EcoTherm LP space heater model MV 120

[Nitai]

I have this space heater (quite a few of them actually) because I am off the grid. It seems that Bosch used to own this company but does not anymore and last time I had a problem after hours of agonizing phone conversations I ended up speaking with a woman in Canada who spoke only french:?. Anyway my problem now is that the knob seems to be stuck.

To ignite the pilot you must turn the knob slightly counter-clockwise and push it down. After it ignites  you must let it come up and turn it quickly clockwise, passing the "off" and turning about 180-degrees. My knob gets stuck at off and the pilot just putters out. Any suggestions?

[dkpd1581]

The knob you are describing and the method of turning it on sounds exactly like a standard intermittent pilot gas valve.  That it does light when pressed down and on Pilot lets us know that the valve is good, that the ignitor is good, and that you have gas flow. 

What sounds to be the simple problem is the flame proving device - most likely a thermocouple or a thermopile is going bad. When you turn it to LIGHT passing OFF to ON may be an indication that the thermocouple is dirty, slow to register/prove the flame, or needing replacement.  If it is in fact a thermocouple, a replacement part can be obtained for just a few dollars at any Lowes, Home Depot, Hardware store, or even Walmart.  First try allowing the pilot flame to stay lit for about 45 seconds before turning the knob to ON.  An old or slow thermocouple may need a longer warm up time to generate enough millivolts to keep the gas valve coils open.

Another issue is that the aluminum gas tube feeding the gas to the orifice or Spud(s) - brass nut(s) that feeds the gas to the flame - is dirty.  Check for soot, dust, cobb webs, spider nest/egg sack, or even the possibly deceased spider in the tubing/orifice. That will require you to root around in the heater's burner compartment, clean the area, and even GENTLY run something smaller than the hole(s) in the spud(s) into the orifice.

Lastly, make sure that your LP tank is full and providing enough pressure to the burners.

Best of Luck

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