Oil Burner Issues

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Just that I kept that in mind...



This is for hot water, not hot air.

And, in the beginning when I tested the aquastat, it is exactly what I said. I read online somewhere that L1/L2 could test the low water cut off, and B1/B2 could test something else. There are two switches. I have to have them both on for it to run. When I tested those terminals, I only had one on. The system was not burning it simply had power to the system. I tested the L1/L2 and got a reading of 0, and when I tested the B1/B2 there was a reading of 120vac.

Where exactly did you test L1/L2? If it was at those terminals in the stat, and there was zero there, then there should also be zero at B1/B2 since the power to those needs to come through the L1/L2
first.
 
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Scratch a little. When I tested those L/B terminals the two switches were on but the system was not burning. I had to check my notes on that one..
 
Where exactly did you test L1/L2? If it was at those terminals in the stat, and there was zero there, then there should also be zero at B1/B2 since the power to those needs to come through the L1/L2
first.

There was most certainly a 0 read on the L1/L2 when I tested them... I got 120 on the B's and 0 on the L's. The Aquastat I ordered (this last one) was used but tested and I have not tested it with the meter yet.

I will test again. So what does that mean then? If this is the case?
 
There was most certainly a 0 read on the L1/L2 when I tested them... I got 120 on the B's and 0 on the L's. The Aquastat I ordered (this last one) was used but tested and I have not tested it with the meter yet.

I will test again.

So how is it possible to get power out of a device (the stat) with no power going into it?
 
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Faulty circuitry... LOL. I will go test and take a picture.. If you have some alternative option toss it out there. I can test even switching the live and ground to find a read of 0. Well it did the last time I tested it.
 
Ok so I tested them again and there is power at all the terminals now. So I referred to my notes and images and it did give me that false reading last time, and those L terminals go to the low water cut off, which I have replaced since I last tested those terminals.

And, the circulators are not powered by the blue box they are hard wired into the 120 volt system of the house..
 
Because there is some confusion..understandably as I have been developing knowledge and stats as I go, I will make up a new status.

My issue is that my boiler is overheating in a short amount of time, or, only running a small (15min) cycle before shutting down due to the internal thermostat in the aquastat. This short burn time is not allowing for the water systems of the house (or zones) to see any hot water, the only signs of hot water are the surrounding pipes and area (in its days of an operational condition it took around 45 mins to get hot water to the zones.)

Adjusting the limits does not change the outcome, even when set low it will still fire and heat up to the 220 degrees and shut down. When it shuts down it will not fire back up until hours later once it has cooled down.

The circulators are working, and are hard wired into the house, and have been purged to check for water. The L1/L2 & B1/B2 terminals on the aquastat were tested and give off the 120 volt read. The thermostat is jumped, and their are technically two, one for the house call (forced hot water usually off), and another for domestic water. I think it is still in call for heat once it shuts off, but I am not positive right now.

When I power on the switches, the intermittent ignitor starts in a tripped mode with the red light lit. At this point there is power to the system but the burner is not burning. If I hit that reset the system will then fire and burn. It will run through the quick cycle until it hits the hot mode which it then cuts the power to all of the components so that everything seems dead, and the power will not come back until the system has sat for at least a few hours and cooled.

The following parts have been replaced:

Nozzle
Ignition cover
Intermittent Ignitor
Aquastat (used but tested)
Low water cut off
CAD censor
Nozzle
Oil Filter
Large control box

As far as major components, the only ones not replaced are the circulators and the blower motor, and the main burner box. I do not have any way to tell if the blower motor is working or not. This is my next lead at the moment...
 
The one thing that makes me wonder is the limits thing. Correct me if I am wrong, but the high limit turns on and off the system right? It it not a temperature based "if / then" execution system? Say 'if' system reaches this temperature, 'then' do this.. and the low limit has a function in this too. But, when this system runs, it seems like these have no say or affect. I could drop these to 120 and the system will do the same, it will run up to 220 until it over heats and powers off....

What does that mean?? Is that normal?
 
(The suggestion that the oil burner motor might be bad is aimed at the possibility that the motor is overheating and is cycling on its internal thermal cutout, even though it is able to run for a while. If the motor was bad as in kaput then you would know it because there would be no noise [other than perhaps an ominous hum], or firing of the burner. Since the boiler is heating up then it sounds like the motor is probably OK.)

Two things don't make sense. One is that the boiler heats up to 220 no matter what the LO and HI settings on the aquastat are. The other is that if the circulators are running, why isn't the boiler cooling down accordingly? (And a third: if the aquastat high limit isn't turning the burner off then what is? Is there a low water sensor or a separate fail-safe aquastat in series with the power supply to the L8124A aquastat that can interrupt power on overheat?)

The aquastat HI limit should shut the burner off according to its setting. If it is not then the aquastat is not functioning correctly.

If you remove one of the wires connected to the aquastat T-T terminals (so there is no call for heat as far as the aquastat knows), the burner should come on an off according to the aquastat LO setting. If it does not then the aquastat is not functioning properly.

Once you're sure the aquastat is working then you can figure out why the circulators are not moving heat away from the boiler.

(When you fiddle with HI and LO be sure to keep HI substantially above LO. Study "Fig. 12. Relationship of setpoints and differential." in the aquastat sheet to understand how that works.)

You may want to print off a copy of the aquastat schematic:

https://customer.honeywell.com/resources/techlit/TechLitDocuments/95-0000s/95-6571.pdf

Study the schematic and use your voltmeter to convince yourself you know how it works and what voltages you should see at various points, vs. what you do in fact see. (Be sure you're looking at internal schematics for the L8124A as opposed to the other flavors.)
 
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Is the exhaust a natural draft flow, or is there a power venter on it?
I had similar issue with forced air furnace heating up, but hitting overlimit and shutting down, traced it to the power venter gone to shat, and replaced it, then all was well.
Just a stab. May not be your issue, but figured I'd throw that out there.
 
I'll begin new again, by commenting on your new status post with things I see are wrong or confusing. These go along and in addition to with what ewdudley posted.

My issue is that my boiler is overheating in a short amount of time, or, only running a small (15min) cycle before shutting down due to the internal thermostat in the aquastat. If the stat is working right, it will shut it down per the settings on it. So I don't think it is shutting down due to the internal thermostat in the aquastat.

This short burn time is not allowing for the water systems of the house (or zones) to see any hot water, the only signs of hot water are the surrounding pipes and area (in its days of an operational condition it took around 45 mins to get hot water to the zones.) It doesn't matter how short the burn time is - if the boiler is getting hot, the zones should see hot water. So there's a problem on the circulation side of things. And if it took 45 minutes to get hot water to the zones in 'operational condition', then there was a problem then too, because your zones should see hot water in just a couple of minutes if the boiler is hot and there is a call for heat from the zones.

Adjusting the limits does not change the outcome, even when set low it will still fire and heat up to the 220 degrees and shut down. When it shuts down it will not fire back up until hours later once it has cooled down. At what boiler temp does it fire back up again?

The circulators are working, and are hard wired into the house, Wired how? In order for your system to work right, the zones have to communicate with the boiler to tell it when they need heat. We still don't know how that is done here. The fact you have the thermostats jumpered to give a constant call for heat just adds more confusion because that shouldn't be done. So it is a sign of improper system operation and controlling.

and have been purged to check for water. That still doesn't mean the water is flowing. You could have an airlock or bubble somewhere in your zone which would prevent flow. How much PSI is in your system? Do you have more than one pressure guage? Because they can fail - when mine failed, it failed with the needle stuck on normal PSI reading.

The L1/L2 & B1/B2 terminals on the aquastat were tested and give off the 120 volt read. The thermostat is jumped, Why?

and their are technically two, one for the house call (forced hot water usually off), How does the house heat then if the forced hot water is usually off? How is it turned 'usually off'?

and another for domestic water. I think it is still in call for heat once it shuts off, but I am not positive right now. This is also confusing since if you have the thermostat jumpered, there is always a call for heat.

When I power on the switches, the intermittent ignitor starts in a tripped mode with the red light lit. Does it also do this when you turn on the power when the boiler is cold? But this is another sign of multiple issues - the red light shouldn't come on unless there was a problem with the burner itself. Usually when the cad cell interrupts the burn, or if the points don't ignite the flame, or you lose oil pressure. Do you have steady constant oil pressure & what is it?

At this point there is power to the system but the burner is not burning. If I hit that reset the system will then fire and burn. It will run through the quick cycle How quick? How much time?

until it hits the hot mode which it then cuts the power to all of the components so that everything seems dead, So at this point, is there still 120 at L1/L2 &/or B1/B2? If there is now no power at L1/L2, then there is something else cutting power before it even gets to the aquastat. If there is power at B1/B2, then the burner itself is cutting out. But at that point, your circs should still be running and your boiler should cool off rather quickly.

and the power will not come back until the system has sat for at least a few hours and cooled. You need to find out what all still has power at this point (when it cuts out)..

The following parts have been replaced:
Nozzle
Ignition cover
Intermittent Ignitor
Aquastat (used but tested)
Low water cut off
CAD censor
Nozzle
Oil Filter
Large control box


As far as major components, the only ones not replaced are the circulators and the blower motor, and the main burner box. I do not have any way to tell if the blower motor is working or not. This is my next lead at the moment... If the burner is heating the boiler, then the blower is working. That is what makes most of the noise when the burner starts. It can't burn without the blower running.

There are multiple issues here - you really should get a burner guy in. A decent one should be able to figure out what's wrong in short order. Pretty hard for us to do from here without precise systematic trouble shooting & tracing feedback. And more pictures. And maybe an accurate schematic. Of your whole system.
 
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Thank you for that, Maple1. I know it all sounds confusing but I am learning about these for the first time.

As far as I know regarding the thrermostats, there are two, one manages the part that calls for heat to the forced hot water system, and the other the tap.. (AS FAR AS I KNOW). When we moved here it was set up like this, and the people used it by leaving the house thermostat off and jumping the second one. It worked for a long time like this.

I agree that there could be a circulator bad too. There must be several issues and I have been working on getting in a pro. But my latest estimates were 300$+ (thats what the boiler guys around here want for a service call). I am going to snap a few more pictures so you guys can see what is going on....
 
I am in CIS and study circuitry, it would be a little hard for me to mix up 4-6 wires in a aquastat....

You have no idea of wiring, Reading schematics, Wiring diagrams. Not a clue! Don't even think of getting huffy, after stating no power in but magic power out.

With all the components that you have already replaced, You are already over the price of a service call, except that you have had your mits in every aspect of boiler. So it will be 10 times harder for the tech as he has to go over every bit of the system wich is probably a good thing because if your terminology is 1/2 right. You have a cluster XXck, hacked in, home owner install from hell.

That felt good, most infuriating, stressful, confusing, thread I have ever read. Sorry if I offended you, but it had to be said.
 
Take a deep breath. >>
 
You have no idea of wiring, Reading schematics, Wiring diagrams. Not a clue! Don't even think of getting huffy, after stating no power in but magic power out.

With all the components that you have already replaced, You are already over the price of a service call, except that you have had your mits in every aspect of boiler. So it will be 10 times harder for the tech as he has to go over every bit of the system wich is probably a good thing because if your terminology is 1/2 right. You have a cluster XXck, hacked in, home owner install from hell.

That felt good, most infuriating, stressful, confusing, thread I have ever read. Sorry if I offended you, but it had to be said.


That needed to be said! Thank You
 
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