Burnham Steam Boiler Help

lwalsh4

Hi all - new to this site and looking for boiler advice. Thanks in advance!

I have a Burnham low pressure boiler, steam heat, natural gas. The silver tag says: ANS Z21-13; 1989; Model no. 404B; serial no. 12 074015. I'm not sure when it was installed as it was in house when I bought it with no info. Any idea what year this is from? I can't find any info online for this.

Currently it will not stay on. I can light the pilot, turn it on, turn thermostat up, heat kicks on and all burner light up, and after about 2 minutes the whole thing, including the pilot kicks out. Seems like a safety feature, but i'm not sure what could be causing it to shut down. Anyone hear of something similar to this? I try this several times and get the same result. I've changed the thermocouple already.

Secondly, depending on the age of the unit (I'm guessing its at least 20 years old?), I'm wondering if I should invest in repairing the unit or if I should buy a new boiler for the house. If the best option is to buy a new boiler, curious what the best brands are that I should be looking at. Otherwise is there a part I should try replacing first, like the gas valve?

Other info: Boiler heats a 2 bedroom apt that is appx 950 sq ft. I shut it off in the summer since it only is used for the heat (hot water is separate). There are 4 radiators in the apt. The flue is connected to the chimney. I live in New England so currently its COLD! 18 degrees tonight....got space heaters going for my warmth, but a little nervous about the pipes freezing if I don't get this figured out quickly.

Abracadabra

Thermocouple flaky? Is it in the pilot flame properly? Is the pilot flame stable? Sufficient to cover the thermocouple?

Jamie Hall

It probably is one of the safety cutouts. The question is, of course, which one? And then, why? Can you post pictures of the boiler, and the way it is connected to the chimney, and the controls? Then we can begin to think about what safeties it has -- and what might be happening.

Where in New England are you? It's a fairly large area, but there are a number of really good men we know of in the area, and one of them might be near enough to be helpful to you.

lwalsh4

Yes, the pilot will light and stay lit if I don't turn the heat on. It would stay lit for hours. Once I turn the thermostat up and triggers the boiler to turn all the burners on (there are 5 burners), it will only stay on for about 2 minutes then the whole thing shuts off. Doesn't sound like the pilot to me, but I'm a novice when it comes to boiler issues.

lwalsh4

Thanks Jamie Hall. I'll go and take pictures now. I live in Medford, MA, just north of boston.

Jamie Hall

There are at least two possibilities which occur to me rather quickly -- one is a loss of gas pressure for some reason, but I would think that would happen faster. The other is a stack safety switch, which is intended to ensure that the thing is exhausting properly. It could be defective. It could also be telling you a true tale about the chimney or the flue.

Do you have a CO detector nearby?

Abracadabra

If it's a standing pilot, would the safety switch kill the pilot? Maybe excessive draft blowing out the pilot?

Gsmith

is there water in the boiler up to about the middle of the glass tube? MIght be low water level.

lwalsh4

Not the water level. We keep it up to the middle of the sight glass. Also we drain the water frequently in the winter - try to do it once every two weeks, otherwise it gets clogged up with muck.

I don't think it's a draft, its in an enclosed basement with no windows open. The pilot will stay on as long as the heat/other burners don't ignite. It is a standing pilot.

Two CO detectors in the basement, both were tested yesterday batteries work. Working on posting pics now.

lwalsh4

Any idea how old this is? Pics attached

JUGHNE

It could be possible that the main burner gets shut off by some safety switch. When the main valve snaps shut the burner could "whuff" out the pilot flame. If so you might hear the thermocouple click the gas valve pilot portion off after a minute or two.

That backdraft "whuff" or lack of flame on the T-couple is the only thing I could think of that would shut off the pilot.

Your pilot flame may be too small to survive the main burner shut down. Dirty pilot or low gas pressure.

lwalsh4

Any ideas about how to correct that or who to call ? Thermocouple is new so it shouldn't be dirty causing the low flame.

lwalsh4

Pilot flame attached

neilc

looks like the thermo couple is cross threaded into the gas valve,
that might be a weak connection there and while strong enough to hold the pilot, is too weak a signal for the full gas valve.
Try reseating that squarely,
back it out and feel for the thread to click and pay real attention as you carefully screw it back in, squarely

JUGHNE

When the mail burner comes on could the draft from that be lifting the pilot flame off of its burner and leaving the T-couple out of the pilot flame?
After your 2 minutes then T-couple shuts down all gas flow.
T-couple has to stay in the fire

lwalsh4

So a weak connection would be able to light the pilot but not be strong enough to hold the burners? And therefore not a safety issue but a connection issue?

Good eye on the cross thread we unfortunately can't back it out, the gas valve was stripped and the plumbers pinched the connection at the gas valve to keep the nut screwed into the gas valve. It worked for about month after they did that. Maybe it became loose and not a safety shut off issue? They told us Honeywell no longer makes our gas valve (I found it hard to believe there wouldn't be a replacement part for obsolete parts). So maybe we should try someone else to find a replacement to our gas valve. Our old one is a vr800c 1513 which is no longer made. Thanks!!

Fred

I'm gussing what @neilc mentioned above is the problem. Take that off and screw it in so that it is square. Screw it in hand tight and then 1/4 turn with a wrench. There is a magnetic connection between the gas valve and the Thermo-coupler. No gas there.

Abracadabra

Manual in case you need it.

The valve is replaceable. I'm sure honeywell has an alternate.

A V800C1052 might work, but to be sure I'd have someone come in to take a look at it. Don't know what the capacity of the existing valve is. I'd recommend you call in a pro to do a combustion analysis to make adjustments once it's replaced. You may need to contact Burnham for help on an approved replacement valve.

lwalsh4

Thanks everyone!! Attached is the info on the gas valve. Hopefully that's all it is. Any ideas on how old the boiler may be? Replacing the whole boiler has been on my radar but if I can't get 5 more years out of it I'll wait! I've tried searching the serial number / model and have had no luck.

rbeck

If interested the boiler a 404B was shipped Jan, 1992. The current gas valve is a Honeywell VR8300C4027B if needed.

lwalsh4

Awesome thanks for the info rbeck. Curious how you knew that?

neilc

lwalsh4 said:

Any ideas about how to correct that or who to call ? Thermocouple is new so it shouldn't be , , , (cross threaded).

so you changed the thermo, or the plumber did?
I would think the plumber would owe you the gas valve, or thermocouple if they buggered it, pinched it, or whatever was done there.
I don't know if you call them back, or another, or someone from this site,
someone crafty might be able to get that to seat again, but it would need to be seen first and determined from there.

bob_46

I notice you have a spill switch on the draft diverter(the big bell shaped thing in the flue pipe) . With the main burner fired hold a lit match at the bottom edge of the diverter, the flame should be sucked in it should not snuff out.

bob_46

The burners look filthy I hope the black stuff isn't soot. Put a mirror in the boiler so you can look up at the sections if you can see any black the boiler has to come apart and be brushed out.

Fred

The 4B series Burnham boilers were built like tanks and hold up extremely well. I have a 411B that is 34 years old and still going strong. Have the boiler serviced and cleaned. It likely still has more life left in than most new boilers.

lwalsh4

Here's a pic of the inside with the mirror @bob Not sure what it's supposed to look like

@Fred good to know - haven't had it serviced in a couple of years. We only flush out the water once a week or so in the winter. A plumber services it? I never know what type of person to call for the boiler

JUGHNE

When you flush out, what valve do you use? The garden hose valve or the yellow "Webstone" valve?

lwalsh4

@JUGHNE the yellow handle valve to flush it out

Fred

Where are you located? Try to find a good steam Pro and establish a relationship with them so you can depend on then to take care of any real problems if/when they occur. We may be able to give you the name of some Pros on this site in your area.
The underside of that boiler looks pretty good. There are wire clips on the front end of those burner tubes. If you are comfortable doing it, turn the power to the boiler off. take the clip off. Lift the back of the tube up and slide it forward. Once it is out of the rear slot, slide the burner tube back and lift it out of the boiler.Take the burner tube out and clean it. You can run a damp cloth through it or blow compressed air through the burner slots to clean dirt/dust out of the slots where the flame lifts through. Clean the outside of the tube, use a vacuum cleaner to clean the floor of the burner pan and reinstall the burner tube. Slide the front of the tube onto the orifice then slide it back and drop it into the rear slot. Put the clip back on. Move on to the next. If you are not comfortable doing that, let's get you someone who knows steam.
That McDonnell Miller Low water cut-off should be checked and cleaned out too. That's probably left to a tech unless you are mechanically inclined. It needs to be taken apart and scraped out, float checked, switch checked and new gaskets installed.
Did reinstalling that thermocoupler in the gas valve solve your original problem?
EDIT: That pigtail under the Pressuretrol should be cleaned out as well. If it is clogged the Pressuretrol can't see actual pressure in the boiler.

lwalsh4

@Fred I am located in Medford ma. Thank you for the tips. I feel comfortable cleaning the burner tubes I already took one of them out. I thought about looking into the pig tail as well but since I haven't done that before wasn't sure what I was getting myself into. I would not feel comfortable cleaning the low water cut off - we drain the water until it's clear again, but have not taken it apart to clean.

If you have any recommendations of people in my area I'd appreciate it.

Replacing the thermocouple fixed the first problem, but the gas valve was stripped where the nut goes in, so the plumber just pinched the area where T-couple screws into the gas valve to get it to hold the connection. Since it's not working anymore (pilot will light but after burners go one everything shuts off) someone on here mentioned the connection isn't strong enough/probably loose. I found a technician who can get a gas valve and replace it - I'll ask him about servicing the other parts you mentioned as well. If not a recommendation would be great. Would be great to keep this going for another 10 years! How often should I get it serviced?

Fred

It's a good idea to have it serviced once a year. @Dave0176 is in MA., I think. Let's see if he covers your area. There are others on this site as wll. Go to the Main Site, on here (tab at top of page) then "Find a Contractor" tab and put your zip code in.

Sunburysnyder

Wow. This is a great thread. I too have exact model with same valve. What did you end up,doing? I nearly had to replace valve this weekend... I could not get thermocouplermto stay in stripped threading. Main problem was thermo coupler needed to be honed down in one area with Dremel so it could barely catch threading. I did find another vr800c on eBay but the next four digits don’t match up. Does it have to be 1513 to be compatible... I looked at replacement valve that honey well suggests... they want over $250 for it....

Fred

@Sunburysnyder , You need to use a recommended replacement valve. The price may seem costly but it's a bargain relative to your safety and that of your family. I know many of them look alike but it's their operation that is critical.

Steamhead

lwalsh4 said:

Awesome thanks for the info rbeck. Curious how you knew that?

@rbeck is the director of training at Burnham, and is one of the best in the business.

Any time a burner is serviced or parts replaced, a combustion test is mandatory. There is no other way to make sure the unit is operating safely. This is going to mean a visit from a pro, but it's worth the cost. The same pro could likely come up with ways to make your system use less gas.

There are a bunch of good Steam Men in the Boston area. Click on the Find a Contractor link at the top of the page to locate them.

lwalsh4

@Sunburysnyder we replaced the gas valve, it worked for a little bit then we started having the same issue again with the pilot going out. We spent a little over $200 on the gas valve, plus the paying the person who replaced it. Unfortunately that didn't solve the problem. We debated our best course, and decided not to put any more money into the boiler given the age. I know I'll get some negative feedback switching from steam and that these systems can last 30+ years, but in Mass there is a program that gives rebates and 0% interest free loans to replace heating systems. We got quotes for all types of new heating systems including a new steam boiler, but for our situation what made the most sense was a Lockinvar combi heat/hot water system with baseboard heaters. Sorry that doesn't probably help your situation!

KC_Jones

It's your house and you can do what you want, we only have opinions around here.

I am having a hard time understanding how replacing the entire system and all the repairs that will come with the change, makes more sense than fixing or replacing the steam boiler.

You better make sure they design and install the system properly. If you are doing a mod/con make sure they size it and they system to keep it condensing as much if not all season.

They will need to install a lot of baseboard to make sure you can condense all season.

For all the steam horror stories on this site there are just as many hot water horror stories.

Here is a good example of what happens when they don't do things properly.

https://forum.heatinghelp.com/discussion/157697/hot-water-boiler-and-system-repipe

Jamie Hall

Just a little note for @iwalsh4 and @Sunburysnyder -- folks, it's your money and I'm certainly not one to tell you how to spend it. However, first off a steam system can easily last well over a hundred years with only normal care and maintenance. Not the boiler; they don't last as long any more (they used to, but not any more). Second, a new steam boiler and a new non-condensing hot water boiler will cost you just about the same amount of money including installation and will last about the same time. A new modulating/condensing boiler will cost you considerably more, if it is installed properly, and won't last as long. Replacing all the pipes and radiators in a functioning steam system with new piping and baseboards for a hot water system will cost you a lot of money.

I do realise the attractiveness of rebates and interest free loans -- which are paid for by your tax money, by the way -- but there ain't no free lunch and you are, to put it bluntly, being played for suckers.

lwalsh4

@KC_Jones @Jamie Hall Thank you for providing that other thread. I valued every opinion I received on this site trying to fix my original problem and I truly appreciate there is a site that people like me can come and get third party advice.

I am by no means suggesting @sunburysnyder do what we did, simply responding to sunburysnyder's question about what we ended up doing. We first tried replacing the gas valve, then replacement the system. Our initial problem (which they also appear to be having) was never fixed which answers their question.

If the system fails and we made a mistake, that is fully on us and I will back to this site for help and own up to it! We also had a hot water tank that was beyond its life expectancy that we took into consideration as well. We have heat this winter as opposed to last year, and cannot undo our decision.

I fully understand that I am paying for the rebate/loan and understand how it all works, please don't call me a sucker.

Steamhead

lwalsh4 said:

@Sunburysnyder we replaced the gas valve, it worked for a little bit then we started having the same issue again with the pilot going out. We spent a little over $200 on the gas valve, plus the paying the person who replaced it. Unfortunately that didn't solve the problem. We debated our best course, and decided not to put any more money into the boiler given the age. I know I'll get some negative feedback switching from steam and that these systems can last 30+ years, but in Mass there is a program that gives rebates and 0% interest free loans to replace heating systems. We got quotes for all types of new heating systems including a new steam boiler, but for our situation what made the most sense was a Lockinvar combi heat/hot water system with baseboard heaters. Sorry that doesn't probably help your situation!

That was a waste of taxpayers' money.

Tim McElwain

Before you spend anymore money or time have a professional look at the system. The VR8300C gas valve is a step open gas valve by the way. It should open on low fire and then 10 seconds later go to full fire.

What were your millivolt readings on the thermocouple they should be 25 to 30 miliivolts open circuit, 15 millivolts closed circuit and 15 or so with the burner running. Finally the drop out should be in 2 to 2 1/2 minute and the reading between .75 to 6 millivolts typically 1 to 2 millivolts.

rbeck

Very well could be a combustion air problem. When O2 levels drop flames roll out looking for more O2 and snuffs out pilot. Just sayin.