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gcrank1
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# Posted: 20 Nov 2024 12:44am - Edited by: gcrank1
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My Dyna Glo 30k btu infrared wall furnace (bought new Dec 2020) has shut off on me a few times the past couple weeks. Each time it has been the same; this account is the most recent.
It started up great, the pilot lit right off and held, then I turned on Low/tile 1, let it burn a bit then lit off Med/#2 & 3, same result, then High/#4 & 5. Ran great.
It took the 52*f cabin to 72* in about 1 hr. We like it warm so I ran it up to 78* and set back to Med.... all was holding well so I set to Low to idle along.
It ran fine for about 15 min then I heard a bit of a roar, looked quick and saw the pilot flame had separated from the nozzle and was out by the thermocouple, then the gas valve shut down due to being too cool at the t-couple.
The safety shutdown worked like it should at the gas control valve.
It was comfy warm so I let it sit about 1/2 hr and tried a restart, no go, Id get enough pilot to act like it wanted to light but not enough gas to hold.
When this happened before I did some online research and most responses were 'replace the thermocouple'. This did not make sense to me as on a cold start up it works fine. In a cold start holding the pilot 'button' down it bypasses the t-couple valve in the gas valve, the pilot lights and holds proper flame, and all tiles/burners run while holding a fine steady pilot with the t-couple activating the gas control valve to open.
I pulled the pilot feed line and jet out, blew the line out then the TINY jet.
Testing the gas valve I confirmed that with the gas on, pilot control depressed, the pilot outlet at the gas control valve fitting flowed gas, control not depressed is no gas.
Put back together, all worked again, guessing the jet had a little plug in it?
Then the shutdown recurred again after a bit at the same Low setting.
This time I also pulled off the feed line from the inlet regulator at the bottom of the unit (btw, I do have proper drip/sediment leg below that inlet) and the gas control valve. Holding it to my mouth and the other end a couple inches from my palm and gave it several strong puffs. What looked like small water droplets sprayed into my palm!
I should mention that in the recent install of this unit into the new cabin I had checked the drip/sed leg and found nothing. I also had blown out every fitting and line I used (most were new for this install).
Put back together and runs fine.
Conclusion: Careful analysis of the symptoms kept me from just replacing what seems to be a good t-couple, which would not have solved the problem (like so many online who did replace and not solve their problem).
Next question is Why the moisture in the line? I expect I will need to pull sections of my supply apart to clean/blow out as this will likely recur 
Fwiw, on lp units with larger pilot jets the droplets may well have passed through. On this the jet is SO small that even a small dia. pin wont enter, I had to use a wire from my brass wire brush and a magnifier. I expect that one of those 'compressed air in a can' would maybe have back flushed it easier.
Hope it isn't moisture coming out of my old 120 Gal cylinder but where else could it be coming from?
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Brettny
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# Posted: 20 Nov 2024 10:28am
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You need a drip leg. Are you useing any type of rubber or stainless line in the system?
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Fanman
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# Posted: 20 Nov 2024 11:35am
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Is a new tank, and if so, was it purged and methanol added? My tank arrived vacuum purged, and the you're supposed to add some amount of methanol to absorb moisture. If it's vacuum purged, you just let the vacuum suck in the methanol. It's just like putting dry gas in your car and in fact I used automotive dry gas, which is also just methanol.
I have also heard of moisture being introduced while filling on a rainy day, though I've never observed it.
But your "bit of a roar" and pilot flame separating from the jet makes me wonder if you have a bad regulator, too-high gas pressure might do that.
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FishHog
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# Posted: 20 Nov 2024 12:08pm
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take some fine sand paper and gently clean the part of the thermocouple that the fire is on. Small amount of bulidup/dust etc. can change the resistance and cause those issues. Was out in Alberta this spring at my brothers house and the furnace kept going out. That was my first step as its easy and its still running normal today.
If that doesn't work, then the above suggestions are good next steps. But switching to another tank and purging the line would be step 2 for me.
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gcrank1
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# Posted: 20 Nov 2024 02:58pm - Edited by: gcrank1
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Old 120gal/420#? upright cylinder, had it refilled June of 2022. I bought it used with about 40% and ran it with this heater through winter '21-'22 with no prob.
Ran it winter '22-'23 and '23-'24 with no prob.
In the back of my mind this past April? just as we were prepping to dismantle the old shack I sorta remember it 'popped off' but I was pulling it out anyway (so much has happened since then and Ive totally forgot it).
Yes, it has the proper (emphasis Proper) drip/sed leg.
And yes, there is a new rubber line from tank to the black iron at cabin wall.
The pilot flame is perfect when lighting up and initial running, even 2+ hours, then the pilot gets the flame separation (like lighting a cutting torch without enough acetylene cranked in) which isn't hot enough so the t-couple doesn't keep the gas valve open.
Im wondering if over time the piping has had enough internal condensation due to this being a rec use cabin and the heating/cooling cycles it goes through that the delivery piping and the pilot delivery tube plug the jet with a droplet.
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gcrank1
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# Posted: 21 Nov 2024 12:48am
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Went today, cabin at 44*f, unit fired right up and ran it on High for 1 hr, got to 72*. Set it down to Med and it ran for another 1hr 15min and shut down. Temp was a nice 77* though.....
Pulled the pilot delivery tube, the pilot jet and the delivery tube to the gas control valve.
The jet looked good but I ran the brass wire anyway.
Pushed a length of weed-wacker line through the pilot tube (snug fit), nothing found, then puffed on it too.
The main delivery tube (the one I got the spray of droplets from) is much bigger so I ran the line through and put a cloth patch on then pulled through; repeat 4x. Nothing seen on the patch.
Blew out the gas control valve.
Reassembled and turned on gas then ran the sniffer at all the disturbed fittings. All good.
I fully expected it to light off but No.....let it sit 1/2hr and the retry failed like it isn't getting enough gas to pilot up. (btw, this should have nothing to do with the t-couple as the push down pilot button bypasses/opens the gas control).
Bet if I went tomorrow it would fire right up again.
Next time Im going to run until shut down and quickly unhook the feed line and hook up my 18k btu 'blue flame' unit. Depending on how it runs will tell me if the regulator is ok.
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FishHog
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# Posted: 21 Nov 2024 12:40pm
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that should be a good regulator test. Any chance it has an Oxygen sensor that is tripping off? Could be faulty, or you could actually be reducing the O2 enough during your initial warm up that its doing it job. Not sure how long they take to reset after tripping. Just brainstorming.
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gcrank1
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# Posted: 21 Nov 2024 03:18pm
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Have considered Ox sensor; on this unit it is a pair of holes at the mixing tube base, right above the pilot jet output. The sizing of the jet/orifice and those holes is 'finely calibrated'; ie, if the Ox is reduced the burn of the pilot flame is improper, the t-couple cools and the Gas Control Valve shuts down.
This can be tested on a good pilot light by covering one hole, even a little, and seeing the flame go 'cold' followed by the shut down.
This is also a good test of a gas control safety valve proper function.
So there is no reset 'time' on this type other than doing some fresh air exchange, at which the pilot should relight as normal.
In my case it seems the gas flow to the pilot is reduced, resulting also in a poor 'cold' pilot flame which does shut it down as intended.
If my other heater (#2) runs fine it will verify the outside tank reg is ok and kinda point to unit #1's gas control valve? I once saw (and haven't re-found) an online vid where the guy pulled a GCV apart on the bench; iirc he found crud inside. It wouldn't take much of a goo to partly block the pilot feed tube at the GCV outlet to reduce the gas flow enough to cause a cold pilot. Then after sitting ? long the 'slug' drips back off and the thing runs fine again?
This is old school 'mechanical controls' unlike new fangled computer board so I should be able to sort it out.....
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gcrank1
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# Posted: 21 Nov 2024 05:18pm - Edited by: gcrank1
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I found it! The GCV refurb anyway....
YouTube
'Mr Heater wont light' (repaired)
by Jeff Rodrigues
Disassembly, refurb and reassembly; imo pretty well done. He found a broken sealing washer plugging the pilot outlet and A Bunch of oily residue.
Im gonna do this!
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Brettny
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# Posted: 22 Nov 2024 10:24am
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Some rubber lines can leach oils out into the propane. In portable buddy heaters. There known to cause issues.
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gcrank1
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# Posted: 22 Nov 2024 01:13pm
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From what Ive seen online about the rubber lines the issue seems to the diff between 'low pressure' lines and 'high pressure' lines.
On the Buddy's the regulator is in the unit so from the tank to unit regulator is high tank pressure gas. If you use a low pressure grade line the high pressure can/does leech (squeezes) out the 'oils' from the rubber which then is carried to the unit reg and the lines inside. Mr Heater has high pressure lines of a diff compound but if you want to use the low pressure lines you should use their inline filter.
It is said that if you are putting a line in after the regulator (typically at 11"WC/ less than 1/2psi)) that low pressure doesn't leech the oils. Of course there is no downside to using high pressure lines there too.
Btw, the lines will have that info stamped into the rubber and it may be hard to find or see.
That said, early on with my trouble I did disconnect my new line at the tank reg (easy tapered fitting), put a clean rag on and blew it out from inside; got nothing.
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gcrank1
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# Posted: 23 Nov 2024 08:09pm - Edited by: gcrank1
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Opening day of the WI Gun Deer Hunt; we don't hunt anymore but went to the cabin for the day, 38*f outside/42* inside.
As before the heater fired right up, set it on high/5 tiles and let it run. At 2.5 hrs it sputtered and was about to poof off when I shut it off. Also as before, after a short rest, I depressed the pilot button and got only the miserable puff like hardly any gas.
We were plenty snug but I wanted to see if the old blue flame would run so I did a quick disconnect of the flared fitting and swapped it in. Started and ran just fine.
Seems fuel delivery from tank through reg and supply line is ok.
While Joyce watched the 'deer' meadow out our new cabin BIG windows I tore once again into the problem child. Disconnected the unit input feed line both top and bottom then all the lines, pilot and 3 burner lines and the t-couple fitting.
With just a bit of messing about the GCV came out.
I blew into the input port while turning the control to pilot and depressing it, got nothing out the pilot port! Well, of course the pilot wont run!
So I pull the bottom t-couple solenoid cover off, pull out the solenoid and replaced the cover. Plugged the t-couple hole and did the puff test (no depressing needed, the path was clear right through on the pilot setting. Was it a sticking solenoid and seal? Has to work now.
Blew out all the lines (I had my portable air bottle and tip) and reassembled without the t-couple/solenoid Safety Valve (for function TESTING ONLY).
Hooked up the gas line again and tested for gas flow through the unit input, got a good flow.
Reassembled.
Pilot Wont Light!
Pulled the jet, could see through it but blew it out anyway; reinstalled and No Go.
This Is Nuts
Im about to 
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paulz
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# Posted: 23 Nov 2024 08:55pm
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Wish I could help but you lost me a long time ago and I'm no LP guru.
Here's a bump anyway.
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gcrank1
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# Posted: 23 Nov 2024 09:49pm
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Paul, a motorcycle carb is more complicated! Plus you have to deal with proper compression as well as spark at the right time.
These class units are sorta like turning on a water hose and triggering the nozzle, the gas is supposed to come out (pilot) at which point the igniter sparks and there is the flame. Once that is lit you adjust the knob to low, med or high.
The safety stuff is extra, once bypassed its down to basic flow and light it up.
Except......mine.....
Wish I had brought the jet home to soak in some carbon remover; even though I can see light and have poked that hole with a fine brass wire I wonder if it is carbon'ed up, which reduces the dia, and when it heats up the hole gets even smaller???? There sure is enough gas in the pilot feed pipe behind the jet.
Btw, seems just a jet is not available, ya gotta buy the whole igniter assembly
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darz5150
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# Posted: 23 Nov 2024 10:16pm
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I had to clean out one of mine with a Q tip and alcohol. It was having symptoms like yours.I have another blue flame one, that if you run the vacuum or sweep close to it, somehow dust triggers the OD safety. The pilot goes out, then when I try to relight it. The flame sputters. I blast it with a portable air tank and a custom bent copper line to reach around the glass without taking anything apart.
I have 2 blue flame and 2 ceramic heaters.
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gcrank1
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# Posted: 23 Nov 2024 10:40pm
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All the Q-tip/alc does is clean the mixing tube above the jet, and yes, it can get fouled and mess it up. Ive done and redone mine several times thought this misadventure.....easy enough to do so why not.
Think that was the 1st thing I did, plus pull the actual jet and probe it; it screws into the tail end of the mixing tube and typically has the pilot feed line attached at the rear.
The hole is Really SMALL
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Fanman
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# Posted: 24 Nov 2024 07:48am
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I've used carburetor cleaner to clean gas jets, then blow it out with compressed air. But hold it good, a tiny brass orifice can be tough to find after a blowgun has launched it across the room.  Poking at them can damage them, a burr could disturb the gas flow which might affect how much air is drawn into the mixing tube. Using a brass wire is better but if it gets stuck you're screwed.
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paulz
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# Posted: 24 Nov 2024 11:08am
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Quoting: gcrank1 There sure is enough gas in the pilot feed pipe behind the jet.
So you have gas flowing out the feed pipe and jet is clear. won't even light with a match?
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gcrank1
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# Posted: 24 Nov 2024 12:36pm - Edited by: gcrank1
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I hear ya on 'don't launch the jet into the cosmos nor especially the black hole' that seems to surround anyone working on stuff.....
I could go today and it would likely fire up just fine, then run a couple hours and slowly drop off until the pilot gets too cool to hold and (with the t-couple safety working) will shut down.
I follow the recommendation to let it sit a bit and try to relight the pilot and only minor flame spirts, as in not enough gas flow.
I can disconnect the pilot feed pipe, turn on the valve and what seems to be more than enough gas to run a pilot pumps out.
So that would mean a partially plugged jet.....but I can see light and have carefully probed it out.
Ive hooked up the swap in back-up heater for the rest of our stay (only day trips), messed with unit #1 until out of ideas, then hook it back up just before we go home.
Next time we go it fires up fine. That really tells me the heater works right so it must be gas supply?; but when it shuts down and I swap in unit #2 it runs fine.
BUT, yesterday I think unit #2 was burning lower toward the end. Could I be getting poor vapor development in that big 120gal tank (its about at 30%)
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paulz
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# Posted: 24 Nov 2024 01:36pm
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Have you tried it with a 5 gallon tank?
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ICC
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# Posted: 24 Nov 2024 01:52pm
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Quoting: gcrank1 Could I be getting poor vapor development in that big 120gal tank (its about at 30%)
A 120-gallon tank should have no difficulty supplying gas to a single heater unless the temperature is close to -40 F or C.
Just FYI in general here's a table for temperature & BTU delivery on a variety of cylinder sizes designed to be mounted VERTICALLY. The typical horizontal tanks can deliver many more BTU's at any temperature, down to -44 F when it stops being a gas. Horizontal tanks have a larger surface area of propane to evaporate from.
Do you have any other propane-burning devices that can operate at the same time as the problem heater?
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gcrank1
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# Posted: 24 Nov 2024 04:05pm
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That has been my understanding Izzy.
Im gonna put another flared fitting on my supply line T inside (3/8" black iron pipe) so I can easily hook up a bbq tank, reg and line to give a go.
And I have a flare cap to seal it off in between.
Last spring, when I think I remember the 1st time of this same problem, I had a diff 2 stage reg set up.
This year I used a diff 2 stage and Ive even swapped it out with another one (none new but all the same result).
The most common denominator left in last spring and now is the tank. If the heater(s) run ok on the bbq tank I'll have to be talking to the lp supplier that filled the big one.
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gcrank1
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# Posted: 25 Nov 2024 08:00pm - Edited by: gcrank1
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Soooo
Remember a couple days ago I reported I 'disabled' the safety solenoid in the gas control valve (I don't recommend you do this, I did it for testing purposes only).
Also remember unit still wouldn't light up.....
Today, like usual, upon our return it fires right up (sans the t-couple powered safety). Nice pilot, burners/tiles lit up.
By eliminating anything to do with the safety valve I could monitor what happens at the point the pilot went cool (and would normally shut it all down, but now the burners/tiles would continue to run).
And it did, at about the same 2.5hrs out; the pilot flame lifted off the tip and there was that telltale bit of a roar (kinda like a propane torch), the tiles kept running and the pilot flame held well out from the mix tube tip.
Darz and Fish get the prize, problem is at the Oxygen Depletion Sensor, or rather the oxygen level, the sensor is working like it should.
The clue: The unit, as built, would run about 2.5hrs and shut down.
With the safety disabled it would run about 2.5hrs.
Same.
We would leave and upon return it would start and run fine.
Here is what happens: Normal oxygen level is about 21%. If you don't have enough fresh combustion air incoming, and a tight build, it is depleted in the burn. When it hits about 19% the balance of fuel/air is not correct and the pilot flame cools enough to not keep the t-couple sending low voltage to the safety gas flow shut off in the gas control valve.
Yes, the reduced oxy level....the very reason ODS have been required for Indoor Units. Note: OSHA regs consider below 19.5% to be deficient.
This exactly why one should never disable the safety shut down.
This is also why more than just a CO and smoke detector may be needed. As long as the ODS on the unit works the gas will be shut off; that is to say, the default of the gas control valve IS OFF, it returns to off if the pilot wont run.
I Need More Combustion Air!!! 1 sq in per 1000btu, in my case that is 30si or a 1 inch opening in a 30" tall window; though it is preferred the intake combustion air come from 'down low'.
So, with a heater, water heater, lp fridge, etc with a standing pilot, if you experience the pilot flame lifting from the tip of the tube and shut down you may be able to just clean the mix tube (as Fish questioned and Darz said how), vacuum out and such, but if that is all clean you may have a low oxygen level, especially if it works well after a good air exchange.
Fwiw, I researched this online repeatedly, different questions, etc and did Not find this particular explanation of the 'lifting flame' until tonight After I had concluded it today.
Now I know my unit inside and out!
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Malamute
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# Posted: 25 Nov 2024 08:10pm
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Interesting. I came back to see what was the recent news or diagnosis.
I havent had that exact issue with a propane heater, but my airtight woodstove was depleting the oxygen in my cabin. It had a fresh air intake set up so it could be ducted in. I made a hole in the floor under the intake and put a metal duct tube down with screen over it to keep varmints out. It gets air from the crawl space under the cabin.
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ICC
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# Posted: 25 Nov 2024 08:34pm - Edited by: ICC
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....a reminder as to why a direct vent space heater, or any appliance that burns fuel, is best.
Glad you sorted it out and safely.
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FishHog
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# Posted: 26 Nov 2024 07:25am
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Well glad you figured it out. Amazing how such a simple thing can have so many different potential issues. Trouble shooting is nothing more than trial and error until you narrow it down to the issue.
But the upside is you gain a great understanding and future issues are easier to deal with.
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paulz
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# Posted: 26 Nov 2024 08:56am - Edited by: paulz
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Yes, good job figuring it out. So the upshot is it was being run in an airtight cabin with no ventilation? Lack of oxygen (for you as well). What about carbon monoxide?
Probably not helping the vertigo. I might be facing the same thing with my non fresh air wood stove. Luckily in a drafty cabin and I go outside to pee every half hour.
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gcrank1
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# Posted: 26 Nov 2024 09:06am
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Have 2 CO detecters, 1 hardware store model and 1 super sensitive that we take back&forth from home.
Was cracking a window but by the specs not enough obviously....for my 18k btu it had been ok but for the 30k I should have doubled it (dope slap); ie, 1"x30" gap, or variations of that to suit your windows.
Fwiw, a CO unit will do Nothing as Oxy level alarm. With a properly functioning ODS a Oxy sensor may not be necessary, but.....
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gcrank1
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# Posted: 26 Nov 2024 07:10pm - Edited by: gcrank1
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Today I verified that I had no leaks in all the fittings with my 'sniffer', a leak check is a requirement for installs or ANY service that breaks a fitting.
As expected it lit off nicely.
After a test burn I verified the ODS functioned by turning it to low and closing off the air intake holes in the mixing tube. Within seconds the gas control valve SNAPPED closed and unit shut down.
This test is required after messing with Anything to do with the safety system.
Be aware that some jurisdictions require a licensed tech to do any of this stuff; some even for the initial installation and even replacing a t-couple.
Also be aware the insurance company Will likely consider any 'modifications' of the system a reason for denying a claim.
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paulz
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# Posted: 28 Nov 2024 08:33am
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Quoting: gcrank1 Went today, cabin at 44*f, unit fired right up and ran it on High for 1 hr, got to 72*. Set it down to Med and it ran for another 1hr 15min and shut down. Temp
Happy Thanksgiving! Temps, and acclimation are a funny thing. Here on the Northern California coast we have it pretty easy, a few freezing winter days and the ocean breezes usually handle summer heat waves.
I have had times when getting the cabin into the low 80s felt great for just laying around. Like you, normally 70s does it. This morning I woke up to high 60s (38 outside), went out and grabbed some wood (night log had burned out) and actually was fine with that, guess the winter acclamation is kicking in.
Fires going though, back to the 70s.
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