Help needed: Spark module problem on Dunkirk steam boiler, stops working every few days!

jjinnj

First the specifics, then the problem. Any feedback would be greatly appreciated. It's still pretty chilly in NJ; heat still needed.
Dunkirk series PSB-5D
Model #61CSB150---101--
Installed December 1992 by previous homeowner
Spark module: Honeywell S8610U Continuous Retry installed March 13, 2015, then another on March 18, 2015

PROBLEM (and I'm assuming too many details are better than not enough):

Less than two weeks ago, no heat. I had noticed in passing recently that the boiler would be sparking for longer than usual sometimes before starting up, so I suspected it was something electrical. I was able to get it going again by flipping the emergency shut-off switch off then on again. (But oddly, only the switch on the way down to the basement helped; the one on the boiler itself did not.)

I have a service contract with PSE&G, and they came out, but couldn't diagnose the problem because the heat was still working when repairman arrived. He assumed it must be the spark module, so installed a new one, but couldn't get the boiler going without tripping electrical wires. He then checked my thermostat and determined that was shot, installed a new one, then everything seemed to be working.

Four days later, it stopped again. LED flash code on module indicated "flame sensed out of sequence." Another PSE&G repairman came, and couldn't really figure it out. He saw the pilot light was on, but wasn't starting up the boiler. He spent time making calls to determine if the spark module was the correct one for the boiler, but no one could get an answer. Only thing he could come up with was it was a lemon, so he installed a new one, and I believe replaced the pilot assembly as well. Worth noting is he noticed that on the new spark module, there was not a cap for the plug for the damper (sorry, I don't remember the whole name of the part) like older models do, and my damper is hard-wired into the boiler, so he mused that could be part of the issue.

Now a week later, I'm back to no heat and the LED flash code indicating "flame sensed out of sequence." Does anyone have any ideas for this problem and how to fix it once and for all? I am desperate! I live in a 1928 colonial; it gets cold in the house pretty fast. Thanks in advance.

Spence

Do you have one wire or two coming from your pilot assembly? In other words, one or two "rods" in the pilot flame?

Do you know where the sequencing dip switches were set (little red block above the right mounting screw), or can you look?

jjinnj

This is where it becomes clear just how much of a laywoman I am:
There are three wires of different colors coming from different places. Photo attached. The pilot is lit right now by the way, even though no heat.
I cannot find the sequencing dip switches, but I will keep looking. I'm not finding a little red block, though I'm not entirely sure what item's mounting screw I'm looking for either!

jjinnj

Not sure if this is what you meant about sequencing dip switches (photo attached). The block is yellow, not red, there's nothing I can switch with my hands, and I can't really tell what the settings are anyway, but it seems like it has something to do with the pilot.

JStar

Sounds like the ignitor is grounding out causing a false flame signal. Or the pilot solenoid on the Gas Control Valve is stuck open. Where does that yellow wire go where it's off screen to the right?

jjinnj

The yellow wire goes into the PV slot in the ignitor.

I called a repairman in today (not PSE&G this time), and his diagnosis is that the ignitor is the wrong model. He thinks I need the Honeywell S8600M (which has been discontinued) because it does not have a slot for the damper (my damper is hard-wired into the boiler as stated above). But the S8610U, which is what PSE&G installed twice, does seem to be Honeywell's replacement for the 8600M, even though it does have a slot for the damper.

It looks like I can get a refurbished 8600M on eBay; the repairman today said he recommends switching to a standing pilot, but I don't know how I feel about that. For now, he got the heat going again, and showed me how to get it on myself if it goes off again by unplugging then plugging in the spark wire.

Abracadabra

Honeywell S8610 is the replacement for the s8600m as long as the dip switches are set properly. There's a table in the install manual that details how to set the dip switches based on what model you are trying to replace. The s8610 should have a jumper in the damper connector if you are not using it to control a damper. Once it's been used jumpered, you can't control a damper with it. I have found that Intermittent pilot issues like this are due to either poor grounding or a dirty ignition/sense rod (assuming a good ignition control). In your case the rod that provides the ignition is also sensing the presence of the pilot flame. Can you please provide a picture of the new ignition module installed showing what wires are connected?

Edited: Don't need a jumper for the s8610 if it's fresh never been used with a damper.

jjinnj

My bad. The yellow wire is in the ground slot (photos attached).
The PSE&G repairman did not leave me the install manual for the S8610, but I'm guessing I can find it online. Is the white cube with the holes in it (most visible in photo above) the jumper you are referring to?

jjinnj

Forgot to mention: I don't know for certain what igniter model was originally on my boiler, since the first repairman didn't leave that behind either.

Abracadabra

If the pilot lights, and the module flashes "out of sequence" the gas valve needs to be checked. The tech should also be able to check for pilot flame current.

jjinnj

Thank you. I know for sure the pilot was lit this morning and the module was flashing "out of sequence," and that was the case last week as well. The next time I call someone in, I will ask them to check those things.

don_9

Replace your ignition wire, the gray one n your trouble will go away.

Steamhead

Guys, I've run into this problem. I'm almost certain it's the gas valve not cutting off the pilot at the end of the cycle. Here is a simple check to perform:

Next time the boiler malfunctions, turn off the power to the boiler. The pilot should not be lit at this time. If it is, turn off the manual gas valve in the gas line feeding the boiler. If the pilot is still lit it will go out. Then turn the power back on to reset the spark module, turn the gas back on and try it again.

If the boiler starts normally, replace the gas valve. The above test will have shown that even with a complete absence of power, the pilot valve did not close.

The S8610U is a universal replacement module which is designed to replace a wide variety of Honeywell and competitive modules. In this case the old module was probably OK, but I'd leave the new one on because of its flash-code diagnostic feature.

jjinnj

Thank you for all the input everyone. I'm guessing it will stop working again when I need it most---like Saturday when it's supposed to be in the 20s and 30s---and then hopefully this will get resolved once and for all. And Steamhead, I was thinking the same thing about the new module being better because of the diagnostic feature.
I will post again once I have a resolution.