Direct vent gas heater - pilot light

[Ashful]

Went out to the garage this morning, and found it in the mid-40's. Not good... I have a few refrigerators out there that don't like seeing much below 50F.

I checked the direct-vent heater, and found it had gone out during the night. I re-lit the pilot (hold gas knob button down, click gas grill-style igniter button), and the pilot relit without issue. However, I can't get it to stay lit when I release the button.

Troubleshooting manual states:

1. Once pilot is lit, the gas control knob must be held down long enough to energize the pilot circuit (15-20 seconds).
2. Pilot flame is small or yellow. The pilot flame can be viewed through the lower right view window while the control knob is depressed. If the flame is small or yellow in color then the pilot orifice should be cleaned. Cleaning pilot orifice
3. If pilot flame is adequate then the thermocouple should be replaced.

My figuring is that, since it actually went out while running during the night, I can probably skip right to step 3. Any expert opinion out there?

Also, to my completely untrained eye, it looks like there might be a weird hole burned in the little shield that directs the pilot toward the thermocouple. Is this even possible? I can only see it when lit, as it glows thru the little sight window.

edit: I should add, it's an Ecotherm MV-130.

 

[festerw]

I've had luck taking some 200+ grit sandpaper and cleaning up the thermocouple on my heater. It stopped working during a cold snap 5 years ago and I tried that as a stop gap until I could get a new one. The new one is still sitting on the shelf.

 

[Ashful]

Okay, I’ll pull it and give that a try. Thx!

 

[jatoxico]

DAKSY knows these gas heaters doesn't he?

 

[Ashful]

Dunno. Haven't seen him in months, but maybe I'm just watching the wrong threads.

Paging @DAKSY

 

[Wooden Head]

Went out to the garage this morning, and found it in the mid-40's. Not good... I have a few refrigerators out there that don't like seeing much below 50F.

I checked the direct-vent heater, and found it had gone out during the night. I re-lit the pilot (hold gas knob button down, click gas grill-style igniter button), and the pilot relit without issue. However, I can't get it to stay lit when I release the button.

Troubleshooting manual states:

1. Once pilot is lit, the gas control knob must be held down long enough to energize the pilot circuit (15-20 seconds).
2. Pilot flame is small or yellow. The pilot flame can be viewed through the lower right view window while the control knob is depressed. If the flame is small or yellow in color then the pilot orifice should be cleaned. Cleaning pilot orifice
3. If pilot flame is adequate then the thermocouple should be replaced.

My figuring is that, since it actually went out while running during the night, I can probably skip right to step 3. Any expert opinion out there?

Also, to my completely untrained eye, it looks like there might be a weird hole burned in the little shield that directs the pilot toward the thermocouple. Is this even possible? I can only see it when lit, as it glows thru the little sight window.

edit: I should add, it's an Ecotherm MV-130.

Is this natural gas or propane?

 

[Ashful]

Propane. Sorry for not mentioning that.

Is the “thermocouple” on these a true thermocouple conducting an electrical signal, or more like those old Autometer mechanical temperature gauges, which are just conducting heat along a heavy copper conductor? If the latter, that would explain why it is shutting off when the garage is extremely cold, and never did before.

 

[Ashful]

I've had luck taking some 200+ grit sandpaper and cleaning up the thermocouple on my heater. It stopped working during a cold snap 5 years ago and I tried that as a stop gap until I could get a new one. The new one is still sitting on the shelf.

Thank you for posting this. I was in the middle of another project the last two days, but took an hour this afternoon to take it apart and do this, and it worked! It is running happy, right now. Getting that thermocouple out was a bear, as they pack the pilot line, igniter, and thermocouple nuts so close to one another that a normal fitting wrench can’t get at them. Gonna let the garage get up to temp, then shut down and check for leaks with soapy water. Had to actually remove main line to burner, to get igniter out, to get thermocouple out. Yeah... one of those jobs.

 

[festerw]

Thank you for posting this. I was in the middle of another project the last two days, but took an hour this afternoon to take it apart and do this, and it worked! It is running happy, right now. Getting that thermocouple out was a bear, as they pack the pilot line, igniter, and thermocouple nuts so close to one another that a normal fitting wrench can’t get at them. Gonna let the garage get up to temp, then shut down and check for leaks with soapy water. Had to actually remove main line to burner, to get igniter out, to get thermocouple out. Yeah... one of those jobs.

Yea mine was about the same way which is why I haven't bothered putting the new one in.

 

[Wooden Head]

Propane. Sorry for not mentioning that.

Is the “thermocouple” on these a true thermocouple conducting an electrical signal, or more like those old Autometer mechanical temperature gauges, which are just conducting heat along a heavy copper conductor? If the latter, that would explain why it is shutting off when the garage is extremely cold, and never did before.

The reason I asked is I had the same problem. I bought a new thermocouple and installed it. Did not fix the problem. I went out and checked the gauge on the tank for the second time. It read 80%. I could not remember the last time the tank was filled. Got a pipe wrench and banged on the side of the tank. Heard what sounded like a spring releasing and the gauge now read 0. So now I have an extra thermocouple and a $85 charge for an unscheduled tank fill.

 

[Ashful]

The reason I asked is I had the same problem. I bought a new thermocouple and installed it. Did not fix the problem. I went out and checked the gauge on the tank for the second time. It read 80%. I could not remember the last time the tank was filled. Got a pipe wrench and banged on the side of the tank. Heard what sounded like a spring releasing and the gauge now read 0. So now I have an extra thermocouple and a $85 charge for an unscheduled tank fill.

Doh! Good to know. I used to have a well pump gauge that behaved that way.

 

[fbelec]

if they charged you 85 for a unscheduled delivery where were they on the sched time?

 

[Wooden Head]

if they charged you 85 for a unscheduled delivery where were they on the sched time?

There is no schedule for the shop tank. I need to inform them that it needs attention on their schedule for the house tank. I don't use much in the shop, so not to be charged the same per gallon for both and not incur a tank rental charge, this is how I have to do it,