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[GMCnet] 2 furnaces in one day [message #269443] Mon, 12 January 2015 07:05 Go to next message
Ek_Lektro is currently offline  Ek_Lektro   United States
Messages: 167
Registered: March 2011
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I have to wonder, is there such thing as a bad batch of propane?
The Suburban (NT30 M) started misbehaving yesterday, requiring 3 or 4 tries to light,
and then finally today refused to light at all. The fridge and stove-top both work without issue,
and of course i checked battery voltage (12.6v), and tightened up the ground, since the spark seemed inconsistent at first. well now i get a bright consistent spark, and no propane fumes, which has me thinking its either the gas valve or control board(?)
So then i took a break and went over to the Eleganza to have some dinner... and the furnace (DuoTherm) won't light over there, either! Other than pure coincidence, the only commonality is that they're both hooked up to 5 gallon LP bottles (BarBQ style), since the Eleganza isn't currently driving; and i had just converted the Birchhaven over to a compartment with swappable 5 gallon bottles... which worked great for the first few days.. then developed this problem.
Curious what the forum has to say about this, and what my first testing steps should be. I can get another bottle of propane filled tomorrow, from another store, for what its worth...
Thanks in advance for any feedback!
cheers,
Greg / SolarSonic 26 foot and 21 foot "fleet".. currently with flat feet / Los Angeles
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Re: [GMCnet] 2 furnaces in one day [message #269448 is a reply to message #269443] Mon, 12 January 2015 09:03 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
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1st. Have both furnaces been fully functional before this effort?
2nd. Perhaps low gas pressure? Just a guess, but a the outside temperature goes down, the gas pressure drops.
No fun to fiddle with a furnace when you need one.
Tom, MS II


2012 Phoenix Cruiser model 2552 KA4CSG
Re: [GMCnet] 2 furnaces in one day [message #269458 is a reply to message #269443] Mon, 12 January 2015 10:51 Go to previous messageGo to next message
77Royale   United States
Messages: 461
Registered: June 2014
Location: Mid Michigan
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Does the stove light and stay lit without issue? If it does the could possiby eliminate the issue of bad propane.

Is the fan running and coming up to speed? you said you had intermittant spark a day ago, which could be a sticky sail switch. My understanding if the sail switch does not open with the blower running, it will not allow the spark to happen. you said it took a few times yesterday. So that could be an issue. If there is no spark, it will lock out and no gas will flow.

Is there a chance a hose going to the furnace is kinked?

The other "easy stuff" Do you have gas or did it all leak out? The first question will take care of that. Stove stay on?

I had an issue a few weeks ago with my NT30 M Lighting but only for a second then turning off. Turned out it was bad a high temp limit switch for 22 bucks or so. Its posted on the board here. In that same thread there are links to the trouble shooting guides which were helpful to me to understand the sequence of everything.

Prior to limit switch, I had read that when you shut the service valve off, and then turn it on, you may need to purge some of the air out of the line, Like lite the stove for 20-30 seconds, Then attempt to light the furnace. This was very helpful as well..










77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy. Mid Michigan
Re: [GMCnet] 2 furnaces in one day [message #269460 is a reply to message #269443] Mon, 12 January 2015 10:56 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
Messages: 4508
Registered: April 2011
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Senior Member
Ek_Lektro wrote on Mon, 12 January 2015 07:05
I have to wonder, is there such thing as a bad batch of propane?
The Suburban (NT30 M) started misbehaving yesterday, requiring 3 or 4 tries to light,
and then finally today refused to light at all. The fridge and stove-top both work without issue,
and of course i checked battery voltage (12.6v), and tightened up the ground, since the spark seemed inconsistent at first. well now i get a bright consistent spark, and no propane fumes, which has me thinking its either the gas valve or control board(?)
So then i took a break and went over to the Eleganza to have some dinner... and the furnace (DuoTherm) won't light over there, either! Other than pure coincidence, the only commonality is that they're both hooked up to 5 gallon LP bottles (BarBQ style), since the Eleganza isn't currently driving; and i had just converted the Birchhaven over to a compartment with swappable 5 gallon bottles... which worked great for the first few days.. then developed this problem.
Curious what the forum has to say about this, and what my first testing steps should be. I can get another bottle of propane filled tomorrow, from another store, for what its worth...
Thanks in advance for any feedback!
cheers,
Greg / SolarSonic 26 foot and 21 foot "fleet".. currently with flat feet / Los Angeles
If it was cold, the regulator might have froze. Not sure if it is water in it or the parts can't move freely when they get cold. My brother thought he was out of propane when his furnace stopped working. Checked later during the day after the temperature came up a little and there was plenty of propane. Relit the furnace and all was well. The guy that drove the truck that filled the tank later that winter said it happens a lot.
Re: [GMCnet] 2 furnaces in one day [message #269462 is a reply to message #269443] Mon, 12 January 2015 11:16 Go to previous messageGo to next message
77Royale   United States
Messages: 461
Registered: June 2014
Location: Mid Michigan
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Senior Member
The original post Sig line indicates Los Angeles, I think. Hope it wasnt that cold there, but who knows.



77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy. Mid Michigan
Re: [GMCnet] 2 furnaces in one day [message #269472 is a reply to message #269443] Mon, 12 January 2015 12:00 Go to previous messageGo to next message
Ek_Lektro is currently offline  Ek_Lektro   United States
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Registered: March 2011
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> 1st. Have both furnaces been fully functional before this effort?

Yes, they've both been working "decent" recently, but of course with the usual kinks that i've wrestled from time to time over the years. (replaced fan motors and sail switches on the DuoTherm, but I don't recall ever having to do anything with the Suburban other than blow out the burner with compressed air periodically). One kink with the Suburban: I"ll wake up sometimes to hear it cycling with the fan coming on for 6 to 10 seconds, then shutting off. usually this is when i'm down to 11.7 to 12.0 volts, so i hadn't pursued this issue yet.

> 2nd. Perhaps low gas pressure? Just a guess, but a the outside temperature goes down, the gas pressure drops.

What's the tool needed to measure this? And what should the pressure be, coming out of the regulator?

i know that the fridge flame has been a bit yellow-ish, but i was attributing this to a dirty burner since the fridge had been unused for a few years, and we just started using these appliances in the past 8 days actually... Rebuilding the Birchhaven!

> Does the stove light and stay lit without issue? If it does the could possiby eliminate the issue of bad propane.

yes it does... and the flame is a good color blue

> Is the fan running and coming up to speed?

yes it is...


> you said you had intermittant spark a day ago, which could be a sticky sail switch. My understanding if
> the sail switch does not open with the blower running, it will not allow the spark to happen. you said it took a few times yesterday. So that could
> be an issue. If there is no spark, it will lock out and no gas will flow.

i think i solved the intermittent spark problem, after i tightened up some wiring.
So now there's spark, and the fan comes on... (in both of these furnaces)

>
> Is there a chance a hose going to the furnace is kinked?

doubtful, but i'll double check

>
> Its posted on the board here. In that same thread there are links to the trouble shooting guides which were helpful to me to understand
> the sequence of everything.

i'll look for that, thanks. how long ago was the thread? i suppose i'll search "furnace trouble shooting"...

> If it was cold, the regulator might have froze.

hey, Its been a bit chilly here in Los Angeles lately, but fortunately not the kinda cold i know from my years in Boston!

Thanks everybody,
Greg

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Re: [GMCnet] 2 furnaces in one day [message #269473 is a reply to message #269443] Mon, 12 January 2015 12:20 Go to previous messageGo to next message
Chris Tyler is currently offline  Chris Tyler   United States
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Location: Odessa FL
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Use a manometer to measure the pressure. A dial type is easier. Remove one of the range burners and attatch at the manifold with hose.
Should be 11 inches of water column as I recall. You can also light another buner if you are careful to measure running presure to check foir a sticking reg. Sometimes the statc pressure will be ok, but drops under load
Manometer is useful for checking for gas leaks too...shut off gas and see how long pressure is maintained
Nice thing is, they are cheap.

Your reg may or may not be adjustable


76 Glenbrook

[Updated on: Mon, 12 January 2015 12:22]

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Re: [GMCnet] 2 furnaces in one day [message #269479 is a reply to message #269443] Mon, 12 January 2015 12:48 Go to previous messageGo to next message
77Royale   United States
Messages: 461
Registered: June 2014
Location: Mid Michigan
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Suburban Furnace Irradic Ignition was the title of the thread. 2 or 3 pages back.

I downloaded the manauals and trouble shooting stuff both off the internet and I think Bdubs site has them, Either way, the link is in that old thread.

This is probably a silly question but is the valve open on the furnace? Its been overlooked before. Id try to open and close it a few times to see if perhaps something is sticky in there.

Also another idea. Are you either plugged into shore, or can you try to start the furnace with the engine running. This is just makeing sure you have enough power to run the blower fast enough. I know you said you metered it, but its worth a quick try.

Once my battery was a bit low, and the blower would run, fast enough I thought until there was no spark. Plugged in shore and it fired right up.

The blower needs 75% speed to kick the sail switch.



77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy. Mid Michigan
Re: [GMCnet] 2 furnaces in one day [message #269537 is a reply to message #269479] Mon, 12 January 2015 21:19 Go to previous messageGo to next message
k2gkk is currently offline  k2gkk   United States
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Senior Member


Sent from my iPad

> On Jan 12, 2015, at 12:48, Wayne Rogewski wrote:
>
> Suburban Furnace Irradic Ignition was the title of the thread. 2 or 3 pages back.
>
> I downloaded the manauals and trouble shooting stuff both off the internet and I think Bdubs site has them, Either way, the link is in that old
> thread.
>
> This is probably a silly question but is the valve open on the furnace? Its been overlooked before. Id try to open and close it a few times to see
> if perhaps something is sticky in there.
>
> Also another idea. Are you either plugged into shore, or can you try to start the furnace with the engine running. This is just makeing sure you
> have enough power to run the blower fast enough. I know you said you metered it, but its worth a quick try.
>
> Once my battery was a bit low, and the blower would run, fast enough I thought until there was no spark. Plugged in shore and it fired right up.
>
> The blower needs 75% speed to kick the sail switch.
>
>
> --
> 77 Royale
> Mid Michigan
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Re: [GMCnet] 2 furnaces in one day [message #269550 is a reply to message #269473] Tue, 13 January 2015 00:42 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Read here
http://www.gmcmhphotos.com/photos/propane-system-leak-check/p5241.html
Erf

On Monday, January 12, 2015, Chris Tyler wrote:

> Use a manometer to measure the pressure. A dail type is easier. Remove
> one of the range burners and attatch at the manifold with hose.
> Should be 11 inches of water column as I recall. You can also light
> another buner if you are careful to measure running presure to check foir a
> sticking reg. Sometimes the statc pressure will be ok, but dropss under
> load
> Manometer is useful for checking for gas leaks too...shut off gas and see
> how long pressure is maintained
> Nice thing is, they are cheap.
> --
> 76 Glenbrook
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>


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Re: [GMCnet] 2 furnaces in one day [message #269559 is a reply to message #269443] Tue, 13 January 2015 08:57 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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I have not used it on the furnace, but have done some other propane pressure testing with this tool:

http://www.amazon.com/Yellow-Jacket-78060-Complete-Test/dp/B0016H12KS/ref=sr_1_1?ie=UTF8&qid=1421160913&sr=8-1&keywords=propane+pressure+t ester

I know you can make your own, but that item above sure does work nice.

there is cheaper one on amazon that I see now, but the one I own is the above link:

http://www.amazon.com/General-Tools-Instruments-GPK035-Pressure/dp/B001TOFRNG/ref=sr_1_2?ie=UTF8&qid=1421160913&sr=8-2&keywords=propane+pr essure+tester


Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: [GMCnet] 2 furnaces in one day [message #269659 is a reply to message #269443] Wed, 14 January 2015 12:04 Go to previous messageGo to next message
Ek_Lektro is currently offline  Ek_Lektro   United States
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Registered: March 2011
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Senior Member
Strange update to report on the 2 GMCs with their flaky furnaces.
First of all, yes, both had good strong 13.0+ volts (floating on shore power),
and both had their shut-off valves wide open,
and both had been working fine just the night before.. before they BOTH refused to light up...
within an hour of each other (weird).
Both had visible sparks, a strong-running fan, and plenty of propane left in the tanks,
but both refused to light... after dozens of attempts.

> Perhaps low gas pressure? Just a guess, but a the outside temperature goes down, the gas pressure drops.

I had thought about this, and so I ordered the recommended manometer so i could check things out; Hasn't arrived yet

http://www.amazon.com/General-Tools-Instruments-GPK035-Pressure/dp/B001TOFRNG/ref=sr_1_2?ie=UTF8&qid=1421160913&sr=8-2&keywords=propane+pr essure+tester

and I started looking through the online troubleshooting guides, thanks to everybody's postings..

So then yesterday, with no changes other than putting a different fresh 5 gallon propane bottle into the system (for the Eleganza and its DuoTherm)...BOTH furnaces lit up on the first attempt!
(The Birchhaven / Suburban still had its same 5 gallon bottle)

The only other thing that changed was the weather.... atmospheric conditions... Instead of 48 degrees, high humidity and intermittent light rain; it was now 60 degrees and dry (not really needing the heat, ha!)
So... Is it possible that "humidity" or lower barometric pressure could render a borderline flaky furnace inoperable? Could there be a work-around for such a thing, in a pinch? hold a hair dryer on the igniter or something? We've got so many other major projects in progress with the Birchhaven rebuild right now, that i might have to put off a total troubleshoot / disassembly / fix, for the moment. But of course i'll be taking notes for the next time :) ((Not sure how much heat we'll need in Mazatlan))

thanks again for all your shared info, everybody!
Greg / SolarSonic / Los Angeles
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Re: [GMCnet] 2 furnaces in one day [message #269660 is a reply to message #269443] Wed, 14 January 2015 12:35 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Registered: May 2010
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CRUD, I HIT THE wrong key. What I wanted to finish with was that
refrigerators and propane water heaters behave the same way when they are
inactive for a while. Sometimes a gentle tap on the gas valve will change
the symptoms, and if that happens in your case, remove the gas valve in the
furnace and check the inlet screen. If there is any foreign matter in
there, it needs to be removed.
Jim Hupy
Salem, OR
78 GMC Royale 403

On Wed, Jan 14, 2015 at 10:30 AM, James Hupy wrote:

> This is my take on your problem. I do not feel that you have a problem
> with either furnace mechanically or electrically. What I suspect is that
> the gas valves on each of the furnaces are not allowing gas to pass through
> them. You are so near a demand type regulator, (11 inches of water column
> is a bit over 1 psi.) that if there is anything like lint or dust or spider
> webs or insect remains present in them, they will balk and not allow
> propane to flow. The double regulator type seem to be more likely to act
> like this. Now with our 80% fill (OPD devices) the problem seems to be more
> prevalent, PARTICULARLY WITH INTERMITTENT USE OF THE FURNACES.
>
> On Wed, Jan 14, 2015 at 10:04 AM, Ek_Lektro wrote:
>
>> Strange update to report on the 2 GMCs with their flaky furnaces.
>> First of all, yes, both had good strong 13.0+ volts (floating on shore
>> power),
>> and both had their shut-off valves wide open,
>> and both had been working fine just the night before.. before they BOTH
>> refused to light up...
>> within an hour of each other (weird).
>> Both had visible sparks, a strong-running fan, and plenty of propane left
>> in the tanks,
>> but both refused to light... after dozens of attempts.
>>
>>> Perhaps low gas pressure? Just a guess, but a the outside temperature
>> goes down, the gas pressure drops.
>>
>> I had thought about this, and so I ordered the recommended manometer so i
>> could check things out; Hasn't arrived yet
>>
>>
>> http://www.amazon.com/General-Tools-Instruments-GPK035-Pressure/dp/B001TOFRNG/ref=sr_1_2?ie=UTF8&qid=1421160913&sr=8-2&keywords=propane+pr essure+tester
>>
>> and I started looking through the online troubleshooting guides, thanks
>> to everybody's postings..
>>
>> So then yesterday, with no changes other than putting a different fresh 5
>> gallon propane bottle into the system (for the Eleganza and its
>> DuoTherm)...BOTH furnaces lit up on the first attempt!
>> (The Birchhaven / Suburban still had its same 5 gallon bottle)
>>
>> The only other thing that changed was the weather.... atmospheric
>> conditions... Instead of 48 degrees, high humidity and intermittent light
>> rain; it was now 60 degrees and dry (not really needing the heat, ha!)
>> So... Is it possible that "humidity" or lower barometric pressure could
>> render a borderline flaky furnace inoperable? Could there be a work-around
>> for such a thing, in a pinch? hold a hair dryer on the igniter or
>> something? We've got so many other major projects in progress with the
>> Birchhaven rebuild right now, that i might have to put off a total
>> troubleshoot / disassembly / fix, for the moment. But of course i'll be
>> taking notes for the next time :) ((Not sure how much heat we'll need in
>> Mazatlan))
>>
>> thanks again for all your shared info, everybody!
>> Greg / SolarSonic / Los Angeles
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>>
>
>
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Re: [GMCnet] 2 furnaces in one day [message #269661 is a reply to message #269659] Wed, 14 January 2015 12:30 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
This is my take on your problem. I do not feel that you have a problem with
either furnace mechanically or electrically. What I suspect is that the gas
valves on each of the furnaces are not allowing gas to pass through them.
You are so near a demand type regulator, (11 inches of water column is a
bit over 1 psi.) that if there is anything like lint or dust or spider webs
or insect remains present in them, they will balk and not allow propane to
flow. The double regulator type seem to be more likely to act like this.
Now with our 80% fill (OPD devices) the problem seems to be more prevalent,
PARTICULARLY WITH INTERMITTENT USE OF THE FURNACES.

On Wed, Jan 14, 2015 at 10:04 AM, Ek_Lektro wrote:

> Strange update to report on the 2 GMCs with their flaky furnaces.
> First of all, yes, both had good strong 13.0+ volts (floating on shore
> power),
> and both had their shut-off valves wide open,
> and both had been working fine just the night before.. before they BOTH
> refused to light up...
> within an hour of each other (weird).
> Both had visible sparks, a strong-running fan, and plenty of propane left
> in the tanks,
> but both refused to light... after dozens of attempts.
>
>> Perhaps low gas pressure? Just a guess, but a the outside temperature
> goes down, the gas pressure drops.
>
> I had thought about this, and so I ordered the recommended manometer so i
> could check things out; Hasn't arrived yet
>
>
> http://www.amazon.com/General-Tools-Instruments-GPK035-Pressure/dp/B001TOFRNG/ref=sr_1_2?ie=UTF8&qid=1421160913&sr=8-2&keywords=propane+pr essure+tester
>
> and I started looking through the online troubleshooting guides, thanks to
> everybody's postings..
>
> So then yesterday, with no changes other than putting a different fresh 5
> gallon propane bottle into the system (for the Eleganza and its
> DuoTherm)...BOTH furnaces lit up on the first attempt!
> (The Birchhaven / Suburban still had its same 5 gallon bottle)
>
> The only other thing that changed was the weather.... atmospheric
> conditions... Instead of 48 degrees, high humidity and intermittent light
> rain; it was now 60 degrees and dry (not really needing the heat, ha!)
> So... Is it possible that "humidity" or lower barometric pressure could
> render a borderline flaky furnace inoperable? Could there be a work-around
> for such a thing, in a pinch? hold a hair dryer on the igniter or
> something? We've got so many other major projects in progress with the
> Birchhaven rebuild right now, that i might have to put off a total
> troubleshoot / disassembly / fix, for the moment. But of course i'll be
> taking notes for the next time :) ((Not sure how much heat we'll need in
> Mazatlan))
>
> thanks again for all your shared info, everybody!
> Greg / SolarSonic / Los Angeles
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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Re: [GMCnet] 2 furnaces in one day [message #269669 is a reply to message #269661] Wed, 14 January 2015 14:17 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
James Hupy wrote on Wed, 14 January 2015 13:30
This is my take on your problem. I do not feel that you have a problem with either furnace mechanically or electrically. What I suspect is that the gas valves on each of the furnaces are not allowing gas to pass through them. You are so near a demand type regulator, (11 inches of water column is a bit over 1 psi.) that if there is anything like lint or dust or spider webs or insect remains present in them, they will balk and not allow propane to flow. The double regulator type seem to be more likely to act like this. Now with our 80% fill (OPD devices) the problem seems to be more prevalent, PARTICULARLY WITH INTERMITTENT USE OF THE FURNACES.

Jim,

You missed on the conversion....
11 inches of water column (this is correct) is less than 1/2 of a PSI.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: [GMCnet] 2 furnaces in one day [message #269671 is a reply to message #269669] Wed, 14 January 2015 14:46 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Thanks Matt. What I was really trying to get across is the fact that there
is very, very little pressure there. I did not reference the chart, my bad.
I am in the shop working on an engine swap, tried to rely on my astute
powers of recall. Apparently they need recalibration. (Grin)
Jim Hupy
Salem, Or
78 GMC ROYALE 403
On Jan 14, 2015 12:17 PM, "Matt Colie" wrote:

> James Hupy wrote on Wed, 14 January 2015 13:30
>> This is my take on your problem. I do not feel that you have a problem
> with either furnace mechanically or electrically. What I suspect is that
>> the gas valves on each of the furnaces are not allowing gas to pass
> through them. You are so near a demand type regulator, (11 inches of water
>> column is a bit over 1 psi.) that if there is anything like lint or dust
> or spider webs or insect remains present in them, they will balk and not
>> allow propane to flow. The double regulator type seem to be more likely
> to act like this. Now with our 80% fill (OPD devices) the problem seems to
>> be more prevalent, PARTICULARLY WITH INTERMITTENT USE OF THE FURNACES.
>
> Jim,
>
> You missed on the conversion....
> 11 inches of water column (this is correct) is less than 1/2 of a PSI.
>
> Matt
> --
> Matt & Mary Colie - Members GMCMI, GMCES
> '73 Glacier 23 - Still Loving OE Rear Drum Brake with Applied Control Arms
> SE Michigan - Twixt A2 and Detroit
> _______________________________________________
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>
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Re: [GMCnet] 2 furnaces in one day [message #269704 is a reply to message #269443] Wed, 14 January 2015 20:28 Go to previous messageGo to next message
mild bill is currently offline  mild bill   Canada
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Registered: November 2014
Location: Edmonton, Alberta, Canada
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Just another thing to check. Don't know how clearly you saw the spark, whether it was seeing a flash of light or if you distinctly saw spark between the two electrodes. If you get a carbon track across the high tension electrode or spark plug so to speak or 40 year old spark plug wire from the coil to the plug there is a very good chance you are not getting all the voltage required to create a good spark to the ground electrode. I don't remember what my heater looked like because I trashed it however cars with bad wires won't start in those humid conditions and if you check at night under humid conditions you can see the spark jumping from the high tension wire to ground unless the wire is touching a piece of grounded metal where it might be difficult to witness. You can buy wire and boots cheap, imagine solid core or real wire as a conductor.

[Updated on: Wed, 14 January 2015 20:32]

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Re: [GMCnet] 2 furnaces in one day [message #269742 is a reply to message #269443] Thu, 15 January 2015 13:07 Go to previous messageGo to next message
Ek_Lektro is currently offline  Ek_Lektro   United States
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Registered: March 2011
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> Sometimes a gentle tap on the gas valve will change
> the symptoms, and if that happens in your case, remove the gas valve in the
> furnace and check the inlet screen. If there is any foreign matter in
> there, it needs to be removed.

Sounds like a good next step Jim, thanks.
But in case it does NOT misbehave again in a hurry (and give me the opportunity for the tapping test),
I'm wondering if there's any harm in just blowing some air in there, from the compressor?
I could either disconnect at the furnace itself, and blow through the gas valve...
or backwards from the gas valve towards the furnace gas inlet line.
But right now both furnaces are working without issue... (Until we really need em again, i'm sure :)
OK, Thanks much
Greg

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Re: [GMCnet] 2 furnaces in one day [message #269743 is a reply to message #269742] Thu, 15 January 2015 13:14 Go to previous message
James Hupy is currently offline  James Hupy   United States
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Registered: May 2010
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Be very careful using an air hose near those gas valves. They are designed
for a very slight amount of pressure, definitely not what comes out of shop
air hose, even with an OSHA approved nozzle, which we all use I am sure.
(VBG) I would use a Q-tip and MEK or Alcohol Solvent to clean those inlet
screens if you remove the lines. Gentle is the word here.
Jim Hupy
Salem, OR
78 GMC Royale 403

On Thu, Jan 15, 2015 at 11:07 AM, Ek_Lektro wrote:

>
>> Sometimes a gentle tap on the gas valve will change
>> the symptoms, and if that happens in your case, remove the gas valve in
> the
>> furnace and check the inlet screen. If there is any foreign matter in
>> there, it needs to be removed.
>
> Sounds like a good next step Jim, thanks.
> But in case it does NOT misbehave again in a hurry (and give me the
> opportunity for the tapping test),
> I'm wondering if there's any harm in just blowing some air in there, from
> the compressor?
> I could either disconnect at the furnace itself, and blow through the gas
> valve...
> or backwards from the gas valve towards the furnace gas inlet line.
> But right now both furnaces are working without issue... (Until we really
> need em again, i'm sure :)
> OK, Thanks much
> Greg
>
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> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
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