, ensure that the flue is clear and the pipe doesn’t have a bird’s nest. If the problem doesn’t go away even after checking all of the things mentioned above, it is possible that you may have a defective gas valve. If the warranty for your water heater hasn’t lapsed, call the number given on it and ask for a replacement.
When you examine your Whirlpool heater, you will find a fresh air inlet on the left side of the burner assembly at the bottom. When you replace the thermocoupling by opening up the burner, ensure that the screen is cleaned well. It is perhaps better to first use a vacuum and then compressed air to clean it properly. If the screen is dirty, it may not allow the heater to stay lit for a long time. Also, if the heater has a black outer screen around the bottom, make sure it is cleaned as well. The thermocouple also needs to be placed directly in the pilot tube’s flame. If the heater still has a problem after you do all of this, you might have to change the control valve. Whirlpool might ship a part for free depending on how old your heater is. Finally, check to see if the gasket around the burner assembly is intact to seal the burner housing. It could have been damaged when you were trying to replace the thermocouple.
It’s very difficult to find a faulty thermocouple. It’s possible that you could have a gas control valve that is faulty or air take vents that are clogged, in case this is a newer heater with a sealed combustion chamber. If your heater is older, it might not be worth changing the $200 gas valve and you might need to replace the heater. If this is a newer heater, try cleaning the vents to see if it fixes the problem.
Visit the website below for step by step instructions on how to change a thermocouple. It should help you in trying to get your heater working again. http://www.associatedcontent.com/article/584031/how_to_change_a_thermocouple_on_your.html?cat=6
There are a few problems that you can face with Thermocouples based on their composition and the way you use them. Sometimes, the metals that are used in designing a thermocouple are badly welded and solded resulting in poor performance. Another problem you could face with a thermocouple is thermal shunting. As they age, thermocouples can also corrode and become prone to strain and stress. If you have a problem with your thermocouple, consult an Expert to help you tackle the problem.