No lights for call for heat on s8610u but my dampener opens and closes like it should.

Joeguy

Heat worked yesterday but now for some reason the call for heat signal seems to not be making it to the controller, or atleast the lack of green light suggests so. My dampener opens and closes when i turn the heat on and off so im not sure whats going on here. Pretty sure the wiring is a bit off from what it should be, from what ive seen the 24v should have a wire going to the dampener but i do not. My dampener is a GVD-6 and has the black and brown wires directly connected to the 24v transformer (C and Load) and the orange goes to my pressuretrol and yellow goes to low water safety then to some resistor looking things, then to the TH/w terminal.

Joeguy

Actually after poking around a bit more i think my transformer is bad, now to try and find one locally i hope.

JUGHNE

If you have only one transformer and your damper motor works, it is not the transformer.

Check pressure control, low water cut off, blocked vent switch and burner flame roll out fuse.

Has the pigtail been cleaned recently?

JUGHNE

Depending upon how your control wiring is connected, in some cases the damper would not be called to operate unless the safeties mentioned above are closed.

The low water cut off may have a probe into the water, that requires cleaning at times.

How much water shows in the sight glass?

HVACNUT

If the transformer was bad, the damper wouldn't operate.

There's a little switch on the damper. Raise the thermostat so the damper opens. When the damper is fully open, flip the switch to manual. If that starts the burners, then it's a bad end switch in the damper. It's safe to leave the damper open until you can get a replacement.

Is the circulator running? If not, it's likely NOT the end switch in the damper, but maybe the relay.

If the circulator is running, and switching the damper to manual doesn't do it, then a safety probably tripped and you'll need a qualified tech.

JUGHNE

Is this steam? My replies are based on this being a steam boiler.

HVACNUT

https://forum.heatinghelp.com/discussion/comment/1816572#Comment_1816572

Sorry, yeah, I mentioned circulator but the OP mentioned a PressureTrol.

EdTheHeaterMan

Depending on your boiler make and model, your wires may be just fine. I also agree that the 24 VAC transformer is not defective if the damper motor is operational. That damper motor uses 24 VAC to operate.

So i need more infor to help. Boiler Info Make, Model, Size

Joeguy

I did clean the pigtail and stuff out a month ago trying to get ready for the cold, maybe it needs it again though. I went through with a multi meter and it seems like both the pressuretrol and low water safety are working alright. The transformer is giving me like 1.74 volts, also i took it out of the junction box its mounted in and there are some pretty loose windings. I have no idea how the damper motor is working but im pretty sure this transformer has something wrong with it everything else seems good. I have a buddy who does this stuff for work bringing me a new one today, if thats not the fix ill get you guys more info.

Joeguy

Alright probably to no surprise that did not fix it, my buddy gave me a new thermostat for free too and i installed that, still not fixed. Something odd to me is that i have 26v across the thermostat wires untill i call for heat then it goes to 0v but the damper still opens is that how its supposed to work? The boiler is a PSB-5D and here is a picture of the wiring diagram on it. All the wiring matches up on mine except the Wires that normally go to the (2) terminal on low water switch are just tied together instead, but i have a different style of auto feed/safety cutoff and its worked so far so i assume its alright. It looks like i could open the damper, unplug it, and jump orange/yellow to try and rule out that being bad but im not 100% sure so i didnt try yet.

EdTheHeaterMan

According to the wiring diagram, the only thing that will keep the auto vent damper from operating is the thermostat and the pressure control. So those two items are not the problem. Once the damper is open there is a safety switch that closes in the damper. That is the first thing to check. Is that switch closing to send 24 VAC to the burner circuit? That is done by attaching your 24 VAC meter leads as shown in the diagram.

If you do not get 24 VAC at the wire nut or the 1 terminal on the LWCO, then you have a bad damper motor and that needs to be replaced. If you do get 24 VAC at the 1 terminal then you follow the circuit to the 5 terminal on the LWCO.

This is the next stop on the electrical train to the gas valve. If the water is low, then add water. If you get 24 VAC to on the LWCO then move to the next stop. That would be the Roll Out switch, Purple then Blue then to the Spill Switch Green then Yellow Then to the S8600 5 terminal (24 V) Red Lead.

When you stop getting 24VAC reading on the meter, you have found the open contact or broken wire. That is what you need to fix.

Joeguy

Well first off im dumb and had my multimeter on the wrong settings….oops. So it seems like voltage does not make it past the rollout switch so i guess thats bad, should i jump across it to keep testing the rest of the system now i guess? Also just looking on amazon for replacements and cant really find an exact match, and ebay only has used ones, its a Microtemp 4d4283a. Which would you get for a replacement?

Steamhead

What make and model boiler is it?

Joeguy

PSB-5D Dunkirk

EdTheHeaterMan

When you jump across the roll out switch, does the burner operate?

If yes, then you need to find out why the rollout switch tripped. Is the vent blocked, is the HX blocked? Was/Is there a downdraft in the flue or the flue connector?

Those safety devices are there for a reason. You need to find the reason it failed!

This is your part. It is a fusible link. One and done.

https://www.supplyhouse.com/Utica-Dunkirk-14629002-291F-Thermal-Cutoff-Rollout?_br_psugg_q=14629002

Get two they are small.

You may need a mirror and a flood light to look up inside the heat exchanger for a blockage of carbon/soot build up between the cast iron sections.

Joeguy

It does with with it jumped, there is also some chunks of either something that got really really burnt or its big chunks of soot, they ended up down by the burners. I reached my hand up into the exchanger and its definitely got a good coating of soot but i cant tell too much just by feel. I do not feel a downdraft. Guess i need to get this thing a really good clean, or figure out how to do it myself. At least i know i dont need any more parts ha, i got 2 of those on order.

Steamhead

It definitely sooted up, @Joeguy. Time to call a pro. Where are you located?

Joeguy

SW Pennsylvania

EdTheHeaterMan

There is carbon in between the cast iron sections. you need to do two things,

1. Remove that soot
2. Find out why that soot got there in the first place.

To remove the soot, you will need to remove the vent damper (16) top cover (13) and then the flue collector (14) to access those flue passages with boiler cleaning brush and a SootMaster vacuum or a shop vac with a extra collector bag.

You may want to remove the burners at the bottom to clean them and vacuum out the combustion chamber (5) before replacing the cleaned burners. This is a real project and you may want to get a Pro to do it. The guys that work on oil burners have the necessary tools to do this job.

Once the boiler is cleaned and back together, you will fire up the burner and need to have the flame tested with a combustion analyzer (another expensive tool that oil burner guys have) to see why the flame made so much soot the leat time it was operational.

You will want to look at what has changed around the system since the last time it operated properly.

1. Has a tree grown higher that the top of the chimney?
2. Was the basement refinished/remodeled?
3. Was there an exhaust fans added to the building?
4. Was any work done in the home that created excessive dust to accumulate on the burner air intake?
5. Was the home insulated new windows installed or sealed up in any fashion?

These items and more can cause there to be insufficient combustion air. Without enough air for combustion the flame will burn rich, and dirty, and leave massive amounts of soot behind.

Joeguy

I did fix a window that was just held in with a brick in the room with the boiler but the tops of the walls are not sealed so it technically has air from all the other rooms too i would think. Its a pretty old house and there is alot of dust down there on top of everything. Also ya i may just be paying for someone to clean it, i mean i can atleast hit it with my shop vac and a brush if they want a crazy amount of money or something though.

SuperTech

You have a dangerous situation with that boiler. That fusible link saved everyone in your home from carbon monoxide poisoning. You need to get it professionally repaired by someone who is trained in combustion analysis and equipped with a digital combustion analyzer. I don't think this is something you should attempt to DIY.

Joeguy

Alright ill see if i can find someone that specializes in it. I have had a few people over the years come look at it and I end up knowing more than them, so my luck with help has not been great.

Joeguy

Good news, had my buddy come back and helped me clean all the soot out and also the blockage in my chimney….anyway a good 5-6 hours of cleaning later and my CO levels went from 2700 to 10 or less ppm and there was no crack thankfully. My actual like burners had a bunch of rust/soot/dirt packed in them so we cleaned those aswell and now i got a nice clean blue flame.

EdTheHeaterMan

Can you post the combustion analysis numbers for your finished job? CO2 and O2 numbers along with the stack temperature and the draft readings. The CO went from 2700 to 10 PPM. That is a big improvement, Sounds like you are on the correct path.

When you put the flue collector back on top of the cast iron block, how did you seal it? High temperature RTV cement or did you use new gaskets from the factory? You don't want any flue gas leaks getting inside your home.

Joeguy

My buddy did not print the paper for the test but he did come check it again to be double sure and he says its looking good. It was sealed up with some kinda hight temp red colored silicone.