Lochinvar WB80 not lighting, many new parts already. SOLVED
Comments
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About things getting fried as mattmia2 mentioned. The switch on the DC side of the bridge rectifier with no protection from the coil is poor engineering, the switch may suffer from excessive arcing. I would not use that switch much.
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
there is about $5-$10 of components on that board at retail prices. in production quantitiy it is probably well under $5
you can test the coils on the valve with an ohmmeter, you should see maybe tens to a few thousand ohms of resistance between each set of pins or possibly either pair of pins and the center pin. the datasheet is vague about the pinout of the gas valve
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Looking as this some more, this looks very awkward to do live electrical measurements on the rectifier board. If I worked on this situation often I would build an extender board or cable (a male / female extension cord) to get the rectifier board away from the Gas Valve.
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
I am wondering if I can impose upon one of you pros to contact the Lochinvar Tech Support at 800-722-2101 and ask about this rectifier plug. Boiler is Lochinvar-Knight WB080, serial number J09H10103093. We have not received any call backs from the local service people (maybe we shouldn't have paid our bill so quickly) and we would love to get this resolved.
In the Lochinvar Parts list for this range of boilers, there is no clear listing of the G/V harness. There is a listing for "WRE 20030 - Harness, Connection Board" which comes up for sale without any pictures but listing for $125 (about the price for the Honeywell 50015704-001 part number on our G/V harness which is not very available). Can the WRE 2205 G/V Harness (listed on similar boiler KB 80 parts list) work as a replacement? Maybe they did away with that on/off switch on the Honeywell part?
So, the question to Lochinvar Tech Support -
Is part # WRE20030 the G/V Rectifier Plug for the WB080? If not, what is the part number for that plug, and are they known to go bad and prevent G/V from functioning?
Will # WRE2205 from the KB 80 work as a replacement?
It's not really possible for me to try and resolder or replace just the bridge rectifier in our plug, would rather just purchase a new replacement. After all the money already thrown at this problem a bit more won't matter if it works! If I could get the "best tech" to come back out I would gladly have him perform the tests recommended!
I really appreciate the replies, efforts to analyze this fault, and the deep dive into the rectifier, but as you might expect we're just hoping to get heat.
Thank you!
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I suspect the "best tech" is just as frustrated as you are except he does not have to live with the situation on a day to day basis.
The 50015704-001 on eBay may be a good direction to go since you can change it yourself and it is the same part number. The molded version may be wired different inside, the only to tell is to get one and compare it electrically to the 50015704-001, probably not something you could do. If it is not compatible it could damage the control board, or simply do nothing.
Too bad you don't have anyone local that can do electronic circuit repair (even a hobbyist), there is not much there, the bridge rectifier is very inexpensive (if needed), the switched could be bypassed if defective. Intermittent bad solder joints can cause the behavior you are experiencing.
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
a little contact cleaner in that switch could possibly fix it too. that type of switch doesn't do well with low current signals and infrequent use.
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what part of Canada are you located in? Depending where, the factory rep may be helpful in finding an adequate tech.
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FWIW, I had a Triangle Tube boiler some years ago that had the gas valve rectifier fail. Not saying thats your problem but just saying it has happened before.
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Sunday morning update. Yesterday I took a good look at the rectifier circuit board under a magnifying work light. All the soldered joints look perfect, nice and clean, no cracks. I used a electronic components cleaning solution to clean the on/off switch and tested with my basic multimeter. It works.
That's about the extent of my knowledge of testing. I have no way of providing 24vac to see if rectifier is working correctly.
Let's say the rectifier plug to the G/V is working correctly, what else is there to check that hasn't been done? What else could be keeping the boiler from firing? It has spark - just doesn't seem to be getting gas? Once again, can the Air Pressure puck be defective without throwing a code? Is there a way to check it? If the Control Board is not receiving the right message that air is flowing would that prevent it from sending signal to G/V to open?
As a recap. G/V and burner were replaced by junior tech, boiler fired up and seemed to be running fine. DHW and SH both working. Then several hours later boiler quit ("No Flame Running"), hit reset, ("No Flame Ign") multiple retries ("No Flame Ign"). Called service provider, they sent out "best tech", he spent hours checking - still dead. Perhaps bad Control Board? New Control Board $$$. Still dead.
Among the ("No Flame Ign") codes did get one ("G/V Relay Fail"), looked up in troubleshooting guide, it said check G/V harness which lead me to rectifier plug and where we sit now. Service people have not returned our calls. This whole time we have been very polite and have paid our bills promptly.
The joys of living in a small mountain village.
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you can test the bridge rectifier this way using the diode check function of the meter you can figure out which terminals are which using the diagram above and the "+" "-" and "~" markings on the rectifier, with the board disconnected
diodes should be about .2-.7 v in one direction and infinity in the other. if they are close to 0 in both directions the rectifier is shorted.
the gas valve should have continuity between each pin here, test it with the ohmmeter on the meter. probably a few hundred to a few thousand ohms and they should both be in the same ballpark. none of this beyond looking for 24vac from the control really requires in circuit energized testing.
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Well if I was there I would carefully 'Back Probe' (Red Arrows, so the load of the gas valve is in the circuit) this connector the see if the the ignition process is even getting that far. 24 VAC should appear there during an ignition attempt.
To me it seems odd that you are no longer smelling gas at the vent. Which seems like the Gas Valve is not working, not being commanded (energized) to open or no gas supply.
Connector pin fitment of the connectors can be an issue too, verify the connectors are not damaged or deformed.
To me, at this point you have to figure out what part of the ignition process is actually missing. Draft (proper air flow), fuel, ignition (spark, where it actually needs to be), something is missing.
BTW diodes (the bridge rectifier) rarely fail open, they usually short when they fail. If shorted that could cause other damage to the control board or blow a fuse which is apparently not happening.
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
Monday update.
mattmia2 Thanks for the suggestions - I got online and learned how to test diodes with my MM. As far as I can tell the bridge rectifier is good with .584 at each corner and open in opposite. The gas valve was much harder to check because of access. After practicing with the original G/V on the bench I made up a couple leads with connectors and shrink tubing. Was still very difficult to attach to G/V in boiler. What I came up with was .033 on V1 and .017 on V2 on original G/V. The new G/V was .028 for V1 and .018 for V2 (meter set to 2K) These numbers for the gas valve in the boiler are a bit sketchy, it was very difficult to get good contact.
Also I played around with Air Pressure valve, it seems to be fine. Pulling a slight vacuum causes contact to close and leaving the tube off it threw a AP failure code. I wasn't able to do a manometer/multimeter check while calling for heat as the online videos suggest but the thing seems to be working.
109A_5 I will attempt to do the 24vac test at the connector today. All the wiring and connectors are in good condition.
Thanks once again for the help and suggestions!
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28 and 18 ohms seems right. the coils in the gas valve are probably good.
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109A_5 - Just to be sure I understand you correctly. You want me to insert the red and black multimeter probes into the back of the G/V harness connector at the gas valve and check for 24vac?
Space is tight so I was all set up with a mini harness made of a couple pieces of wire inserted into the back of connector and spades to hold the probes of my multimeter, dial set to V˜200, when I got cold feet. Want to be sure I'm not gonna short something (don't want to let the smoke out!) 😀.
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Did the ohmmeter measurements match the paring or grouping of the pins like in the image from the datasheet ?
If you like doing tests with the multimeter, here is another.
Again with the Diode Check function, plug the rectifier board into either Gas Valve maybe do both Gas Valves. Touch the probes to the two pin connector pins (switch On), you should see double the corner to corner voltage of the previous bridge rectifier test (0.584 x 2 = 1.168). Then reverse the probes to the pins, it should be the same.
This verifies the whole path through the bridge rectifier, switch, connectors, and at least one solenoid coil (hopefully both).
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
Yes basically you are poking the meter probes into the connector body on the same side the wires enter it.
You DO NOT want to jamb the probes in damaging anything, also you do not want to short out anything. The way I often do it is a thin bare wire will slide into the connector body slot where the pin lives (next to the pins) then I use an alligator clip lead to connect the thin wire(s) to the meter probe(s). If you have a helper you can hold the probes and have the helper turn the boiler on.
If you have other resources that will perform the same task that is fine too, just no damage and no short circuits to make the measurement.
I usually end up doing it alone so the set up is easy for me.
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
Another test I would do, and it is mostly informational, and ultimately may not have any diagnostic value. Since IMO the rectifier printed circuit board does not appear to match the V1 and V2 terminals in the datasheet for the solenoid coils wired in parallel. Parallel wired solenoid coils are probably expected but it may not be.
With the rectifier board connected to a gas valve and the switch On, I would measure the resistance (Ohmmeter mode) at the points illustrated in the image. It could be done on either side of the board which ever is easier.
From your previous resistance readings of V1 and V2, I would expect the readings in this case to be in the
46 to 50 Ohm range if the solenoid coils are wired in series
or about 11 Ohms if the solenoid coils are wired in parallel.
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
109A_5 One more time to make sure I get this right (sorry for dumb questions).
When testing 24vac at the connection to the G/V from the Control Board (yellow & red wires) you want me to touch the MM probes to both wires at the same time? Or from one wire and then to a ground source during ignition attempt? (I have a couple very thin wires inserted into back of connector and spades for MM probes)
Right now when I connect MM probes to both wires I get a reading of 1.168 like you predicted above (without boiler power or ignition attempt).
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Sorry I should have clarified this: ("Right now when I connect MM probes to both wires I get a reading of 1.168 like you predicted above") This is without turning on the boiler or ignition attempt.
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Yes, for example; the Red meter probe to the Red wire connector pin, Black meter probe to the Yellow wire connector pin. Each probe going to its own wire connector pin at the same time to measure the voltage. The goal here is to see if there is 24 VAC across those two wires at some point during the ignition process. Since the control board should send 24 VAC to the Gas Valve on those wires. The 24 VAC is then rectified by the rectifier board and the DC is applied to the solenoid coils of the Gas Valve.
No 24 VAC to the Gas Valve, it will never open and supply gas to the burner.
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
Did you swap the meter probe positions to test it in the other direction ?
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
I hooked up leads like you suggested. Set MM to 200V˜, turned on boiler and hit reset, got 6.3 during ignition attempt.
Now what?
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what's the output of the transformer when it attempts to ignite? should be about 24vac.
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It appears you are getting no (or very limited) power to the Gas Valve, so it is doing nothing. Just as a sanity check I would repeat the 24 VAC check during an ignition attempt at the other end of the Yellow and Red wires. Also I believe the 120 VAC to 24 VAC transformer is probably working, but verify it.
This is where many get lost. I have mapped out the path (in Green) that I believe is the Hot side of the 24 VAC that it must take to get to the Gas Valve during an ignition attempt and for it to run the burner. It looks like the Low side of the 24 VAC is referenced to a common ground (Green arrow), that may or may not be chassis ground. You may have to identify the low side of the transformer by using the mutimeter, and use that as the meter's reference point (like X5-1) for voltage measurments. I would expect it would be the side that does not have the 3.5 Amp fuse. EDIT: By the way, are the fuse and fuse holder in good shape ?
Many things in that path may set codes if all else is normal. So to me best practice with troubleshooting an issue like this (no power to the Gas Valve) is verify the 24 VAC source at the transformer first, then pick something easy in the middle of the path and test there, like maybe the Louver Proving switch pins or terminals 7 & 8 for example. Depending what you find there during ignition attempts determines which direction to go.
No power, head toward the power source.
Power good, head toward the load (the Gas Valve).
Also if pin or terminal 7 has power and 8 does not, does the Louver relay coil have power ?
Some things that are normally closed can be continuity or Ohmmeter checked, however I have found that powered up tests using the actual load (the Gas Valve in this case) is the best way, you just have to be more careful.
Since I believe the integrated control was replaced (now assumed good) I be very suspicious of whats left like wiring and safety limit controls and connections. It is a treasure hunt, be patient, take notes if needed.
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
Some things may just have jumpers if your system did not need that feature.
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
By the way, it would not surprise me with the way things have played out, with the intermittent operation and the brief restoration of operation after agitation, if there is a bad solder connection on the back side of this connection board. A lot of that path highlighted in Green above loops through that connection board.
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
Here is an example (from another members post) of a severely failed solder joint, often it is just a slight crack that need magnification to see easily. Some of the others solder joints in the picture don't look so good either. A common failure with this common aquastat.
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
109A_5 - Thank you for the additional info, I'll need to spend some time reading.
First an update. Last night (Tuesday) after I had got those disappointing numbers I spent some time poking around the cabinet trying to see what else it could be. The only wires I hadn't yet disconnected and redid were these to the top of the heat exchanger for the flue temp, and the two inlet/outlet temp sensors. Unplugged - replugged, wiggle the wires and hit Reset.
It fired up!
I let it run for a couple hours to heat the DHW and then watched it switch to SH. We've been using some portable space heaters to keep warm and outside temps have moderated so after it reached "Standby" and shut itself off I turned off the power. It was late at night/bedtime, I didn't want to take the time to run through the setup on the new control board (time/date/temp set-points,etc.) and wasn't sure what parameters might be pre-loaded on the board. Could it over-heat?
When I went to fire it up again today it failed. "No Flame Ign" Unplugged the sensors again, tried cleaning with the electric contact cleaner, wiggle wires, hit Reset. Fired up. OK good, but while I went to my laptop for the service manual it shut down. No go since.
All those wires look perfect, the connectors are clean, connection at board are good. Was it just a coincidence it fired up?
Like I said I'll study the info above. Again the board is new, the secondary board looks fine (I had already checked that a while ago) wires are all solid, connections are tight.
One thing I would note, during those couple times when it did fire up I heard a sort of fluttering sound coming from the Air Pressure Switch during ignition. Have never heard that sound during all failed ignition attempts. The puck (PRS20015) has a 2.50 wc (IIRC), I have no way to check that. All I did was gently suck on it to check if the contact closed. If I simply pulled the tube from the intake off the puck the unit threw a "APS Open" code. Any chance it could be sticking or something? The fact that it's not making any noise during failed ignition attempts seems significant?
Thank you very much for suggestions and help!
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The Air Pressure Switch (Orange box) may be an excellent observation. It is in the path that the 24 VAC has to pass through to get to the Gas Valve. However if the load side of the air pressure switch had no power (if the Air Pressure Switch is open) I would think the Integrated Control would detect that and create a unique code since it goes into the Integrated Control at X5-11. Maybe the lack of detection or error message priority was an engineering oversight.
Seems there is a error message for the Air Pressure Switch
With the meter you can test the voltage across the Air Pressure Switch (during an ignition attempt) with 24 VAC across the switch the switch is open, 0 VAC across the switch the switch is closed and passing the power through. Or if you know where the 24 VAC low or common is (maybe chassis ground or maybe X5-1) you can test one side than the other of the switch during a no fire ignition event.
I would think the factory defaults would be safe. But I suspect that Integrated Control may be used in multiple models so I would go through all the parameters to verify.
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
All this was inspected and/or verified ?
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
Yes, all the checks listed were done including the air intake pipe was cleaned (it was fine, very little debris), the exhaust side was cleaned and it's slope was changed by "best tech" to reduce age droop for better condensate drainage. I'll try the voltage check.
As you can imagine it's very frustrating, but getting it to light at all is encouraging.
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" All those wires look perfect, the connectors are clean, connection at board are good. Was it just a coincidence it fired up? "
Just to be clear, the back side of the Connection Board, where the solder joints are was closely inspected ?
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
Since it is intermittent but has long outages of no fire I would chase out the 24 VAC power path to the Gas Valve. That will probably determine a direction to what is causing the interruption in the 24 VAC power to the Gas Valve.
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
In the wiring diagram I was looking at some of the wire colors seemed to not match your pictures. So I looked at some older manual versions. Interestingly the jumper circled in Red and then in the Red box on the wiring diagram is in the circuit that supplies power to the Gas Valve, it was a Manual Reset High Limit in another version. And you were just moving things around up there, I would inspect that jumper closely and maybe take a voltage measurement at and just past that part of the circuit.
Also it appears the circuit common is bonded to chassis ground (Green boxes).
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System1 -
Saturday update. Once again thank you to 109A_5 for your help and time on this problem! I have to admit to being confused by the schematic, it seems a lot of those paths are on the circuit board and I'm reluctant to fool with a $1000 board.
HOWEVER, I'm getting intermittent firing again. I believe this is either low voltage due to several factors, or just plain electrical wiring faults. I'm wary of trying to trace any voltage on the control board itself, but I did replace a wire to the DHW tank temp sensor that was so tightly bound to the pipes the heat had melted the casing. However the wire was still good when I checked it with meter. I also pulled a couple connectors off and cleaned with contact cleaner. But, when I hit reset it fired! Ran for about 10 minutes and died.
As it tried to re-ignite I started juggling wires, starting with the connector at the top left that seemed to help the other night:
While I was jiggling this connector it started to fire and I heard a clicking sound coming from this device on the side of the heat exchanger:
Boiler fired as long as I held that top connector with pressure to one side, died when I left off - so, bad connector! But can you please tell me what that device is on the side and why it's clicking? Should I pull it out and inspect? Could it be dirty?
Can it also be I'm chasing a bunch of old connections that are accumulating in low voltage? That 4 pin connector on top (it's either inlet or outlet temp sender) is part of the whole cabinet harness which sells for about $400 (if I can find one) so best bet is to try and find just the connector or jury rig a replacement.
I'm really hoping this is the culprit. We contacted Lochinvar for recommendation on a service provider up here and they referred us to AquaTech which is the outfit handling Lochinvar in Canada. Their rep put us in contact with a guy about 20 miles away, but when we talked to him it was obvious he really didn't know Lochinvars and admitted he was "just a plumber"! Went through all the same basic stuff we've already done. He did suggest we go ahead and try changing the "throttle" on the gas valve, giving it a bit less, or a bit more. Only (really) big problem is that adjustment screw is extremely difficult to get a screwdriver on. It's hidden on the backside of the gas valve, shrouded inside a tube, and the condensate trap blocks access to getting a tool on it. Argh. I can barely get a tool (1/4" drive on extension - no handle) on it. Not even sure if I've turned the screw and if so how much - it's gonna make things worse; I'm leaving it for the original service provider who installed the gas valve to try and adjust when he comes Monday (we contacted them to come do the combustion test when I thought I had the boiler working last Wendsday). Hopefully I can rig something for that 4 pin connector before he gets here.
Good grief, what a **** show.
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" I have to admit to being confused by the schematic, it seems a lot of those paths are on the circuit board and I'm reluctant to fool with a $1000 board. "
Many folks are, so the best method of chasing out an electrical defect is abandoned for just guessing. And often that does not work out very well as your are sadly finding out.
You should not have to fool with the circuit board, just take voltage measurements at strategic points at the connector pins (back probing), however I am not convinced I'm looking at the correct wiring diagram for your unit, so making recommendations of connector pin designations is difficult from here.
As far as your Yellow arrow I believe that is a dual temperature sensor (a thermistor) where the Yellow wire is the common between the two sensors. The sensor could be bad, intermittent internal connection to its leads. An Ohmmeter may be used to test the sensor. Also the pin fitment of the connector pins may be poor so the pins in the connector do not touch the sensor pins correctly. Careful inspection may be needed. Also the crimps to the wire(s) could also be defective. Connector pins can be replaced, the hard part is identifying the correct pin and most folks do not have the correct crimping tool.
I believe the Orange arrow is another single temperature sensor.
To me, the thing is, if the sensor or the connection to it were bad I would thing that would produce an appropriate error message about that sensor. And possibly the temperature readings in the 'Status Display Screen' would not be reasonable.
*** However right next to it (Red circle) is a jumper that I believe has to be intact to supply power to the Gas Valve. I would be very curious about its integrity. ***
" While I was jiggling this connector it started to fire and I heard a clicking sound coming from this device on the side of the heat exchanger: "
This looks like a ceramic power resistor and should not make any clicking noise. Possibly it is a another temperature sensor or limit switch.
Basically only relays, solenoids, Gas Valves make clicking noises, I suspect you were hearing a relay click from the control board.
" Can it also be I'm chasing a bunch of old connections that are accumulating in low voltage? " This is possible but I don't think it is the cause in this case, since they would all have to heal for it to work and it does work once in a while.
Since you previously identified severely insufficient voltage going to the Gas Valve assembly (rectifier board) during an ignition attempt. I don't believe messing with the throttle will prove anything more beneficial than adjusting the throttle on a car when troubleshooting a dim headlight.
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System
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Monday update.
Yesterday I made a mini harness to bridge between the outlet temp sensor and it's connector. Boiler fired right up. However since the control board programing and the combustion test were due to be looked at today I let the unit cycle through to "Stand By" and shut it down. Partly because the SH temp out was at 140 degrees and the radiant floors only need to be at 110.
The service tech who originally installed the G/V came this morning and performed the combustion test, levels were correct, but when he went to start programming the control board the boiler started failing again. I showed him the mini harness I made and while fussing with that I noticed it was not just that the original connector at the sensor would wiggle (very, very, slightly but enough to show it's faulty), but that pressing on the sensor itself would start the boiler. The clicking sound I was hearing was the G/V solenoid cycling with intermittent voltage. If I held pressure on the sensor top boiler ran, let go, died.
109A_5 is that the "Auto Reset Hi-Limit" in the current flow chart? (sorry best pic available, this is from the unit's cover)
So, we've ordered a new outlet temp sensor along with a new inlet temp sensor (orange arrow above), might as well, they have to partly drain the heat exchanger to replace one so doing both for good measure.
109A_5, that loop you circled in red above is factory - it was for one of the options. That connection is tight (doubled checked!).
For right now we are back to having intermittent heat, depending on the finicky sensor connection. It will take a few days for parts to arrive and then a few more to get the service guys out to install.
I could probably install the sensor, it means drawing off the pressure and draining the heat exchanger enough to install without glycol all over the utility room.
I'll update again. Hopefully I can mark this thread "solved" Thanks again for help given!
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I think that replacing that sensor is going to repair it (assuming the connector pins are all good). Here is why, besides the physical intermittent you discovered it now makes electrical sense too.
This sensor looks like there is only three wires going to it, which seemed odd since I could not locate it on any of the diagrams, and I had no other evidence to the contrary, so I now believe that is not correct.
I believe that sensor is is two independent sensors and two different types of sensors in one housing, so must be 4 wires, one hidden from the camera.
The two independent sensors in one housing are in the Red boxes below. You would never know by looking at the wiring diagrams. The outlet temperature sensor probably works fine so no error messages from it. The Auto Reset Hi-Limit section is apparently the issue and it is in the path that supplies the 24 VAC to the Gas Valve assembly. So it all makes sense now !!!
Too bad, if the internal diagnostics were more robust it could have been an error message for a quick repair. Since the loose connection causing a severe brown-out to the Gas Valve could have been detected where the circuit goes into the Integrated control module at X5-10.
I bet the Orange wire is the one not visible in the picture above.
National - U.S. Gas Boiler 45+ Years Old
Steam 300 SQ. FT. - EDR 347
One Pipe System0 -
My son was a Lochinvar rep for a period of time. A very similar problem on a boiler like yours. The factory sent a complete new wire harness to fix the issue after the installer swapped out many sensors and board parts
Bob "hot rod" Rohr
trainer for Caleffi NA
Living the hydronic dream0 -
Is your boiler grounded properly? Plugged into an outlet or hard-wired?
Your tenaciousness is admirable!
8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour
Two btu per sq ft for degree difference for a slab0
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