Question about Heating & Cooling
a 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of.(from cars to computers, handyman, and even drones)
click here to download the app (for users in the US for now) and get all the help you need.
Posted on Jan 02, 2017
Make sure all the wire connections are good and tight. Next lift off the cover and look for a little thermal disc mounted up by top of the heat exchanger. Most have a re-set button but not all. If you have this ,by-pass it ,see if that solves the problem, if so it may be defective, or doing its job and you have a venting problem. If you don't have this and have changed the thermocouple (was it a copper tube with a fitting that screwed into the gas valve, or did it have 2 wires, that is a pilot generator, kind of same thing) make sure the probe is set correct, with the pilot flame heating the top 1/3rd of the probe. The only thing left is the gas valve.
Posted on Dec 25, 2007
I am assuming you are talking about a type K ( Chromel, Alumel ) type Thermocouple. A junction of these two alloys ( welded together by capacitance discharge) produces 41 micro volts per degree Celsius. As the flame from a perfect air/gas mix produces a flame around 1900 C (propane), and 2000 C (natural gas) . You can simply multiply.
41uV X 1900 = 779mV For propane
41uV X 2000 = 822mV For natural gas
This should give you a pretty good Idea of what you should be looking for. If you are using a standard volt meter to obtain a reading. Touching the leads of the probe to the leads of the meter in affect creates two more thermocouples unintentionally. This will alter your reading only slightly due to the fact that the temperature will be at relatively negligible at the contact points.
Allowing for this distortion you should expect a reading +/- 50mV either way. I hope you find this information helpful. Please take the time to rate this fixya for me. To compensate me for the 4 years of my life I spent cramming weird stuff like this in my head in college and the 5 minutes I spent typing this out for you for free. LOL If you ever need my help select me as one of your experts and I will help you for free.
Posted on Jul 28, 2008
SOURCE: thermocouple replacement
Maybe you need to approach it differently. Why do you assume you have a bad thermocouple each time? If its because the whole flame goes out and you have to relite it, a lot of things can cause that.
1 ohm out a new thermocouple and record the ohms reading (read tween the center LEAD looking area on the end going into the gas valve and the outer shell (copper colored cover) If its a MV type controls it will have 2 wire ends. With the flame running now check the MV-DC on the same area, as the resistance. Yes you will need 2 hands extra for holding the flame on. It wont stay on without being hooked up. Typically you need 400MV for a thermocouple and 600 is the stahdardf output on a generator with wire leads depending on which you have. If your below these ranges You need to blow out the piulot area with compressed air and retry it. You should get an increase in the milli volts after cleaning because now the flame will hit the pilot or thermocouple or generator as designed and dust was causing it to be lazy and not get enough voltage back to the gas valve to stay on.
Now this is assuming you have the correct pilot orfice and its not too small like with an LP orfice installed on a NG system. The pressures are differant and the hole is way smaller on LP.
This is a really common problem with multi changeouts of thermocouples. Dusty Pilot burners. y policy has always been to blow it out first after observing the type and kind of flame. Then reexamine it after cleaning it out.
If this helps you please rate me as high as you can. If I have not given you enough information please post back so I can better aquaint myself with you problem. Good Luck!
Posted on Mar 23, 2009
Go to www.grainger.com and look for a "power pile generator" this is a millivolt thermocouple that may be just what you need to make your heater work again
Posted on Nov 12, 2009
Hi, have done this to many times not to know. I will walk you through this. It is good that the pilot is lit. Go to the stat and remove cover. Don't worry as this is a milivolt unit, no voltage or such a small amount you wont even notice as this is why it is called milivolts.Take a small screw driver to remove the next section which is the thermostat and will expose the sub-base where you will find 2 wires connected to it. You may have 2 or 3 screws to take loose to get to this last section. Anyway, if you have a piece of insulated wire laying around, even old speaker wire will work, take it and touch the wire across the 2 terminals and hold. If the furnace comes on, the thermostat is faulty, and you will need to buy a new one. No power to shut down, and simple to change. Cost about $12.00 dollars. Try and get a heat only milivolt stat as they are much less expensive and will have less problems with them. Go to home DEPOT to get one, or O.C.S.H. will also carry them. Don't let the salesman talk you into buying a programable heat and cool stat, 24 volts as they will work, but cost more and you don't need it!! Look around even if you need to go to a wholesale Refrigeration, Air Conditioning, and Heating parts house. Tell them you need one for a unit in some apts you own, and you will pay cash as you want a cash account. They will only ask what job its for, and just tell them your name. This is not illegal and I wouldnt tell you this if it was!! You will still have to pay taxes but will get a wholesale price for it. I am sure it will fire up when you touch the 2 wires and prove stat is bad. For some reason it is not the stat, follow the 2 wires from the stat down to gas valve and jump the same 2 terminals there also. If it fires up, you will have a problem in the wires from the stat to heater and will need to be replaced. I don't think this is the case. But, on the chance it will not fire after you have done all of the steps I have had you do, then you have a faulty main gas valve(MGV) and will need to replace. This is all easy to repair.I am a 100% sure it will fire up when you jump the 2 wires together, and you will need the stat. Please let me know as I will be waiting for an update! Good Luck,
PS When you install the new stat, make sure it is Level.
Posted on Dec 18, 2009
Tips for a great answer:
Jan 30, 2017 | Cozy Heating & Cooling
Feb 18, 2015 | Williams Wall Heaters: 50,000 BTU/Hr...
Feb 11, 2015 | Cozy Heating & Cooling
Jan 08, 2015 | Cozy Heating & Cooling
Apr 05, 2014 | Cozy (W352E) Heater
Dec 20, 2010 | Heating & Cooling
Nov 12, 2009 | Heating & Cooling
Dec 18, 2008 | Heating & Cooling
Nov 08, 2008 | Cozy (W352E) Heater
Dec 16, 2017 | Heating & Cooling
199 people viewed this question
Usually answered in minutes!