I have a older mobile home with the furnace in back accessed by a removable panel .It has worked great for the last three years and worked fine all winter . We live in Reno , NV . Two days ago we hade a bad wind storm (50 mph and up ) and it blew out my pilot light . Now it won't relight . I changed out the thermo coupler but no good . It is an Armstrong built in the 70,s . any advice or help would be greatly needed . We are retired and can't spend a lot of money . Thank You, Jim .
furnace pilot light
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Are you following the instructions? Does it light and then go out or never light?
Try holding the pilot valve button down 30 seconds to purge the line of air, let the gas clear from around the burner - try again.
Try holding the pilot valve button down 30 seconds to purge the line of air, let the gas clear from around the burner - try again.
I did all that . When I depress pilot button and light I get good flame , all blue no yellow but as soon as I start to release flam goes out . Also did a continuity and voltage check on both the old and new thermocouple , both are working so I reinstalled the old one in case the new one just wasn't a good match . I held the button for well over a minute till the thermos was cherry red . still no luck . Jim .
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Voltage from the thermocouple good after it warms up? don't know what the voltage should be since haven't come across that issue - but will be very low.
if the holding coil is getting voltage but it's not staying open, i would jump to the valve. Can't recommend changing it yourself; after it's changed gas pressure and monoxide should be checked.
if the holding coil is getting voltage but it's not staying open, i would jump to the valve. Can't recommend changing it yourself; after it's changed gas pressure and monoxide should be checked.
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If your thermocouple is turning cherry red both the old one and the new one and the pilot lights but goes out when you let go of the button I would suspect a bad gas valve. If it's the furnace I think it is it has a metal door over the gas valve? That's a very easy gas valve to change. Instead of trying to get a gas valve to match the model number of the furnace I would try to get a gas valve by matching the model number of the gas valve itself. Might save you a few dollars that way. That burner is pretty old make sure that none of it has rusted away before you spend money on a gas valve. I would tell you to check the heat exchanger also but I don't think you can see any of it on that furnace. If the wind blew out the flame make sure your cap is in good shape on the roof also. Be safe
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when the pilot went off the safety did its job and shut off the gas. Now you can't get the safety to open back up. That's why the valve is bad (I suspect). That is generally when a valve will fail in my opinion.JimL64 said:
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moving parts can fail especially if they're old and in one position for a very long time.
Do you know how if a water shutoff valve which is normally open starts leaking at the stem once you mess with it? same idea.
A 1970s furnace is one that I would be afraid to touch unless really needed without extra parts and the know how - ie being a licensed tech. Take things apart, fiddle with gas valves and if something breaks you get the blame, especially if whoever you're with or doing it for isn't very understanding of such things/has no confidence in your abilities. :devil3:
The gas valve is dangerous to change if you don't know what you're doing, have experience with gas lines. Also, the valve may come calibrated for a certain pressure and may need adjustment to get the firing/fuel input rate correct.
Do you know how if a water shutoff valve which is normally open starts leaking at the stem once you mess with it? same idea.
A 1970s furnace is one that I would be afraid to touch unless really needed without extra parts and the know how - ie being a licensed tech. Take things apart, fiddle with gas valves and if something breaks you get the blame, especially if whoever you're with or doing it for isn't very understanding of such things/has no confidence in your abilities. :devil3:
The gas valve is dangerous to change if you don't know what you're doing, have experience with gas lines. Also, the valve may come calibrated for a certain pressure and may need adjustment to get the firing/fuel input rate correct.
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Honestly, a 1970s furnace should only be repaired if there's no money to fix it or it's rarely used.
Long term in a climate which experiences real winters a new condensing furnace would slash the gas bills by 1/3rd, be infinitely safer.
Long term in a climate which experiences real winters a new condensing furnace would slash the gas bills by 1/3rd, be infinitely safer.
This answer makes some gas fitters nervous but I've freed up many older pilot electromagnets that would not otherwise re-engage by...
..repeating the pilot igniting sequence again and when that thermocouple is cherry red again and while you are still holding down the gas valve control... rap the metal side of the gas valve closest to the pilot tube with the plastic handle of a screwdriver a couple of times. Don't hit any plastic on that valve or the pilot tube itself.
Often the shock, in conjunction with the pulling coil, is enough to get the pilot solenoid to free itself again.
If the pilot doesn't stay on after trying this...you probably have an internal electrical fault in the coil and you should a get pro out to replace that valve.
Ask him if he can visually scope out the exchanger first to see if this repair is worthwhile or not. Unfortunately, the testing out the integrity of an exchanger often requires a working gas valve in order to do a CO plenum test or a O2 vent gas change with the fan coming on.
..repeating the pilot igniting sequence again and when that thermocouple is cherry red again and while you are still holding down the gas valve control... rap the metal side of the gas valve closest to the pilot tube with the plastic handle of a screwdriver a couple of times. Don't hit any plastic on that valve or the pilot tube itself.
Often the shock, in conjunction with the pulling coil, is enough to get the pilot solenoid to free itself again.
If the pilot doesn't stay on after trying this...you probably have an internal electrical fault in the coil and you should a get pro out to replace that valve.
Ask him if he can visually scope out the exchanger first to see if this repair is worthwhile or not. Unfortunately, the testing out the integrity of an exchanger often requires a working gas valve in order to do a CO plenum test or a O2 vent gas change with the fan coming on.
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Hopefully it's still safe and can be repaired - ie heat exchanger not cracked, burners not corroded.
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I do encourage you to see in advance if there are any low income weatherization programs in your area which may offer financial assistance or even cover furnace replacement should it ever be needed. Good to know what's out there so there's no emergency.
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