Thermocouple failures

kevin coppinger_4

that I used a American Water Heater to heat a slab. The load is 18,000btu. It is a closed system and uses an 3" b-vent to vent through the roof. The water heater input is about 30K and is LP. The install is just over a year old. The heater has gone through 3 themocoulples in the last three months...each time it is carefully changed to ensure that it is properly installed and running well, the way it is set up it does make it hard to mess it up...I am just wondering here what the deal is? What should I do? Anything to look at? Test?I am about ready to chuck the whole thing...One thing that I did notice is the tray does have a good deal of "dirt" on floor...is that normal? tia,kpc

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GEO_3

This must be the old sryle wh. Did you take an actual milivolt reading before and after? I've also seen ECO switches reset themselves. I've also gone through 3 thermocouples to get s good one. If your new thermocouple is reading 20 MV or better under a load you should be allright see if the flame is hitting the top 3/8 in of the tip. If its under 20 mv the pilot could be weak or the safty is drawing to much power and you'll have to replace the control. If it's the ECO turn the temp down slightly and see if it cures it. Hope this isn't to basic dut I know there are alot of people out there that don't have millivolt meters. George

Arthur

Thermocouples

Check that the pilot flame is tooo highh and is burning the tip off the thermocouple(s). If it holds in, in say 5 sec thats a sure sign the pilot is toooo hiii, If a thermocouple hold in at about 15-20 secs that a usually a sign the flame is about right.