Burnham Boiler Firing and stopping, then firing again immediately.

Shaggy_207

Hello, I have a Burnham boiler that is short cycling on and off consistently. It will ignite, run for about 20-30 seconds then shut off and immediately start priming and running again.
I have cleaned and tested the CAD sensor, while ignited its reading 1300-1400 Ohms, seems to be aligned correctly. 

It will do it whether my thermostats are on or off, I I’ve tried it with individual thermostats as well. Cleaned and cut back thermostat wiring at the taco box, cleaned white jumper wire on boiler control. I have a brand new (less than 1 year old) Aquastat and temp sensor installed on boiler and it is worked fine until recently. 

Edit: Should make it clear that the only reason I replaced the Auqastat was due to corroded wires at my homes weatherhead causing over-voltage to half of my electrical panel, which caused capacitor failure on the board. 

I’m also a diesel mechanic certified in DC electrical theory, with experience with AC systems. Just low on HVAC knowledge and would like some advice other than “Call an overpriced professional and wait 2 months for a stranger to come in my home”

Any suggestions? 

STEVEusaPA

Yeah. Call someone who knows what they are doing.

Shaggy_207

STEVEusaPA said:

Yeah. Call someone who knows what they are doing.

Yeah, trying to avoid a 2 month wait and expensive service charge. I’m a diesel mechanic by trade. Just looking for advice as to what I should check next. Going to clean the nozzle tomorrow when the stores open. 

Steamhead

@Shaggy_207 , what model Burnham? What burner is on it? Where are you located?

ethicalpaul

STEVEusaPA said:

Yeah. Call someone who knows what they are doing.

Just think how much easier it would be if the site just put an auto-responder with this response on each and every discussion post that people created. Why didn't Dan think of this?

Shaggy_207

Steamhead said:

@Shaggy_207 , what model Burnham? What burner is on it? Where are you located?

It’s a Burnham Hydronics Model V8F with a Beckett burner. Primary control is a Beckett Model 7505 GeniSys.

only thing I have not tried on the burner side is pulling the nozzle and electrodes out to clean them. 

It does fire, had my multimeter probed into the CAD sensor and fired the boiler, got a good reading.
edit: I am in Maine. Techs are few and far between and when you do find a residential service provider of any trade you’re put on a long waiting list as we are a very rural state.

EBEBRATT-Ed

From what I know the burner should probably run with 1300-1400 ohms on the cad cell but that is far from optimum.

Should be down around 700 ohms.

The troubling part is you say the burner starts and stop weather the thermostat is calling or not. Do you get Domestic hot water off the boiler as well??

Is it possible the problem with the wiring at the weather head caused issues with some of the other burner controls??

Shaggy_207

EBEBRATT-Ed said:

From what I know the burner should probably run with 1300-1400 ohms on the cad cell but that is far from optimum. Should be down around 700 ohms. The troubling part is you say the burner starts and stop weather the thermostat is calling or not. Do you get Domestic hot water off the boiler as well?? Is it possible the problem with the wiring at the weather head caused issues with some of the other burner controls??

It’s a combination, the boiler heats the house and hot water. Seems to be happening when the boiler itself is calling for heat. Not an issue connected to the thermostats is what I attempted to explain. I had it off and let it cool below its 175 Low temp. When the boiler calls for heat it will short cycle until it reaches my high temp setting of 190, It will stop running until the unit cools down and calls for more heat then it will short cycle as described until it reaches the set temp on the aquastat again. 

Steamhead

@Shaggy_207 , what model is the aquastat relay on the front of the boiler? Might be a Honeywell, a Beckett AquaSmart or a Hydrolevel HydroStat. Post a pic if you're not sure.

Shaggy_207

Steamhead said:

@Shaggy_207 , what model is the aquastat relay on the front of the boiler? Might be a Honeywell, a Beckett AquaSmart or a Hydrolevel HydroStat. Post a pic if you're not sure.

The aquastat is a Resideo, it was a direct replacement for my failed Honeywell that’s now no longer in production. 

Shaggy_207

Pressures are good, I installed a brand new expansion tank last year which solved my gargling heater issue along with new vents.

Steamhead

When the burner stops too soon, get your voltmeter and see if there is 120V between the burner terminals- probably B1 and B2 but I can't see them in the pic. If not, the control is bad. If so, get a pro to look at the burner.

SuperTech

Why would you want your low limit set to 175⁰?

I'm not doubting that you are mechanically inclined, but I doubt you have the tools to properly check combustion, pump pressure, Z dimension setting, draft and several other things that affect the cad cell reading. There's a limit to what even the most mechanically inclined homeowners can do safely. A good oil burner tech can not only solve your problem pretty easily but prevent future problems while he's at it. I'm sure your oil provider has 24 hour service available that doesn't take two months.

Sometimes you gotta swallow your pride and know your limits. 

STEVEusaPA

ethicalpaul said:

STEVEusaPA said:

Yeah. Call someone who knows what they are doing.

Just think how much easier it would be if the site just put an auto-responder with this response on each and every discussion post that people created. Why didn't Dan think of this?

That would work for you too. Shouldn't you be bashing oil right about now?

I will never help someone work on an oil burner who doesn't have the proper training, skills & tools, no matter what their regular trade is or how handy they appear. It's quite dangerous, with possible catastrophic results.
I don't feel the need to try to prove how smart I am by dispensing information.
Sometimes the best help is to get someone in there who knows what they are doing.

I am empathetic to peoples troubles, but I'm tired of hearing people don't have the money, they can't find a good person, it's a 2 month wait...blah blah blah.

I've never heard of a full service oil company, who has a customer in good standing, making them wait 2 months for service. That's half the winter. There's always more to the story.

ethicalpaul

There is some truth to what you say, Steve, I don't like oil, when there are alternatives which are better. My mom's house has oil--there's no NG. I could put an LP tank there but there's no benefit over oil there.

I hope that I put some thought and logic into my replies, although there are certainly some where I have failed in that.

And I understand your thinking about never helping people in dangerous situations, but honestly, every day there are HVAC pros/contractors who come here with similar kinds of questions. Do they get turned away so sharply?

Your response was pretty stark--I can tell you are tired of reading certain posts as you described above. We all are at times. Have a good holiday.

Papalegba22

What's the point of having this forum if there's people that refuse to help? I'm also a DIY guy when it comes to my Burnham oil burner but I've managed to keep it going for over 10 years now with many headaches. The only reason for my success is from forums like these. I don't own any special equipment but I'm mechanicly inclined. I'm a Electrician by trade and I get to talk with many Hvac guys and all say I'm fine with what I'm doing 

Jamie Hall

MikeAmann said:

@Papalegba22 Because a little knowledge given to a person that can't fully understand the answer can cause dangerous and even deadly results, no matter how well-intentioned.

One of the hardest things to do on this forum is judge just how good and talented a person is in one area or another of the work that needs to be done. Most of us have a pretty good notion as to what we are good at, great at, marginal at, and shouldn't touch with a pole. But judging that in another person based on the questions asked... difficult. I am sure, @Papalegba22 , that you at least think you are very skilled at the maintenance of oil burners. I, for one, am surely not. Getting them to work properly in a given boiler setup is a fine art. Very few people are, however, and in my humble opinion that is an area which is much best left to people with a lot of training and a lot of experience out there.

And yes, HVAC contractors do sometimes get turned away -- or, more often, referred to others.

And @STEVEusaPA last comment, that he has never heard of someone in trouble who has been turned away from help -- provided they are known to be a steady customer in good standing. As he says, there are always two sides to an interaction between a service person and a customer, and there simply aren't enough service people out there who have schedules which are so open and funding which is so generous that they can bail out someone they never heard of before. It would be nice if that weren't the case -- but it is.

MaxMercy

The CAD cell readings are high, but not causing the cycling issue (too high CAD readings cause a single even lockout that *must* be manually reset).

realliveplumber

If he can fix a diesel engine, he could learn how to service and repair an oil burner.

He has specialized tools for diesel engines, he would need to buy specialized tools for oil burner service. And learn the proper procedures.

The means of which he learns those procedures are up to him.

Its not brain surgery.

Jamie Hall

realliveplumber said:

If he can fix a diesel engine, he could learn how to service and repair an oil burner.

He has specialized tools for diesel engines, he would need to buy specialized tools for oil burner service. And learn the proper procedures.

The means of which he learns those procedures are up to him.

Its not brain surgery.

This is a very good point. Provided you read and understand all of it. It is very likely indeed that if someone has learned to fix a diesel engine, he or she would be very well qualified to work on that type of diesel engine (not all diesels are created equal). That, however, only indicates that he or she has the aptitude for that kind of work. Would they be equally qualified to work on a modern computer controlled DFI gas engine? Not without the learning. Would they be equally qualified to work on an oil burner in someone's house? Not without the learning.

One of the least appreciated marks of a really competent person -- and it doesn't matter whether it is diesel mechanics, oil burners, brain surgery, nuclear physics, or whatever -- is that they have confidence in what they know how to do -- and they have a clear and humble appreciation of what they don't know, and they don't venture there.