Wayne M-SRH Oil Burner Not Firing

It’s used to heat my garage, so there is no ductwork and it has a straight vent to the roof.

Stopped a few weeks ago. Pulled the gun assembly and the electrodes were blunted and black.

Replaced the electrodes and nozzle and set the proper gaps/spacing. Noticed that the burner/pump coupling had a crack in it but still put it back together again it ran fine for at least a day or two.

When I noticed it wasn’t running again, I flipped opened the transformer to find that the coupling had broken completely leaving only the coupling caps connected.

Pulled the whole assembly again to check gaps and to see if the electrodes were fouling. Everything was in order. Replaced the coupling and put everything back in its place.

When bleeding air from the system, the oil pump was drawing oil and the burner motor was turning. Automatic shutoff caused it to stop while bleeding. Hit the reset button a second time to try to complete the bleeding procedure and it shut down again.

I know I shouldn’t hit the reset button again since it’ll just inject more oil into the system so I’m trying to figure out what could be causing it not to fire.
Cad cell lens appears to be clean and clear. “Screwdriver test” on transformer gave me about a max 1” arc between the 2 transformer contacts. Nozzle and electrodes are new and set properly. Fuel hasn’t been added and the tank has at least 100 gallons in it.

I think the issue has to be 1) the flame detector (Robertshaw) isn’t working properly 2) the primary control isn’t working properly 3) the transformer (Webster 313-28AB91) isn’t providing enough spark

I don’t have a multimeter that will allow me to test 10000 volts but obviously it’s getting power to the transformer I just can’t tell if it’s enough. I’ve read that the arc should be closer to 2” due to the higher flash point of heating oil.
I’m thinking that if the transformer is failing slowly, then the new electrodes may have been enough to light the fuel even with a reduced output. Now it may be too low to light it at all. When it’s trying to fire, I can hear a slight change in the sound of the burner that may be the electrodes trying to light the fuel. After 30 seconds or so, it shuts down.

Not sure how to test the flame detector or how to tell if the primary control is doing what it’s supposed to do.

I haven’t put a lot of money into the repair so far but for a garage heater, I don’t want to buy more than I need to fix it.

Anyone have any experience with a Wayne M-SRH burner that can provide any suggestions? We were down to -18 outside this morning so I’d like to get it running again.

 

If your burner shut down while you bleeding it it's because there was no fire and with a 45 sec control that's normal.
Hit the reset and continue. If it goes off again, reset it again until it's bled.

As long as you have the bleeder open no oil is going into the chamber and your safe.
There's no need to check the cad cell or transformer because there's no oil getting to the nozzle until you close the bleeder.

You can't test transformers with a multimeter. They have special tester for that.
Cad cell doesn't come into play until it lights. Then if you know it's lit and it shuts down that's the time to check that.

Good Luck,

 

A common problem with Wayne burners is the way the electrodes are held in place. It is very easy to crack the porcelain under the set screw. I suggest you pull the electrodes again, clean them well, & inspect carefully. You may find a crack in the porcelain where they are mounted in the holder.

If all is well there, reinstall with these settings: 3/8" (+/- 1/16) above nozzle center, 5/32" gap, & 1/16" in front of the nozzle face.

Sometimes a pump will pump oil out the bleeder but not build pressure. Disconnect the small copper line going to the nozzle assembly & redirect it into a recepticle to catch the oil. Start the burner & see if you get a strong, solid stream of oil.

 

Thank you for the advice spott and Grady. The electrodes are in good shape but I will try to pull the copper line tomorrow when it's warmer (it's -15 right now).
An update on this issue:
The first time I pulled the gun assembly, I used a ruler to set the electrodes. The second time, when I put the new coupling in, I pulled the gun assembly and reset them using one of the blue plastic spacers. I pulled it again tonight and set with a ruler again. I cleaned the cad cell lens just in case. When I bled the system, I had a lot of air in the line. I ran about a gallon through and still had almost foamy oil from the bubbles. I closed the bleeder valve while the pump was still running and it fired. Flames looked decent through the inspection port but then it shut down again. It won't fire unless I bleed it and then close the valve before the auto-shutoff occurs. With my limited experience with oil burners I can think of 3 possibilities:
1. When the pump is running oil to the bleeder and I close the valve quickly, the flow of oil is sufficient to shoot enough into the combustion chamber to fire it. Not sure if that's possible but it sounds somewhat logical to me.
2. The cad cell isn't working properly
3. The cold (currently -15 F) may have started to gel the fuel? The line into the pump in the garage has frost on the outside and the tank is outside and above ground. Maybe I've fixed the issues but the fuel isn't getting into the system well enough to keep it burning and it just sat for a couple of days. Maybe that's why there is so much air in the lines?

 

I think you have a fuel gelling issue. Dump a few gallons of K1 in the tank and stir it up. That will keep it flowing.

 

Thank you, that's what I was hoping. K1 is just kerosene from the gas station, right?
I just realized that I failed to mention that my filter is outside. Doing a little research has taught me that I should take the media out of the outside filter and move the filter inside. It's still below freezing inside but once it thaws (and if it will then run properly) it should keep flowing.

 

If you have a two pipe fuel system & from the sound of things you probably don't, abandon the return line & install a Tigerloop.

Moving the filter inside would be a good move. In order to change the gel point of the fuel significantly, you will have to add at least 20% kerosene. I suggest an anti-gelling fuel treatment available at many hardware stores & nearly any plumbing supply house. There are many brands but a few which come to mind are: HOT, Hot Shot, Fuel Flo(w?), & STR-2.

BTW: Take that piece of blue plastic crap & throw it as far as you can, grind it into little pieces, crush it, melt it to a puddle, or otherwise dispose of it for it is JUNK.

 

Yeah, the blue plastic gauge doesn't get me close to the right measurements.

When I open the bleeder valve the oil is bubbly almost to the point of being foamy. If I close the bleeder before the auto shutdown it fires and stays lit for 15 seconds or so then it goes out and the cad cell shuts it down.

Took Grady's advice and pulled the small copper line off the gun and started it again... no oil coming out of the line. The pump appears to be spinning just fine with the new coupling but no oil comes out except at the bleeder. I don't understand why oil would come out of the bleeder but not the copper line or why it only fires up when I close the bleeder but not if I start it with the valve closed.

Does it sound like a dirty pump strainer? A failed pump?

 

If you are getting foam or a lot of bubbles, you either have an air leak, a bad pump, or are pulling a very high vacuum. The vacuum is easy to check with a gauge. If you are pulling more than 8-10 inches you have some sort of restriction, possibly due to the cold oil. If you have not done so, it certainly can't hurt to check the pump strainer. Repace if there is anything on it.

 

You seem pretty handy. What about putting some oil or kerosene into a 5 gal container, removing the oil line from the pump that's connected to the tank and run a piece of tubing from the container to the burner.
If it runs without problems then you its the oil in the tank and act accordingly.
Until you move the filter inside you can remove the cartridge. It will freeze unless you put in a box with some heat, even a light bulb will keep it flowing.

You will have to flair the tubing to go on the pump if that's what you have.

 

I had a container of oil that I had bled from the valve so I disconnected the line to the tank and ran a hose into the container. It didn't seem to be pulling through very well so I disconnected the small copper line from the pump to the gun assembly and ran another clear tube back into the same container. I wasn't getting anything through.
I though maybe I could open the pump and clean/replace the strainer and gasket so I took the pump off. After removing the 4 bolts that hold the cover on, the thing seems to be permanently sealed. I tapped on it with a hammer to try to separate the pieces. I thought about trying to pry it with a screwdriver but I figured I'd probably damage it so that it wouldn't seal again. I used an air compressor to blow out both the inlet and outlet and put it back on. It had, and still does, move freely and turns when the motor and coupling turn.
I bled the system again (still fairly bubbly but seems to be less so than before) and fired it up. I held the door switch and waited for it to shut down... and it ran until the blower came on to distribute the hot air! I closed the door and it burned for at least 3 or 4 minutes before it stopped. I bled it again and closed the door and it did the same thing again before stopping. Had to call it quits for the night so I unplugged it.
It seems to be moving enough oil to run longer now but won't fire without me bleeding it and closing the valve while it's still running. It may be that the oil was just too cold. It's supposed to hit the low 40s tomorrow so that should tell the tale.

 

New member, but have been using forum for a week or so with my own problem, So wanna give props and a big thumbs up held high to the moderators. you guys sincerely do a great job explaining stuff so thank You. try putting pipe dope on threads of fittings before and after oil filter cup learned dat da hard way. and for anyone else out their you can bleed a 2pipe system. It should and will bleed itself, but not if You have an air leak. Nothin prettier than that clear red stream. Good luck

 

A,
It looks like you may have a suntec oil pump on there.
If that's the case it will come apart at the seem. Pry apart with your screwdriver and hammer. You will not damage it and there is a filter screen in there. If its that hard to take apart its probably plugged with crap.
It will look like grease when you open it.

They can be cleaned or replaced but you will need a new pump gasket that usually comes with the screen and they're very inexpensive.
Make sure you clean the other gasket off real good or you could have an air leak.

Good Luck,

 

A rubber or plastic hammer with a firm rap or three to the corner of the strainer cover will get the job done in most cases. A good sized screwdriver inserted between the intake boss & the pressure adjustment hex may be needed on really stuck covers.

As Spott said, get all of the old gasket off both the cover & body before installing the new gasket & strainer.

 

It's working! Thanks everyone for the help and advice. I blew out the whole line with a compressor, gapped the electrodes again, and put TFE paste on every connection up to the gun assembly. The first time I bled it, all of the air came out of the system. After a few starts and stops, it fires on its own and keeps running even when I let it cool down and then turn up the thermostat.
I already ordered a gasket and screen but I may just hold on to it until the summer. Might be best to just leave well enough alone.
Thanks again all!

 

The next time you are working on it clean off all of that TFE paste. If you must use a pipe joint compound, use #2 Permatex. TFE & fuel oil don't play well together. The fuel will attack the TFE & you could end up with it in the pump & nozzle. I've seen it destroy more than one pump.

Flare fittings should never be doped with anything on the flare end & compression fittings should never be used.

 

I'm glad its working for you but it was still a good idea to get the screen. If the line had that much crap it had to go to the pump screen.
If he problem comes back you'll have it.

Stay warm,

 

The furncace calls for heat but does not fire. Primed oil, the motor kicks on but does not fire when it's supposed to, just shuts down. Get no spark from the old transformer and replaced it with new transformer today BUT still have no spark. Some one told me it could be the contoller that the thermostat wires go to??? I have the old school one with no LED's have to look up part number but someone said I could be replace with a newer one. But wanted to get some feedback from you folks. To see ifi"m heading in the right direction. he also told me to check for voltage when the motor kicks on and if there is no voltage then it's the contrller where he has seen more than one that one side of it can burn out??? Didn't perform that test but does this sound right?? Would appreciate any input you might have!

 

You say you are not getting any spark, even with a new ignition transformer. I would like you to remove the primary control (the box with the reset button) & tell me if there is a blue wire going to one side of the transformer. If there is, disconnect the transformer from the blue wire & connect it to the orange. Then try the burner again. Be sure to put a wire nut on the end of the blue wire.

 

Hi Grady, I will check that out. All is did was just hook the new transformer up to the wires the old one was hooked too which has a blue wire. I did see some instructions saying to do that with the replacement transformer which is an "Allanson", my old one is the original Franceformer. Hehehe maybe that is the issue! Hopefully it has an orange wire lol! If it doesn't, what would be the next move? Wire it back to the original blue wire the old transformer was wired to like I currently have it and look for another power issue? Thank you and I will let you know what I find in the next few days.

 

Just do as Grady described and go to orange wire which should have a motor lead to it. Also check your connections for the other of lead of the transformer.

 

It worked I owe yah one! Thank you for taking time out of your day to help me! It helped a good friend of mine stay warm who is going through some tough times right now.

 

The problem it seems, was with the blue wire not sending power to the transformer. Especially with older controls, that blue wire was a common problem.

 

Well it's been a day and no problems. So the blue wires blues have gone away guys lol! Thanks again!

 

Good to hear. Hope it continues as it's going.