GE atomizing oil boiler

jfrancis98

I need help a GE atomizing oil boiler, installed in 1965 in Salmon Idaho. I’ve been told there’s only 2 of these west of the Mississippi River. Any information will be greatly appreciated. I found a sales brochure from the 1960s, however I need technical information on how this works so I can get these nice folks through the last bit of winter.

EBEBRATT-Ed

I don't have any information on those. They were built like tanks and lasted forever. Parts are extinct.

I know Beckett conversion burners can be installed, maybe Carlin too. I wouldn't want to change the boilers they weigh a ton

jfrancis98

Thanks. I have to change it this summer. I’m tempted to open an oil boiler museum in their basement with this being the first piece.

Steamhead

Where to start..............

Basically, the motor-compressor unit pressurizes the oil and air, which are pre-mixed before being sprayed into the chamber. There is no high-pressure "nozzle" like we're used to. The duct coming off the m-c unit goes to the bottom of the unit where it provides a "cushion" of air for the flame. Combustion products exit thru holes in the top rear which open into a duct going down the rear and out the bottom.

The whole thing is controlled by the "Master Control" which was basically a motor-driven series of cams that operated in a sequence of steps according to input from the various controls and sensors. This is the control with the reset button on it.

We have one of these in our customer base but it has been retrofitted with a Beckett AFG. Yes, it's built like a tank and also has asbestos in it, so replacement would be quite involved.

Somewhere I have some old Sid Harvey stuff with service information on these things. I'll see if I can find it. Hopefully @ScottSecor will chime in- he's worked on these in NJ.

jfrancis98

Thank you!!!

HVACNUT

Is there spark? The ignition transformer looks like it has a tar pit.

jfrancis98

Yes. It locks out intermittently on the stack switch. I'm hoping there this weekend to check electrodes etc. The customer said it’s been 9 years since it’s been serviced and he also ran it out of oil 2 weeks ago. I’ve got a new oil filter and I’m bringing a stack switch even though I bet it may just need a cleaning. Anyone know about the electrodes?

jfrancis98

Going there this weekend. Maybe hoping......

Steamhead

As promised, @jfrancis98 - here's what I can find. The first part comes from the 1960 Audel Oil Burner Guide, written by Frank Graham. The second part is from the 1966 Sid Harvey Trouble Shooting Guide, and contains more of the specifics.

@Erin Holohan Haskell , feel free to add this to the Heating Museum.

jfrancis98

Thank you so much!!!

HVACNUT

@Steamhead , I've worked on a few with the Beckett conversion eons ago and I'll never need it, but I stole the download anyway. I love a good read. Thanks.

Was that the EK of its day?
Just a little different, more efficient animal than the rest?

ScottSecor

The large thing on the top with the brown canvas boot is called a compressor. The compressor provides two types of air, primary and secondary. Primary (compressed) air for combustion flows through the smaller copper tube that feeds the nozzle. Secondary air for combustion comes from the blower wheel that is just below the top of the compressor and delivers air through the canvas boot where the majority of the air is delivered to the base of the boiler, in addition some air flows through the flexible corrugated tube into the nozzle assembly to cool the assembly and provide additional air for combustion. The compressor also acts as a low-pressure oil pump. This pump pulls oil from the indoor or underground oil tank (with only one oil line, no return needed) and pressurizes the oil. The oil feeds the nozzle through the larger copper line. The oil pump is self-priming and is capable of bleeding itself in most cases. There are two electrical windings inside the compressor (part of the stator) one is the ‘start’ winding and the other is the ‘run’ winding.

The item in the center of the top of the boiler is the nozzle assembly. There are two copper tubes that provide primary air and oil to the nozzle, each is fitted with inverted flare fittings. The oil line is fitted with a 120-volt (open) solenoid that sits below the top of the boiler tray (just below the two 16-gauge black insulated wires). This oil solenoid is normally closed and only opens after the ignition transformer is energized and the compressor goes from the ‘start’ mode and goes into the ‘run’ mode. The oil solenoid is primitive but very effective. The solenoid consists of a simple needle and sheath wrapped with a coil. Whenever the coil is energized the needle lifts and allows oil to enter the nozzle. At the end of a cycle the needle drops and the flow of oil stops.

The master control in your photo is the second generation. They are “sealed” units and cannot be serviced. The master control serves many functions while acting as a timer. In a nutshell here is the schedule of operations. Upon call for heat (or dhw on many models) the master control ‘clock’ begins to rotate. If the flame detector (mounted on the front the boiler about waist high, to the left of the round front door) is in the ‘cold’ position the master control goes into the ‘start’ mode. Once in start mode, the start windings will be energized on the compressor and the oil will begin to flow from the tank, air will be blown into the bottom of the boiler, air will blow through the nozzle assembly and the internal clock will start. After a few seconds, the start windings will de-energize and the run windings will kick in. A few seconds later the 120-volt ignition transformer will get energized and simultaneously the 120-volt oil solenoid will get energized. You should be able to see the spark by lifting the chain on the lever mounted to the front door and looking upward at the center of the boiler. After three seconds you should see a flame ignite two to five inches below the end of the nozzle. The flame should be at least one foot long and ideally appear to bounce off the bottom of the boiler and come upward at least a few inches. After a few seconds the flame detector will sense the heat from the flame and ‘tell’ the master control to keep pumping air and oil into the boiler for as long as the flame is evident and there’s a call for heat/dhw. The ignition transformer should deenergize when the flame detector senses the heat and goes into run mode.

In your case you wrote; “It locks out intermittently on the stack switch.” I’m not sure what you mean by stack switch? There is a flue pressure switch at the back of the boiler where the smoke pipe connects to the boiler, but on most of the ones we serviced that was “jumped out.” There is a reset button that you may be referring to, this button acts like a modern reset button on a cad cell relay and cycles the master control if there is a flame failure.

Erin Holohan Haskell

Steamhead said:

As promised, @jfrancis98 - here's what I can find. The first part comes from the 1960 Audel Oil Burner Guide, written by Frank Graham. The second part is from the 1966 Sid Harvey Trouble Shooting Guide, and contains more of the specifics.

@Erin Holohan Haskell , feel free to add this to the Heating Museum.

Will do. Thanks!

jfrancis98

First off, thank you for the information!

The stack switch is in installed in the vent pipe, a bimetallic probe senses the flue gas and keeps the burner on if they are hot enough. I think this has a 75 second lockout.
Kind of primitive but it’s what I have to work with.

jfrancis98

THANKS to all who have contributed, I really appreciate the help.

ScottSecor

@jfrancis98 is it a GE brand stack switch or is a Honeywell that looks similar to this stack relay?
https://www.supplyhouse.com/Honeywell-RA117A1047-Protectorelay-Oil-Burner-Control-with-75-seconds-lock-out-timing

If it's the Honeywell type above, most likely it is not original to the boiler. I'm guessing the flame detector or at least part of the master control failed and someone was forced to get creative and installed a stack relay. I guess it worked out.

@jfrancis98 check your inbox

jfrancis98

Yes. It’s the RA1161-1055.
I’m guessing the gentlemen that used to work in it who passed away 9 years ago put this in.