Seeking advice, new to boilers, boiler broke over winter

triode

Recently purchased a home (have not yet moved in). It has a 52 year old Burnham Series 4, 200,000 BTU boiler. It was steam, and someone (long ago) converted it to water. It was working when we purchased the house, but inspector said "its old, replace it". I called a few people who really wanted to push me to replace it outright, but were quoting me crazy money quotes to replace it.

Just for notes, it is a two story house, four radiators upstairs, six radiators downstairs, boiler in the basement. It used to vent out the chimney, but that failed and they are now venting with a blower out the basement window.

Long story short, I have had two boiler techs come by and say things like "well, the cast iron boiler itself looks ok, but a lot of these other things were not maintained" or "gee the boiler can't be 52 years old, it looks good, maybe just clean it and let it run". Shortly after this, the gas valve failed, during some of our coldest times, so I drained the boiler as much as I could (boiler drain was locked up, in fact the water feed valve and auto-fill and bypass valves were locked up).

Here is the situation now: boiler mostly drained. Gas valve is bad. I was going to replace the valve with a universal pilot ignition (Honeywell Y8610U-6006/U). I would also need (I am pretty sure) to replace the autofill and back flow preventer (BFP), as well as the bypass valve and main inlet valve. There is a Aquastat on the side of the boiler, no idea if it works. The boiler pressure/temp gauge is also stuck as it did not move from 10psi after I opened the boiler and drained 80 gallons of water out of it, so that would need to be changed. The burners need a really good cleaning, and the manual gas valve is probably 100 years old (would change that too). Would probably add a rollout switch as it (from visual burn marks) had an issue with that in the past due to a broken chimney.

I know none of you can see it, but the boiler outside is in rough shape. Figure it would be approaching $1000 in parts to do what I mentioned above, and although I am handy and an engineer and have done a lot of electrical, I have never done boilers. Should I try to get this Burnham going? The three local heating / boiler places I called for quotes on a replacement boiler want nearly $20,000 to replace, but this seems outrageous. A weil-mclain is like $5,000. The circulation pump seems fine, so not sure why they want $15,000 in labor for something they say they can totally do in less than one full day with two techs. (call me crazy, but $7500 per tech per day is kind of high)

I am attaching a drawing of what I think is the current setup. I am not sure if I would need to change the B&G components: SA 1&1/2, 1AF-1&1/4, ATF12, but I have no idea how to test them. The system was "working" before the valve failure, in that it heated the home nicely, but not sure if it was "correct".

Again, do I spent $1,000, change the valves, auto fill, BFP and gas valve and fill it (would have to read about filling it) and hope for the best, or just call someone and say "take all of my money and then some" and have it replaced?

ethicalpaul

Welcome to NJ! (just guessing)

Show us some pictures. We like pictures!

Based on what you said, and your description of yourself, I would spend the spring learning about cast iron hot water boilers and their controls and get it going.

You will be able to use this knowledge for the next X years living with this boiler (or its eventual replacement), and you can always spend the big money later if you don't like the results of fixing up this old one. Or you can do like I (and several others) did and install your own replacement boiler.

PS: free hint: your expansion tank in your drawing looks like the old kind that they strapped up to the floor joists that is just a tank with no bladder. Which is fine, but it's probably flooded so drain it. You can't tell by tapping if it's full of water.

triode

Hello,

The house is located in the midwest, actually.

Will grab some pictures next time, all of the pictures I have are just of nameplates.

Yes, the expansion tank is strapped up to the floor joists. It has 18 Gallons, 75lbs working pressure and D-1/86 written on it. I am guessing the drain on it is locked up. It is always amazing to me that most people never exercise a water valve and expect it to work years later. I am still confused about how this tank with no bladder operates (e.g. how does it not fill when you fill the boiler? You must have to shut it off somehow during the fill cycle, or is that what the B&G ATF12 does? It must be, right, otherwise the autofill valve would fill it, or are we just relying on compressed air in the tank for this?)

ethicalpaul

The air inside it has nowhere to go (that's why they put it in the ceiling), so it compresses to equal the pressure of the water in the system.

But after some years, all the air either leaks out or it gets absorbed into the water and so these old tanks are often waterlogged and then they don't provide any compression (because you can't squeeze water very easily)

But anyway, you will learn all kinds of other helpful nuggets of knowledge as you get your boiler operating again and you will not be subject to the whims of market pricing of scarce knowledgeable contractors anymore.

(the expansion tank example is an interesting one—I helped a friend drain hers which solved her leaking pressure relief valve issues after 3 different contractors were there and couldn't figure it out. Then 6 months later she had another plumber there and he was even old like me and told her "there are no expansion tanks that don't have bladders". You can't make this stuff up!!! She now knows more about her boiler than at least 4 different HVAC Plumber guys in her town! This is not a statement on her or my level of awesomeness, but rather a statement on how hard it can be to find knowledgeable contractors especially when it comes to older systems. But if you use the Find A Contractor feature on this site you will increase your odds significantly)

Grallert

"just relying on compressed air in the tank for this". You got it. That's how it works.

hot_rod

Did any of the contractors perform a heat load calc? How many sq ft of home? A 200,000 boiler is quite large.

It is always a tough question when to start new or keep dumping $$ into old boilers and components.

You could do a heat load to at least get a starting point for the project.

How do you generate DHW?

triode

https://forum.heatinghelp.com/discussion/comment/1892741#Comment_1892741

Funny, before I even knew anything about boilers, I know from my other work that when you put in an HVAC, you need to know the load. I asked them, and every contractor had some magic formula.

HVAC guy #1: 200,000 is very large, but just looking at your home i can tell you 150,000 is fine.

HVAC guy #2: The person who speced out this burnham must have know what they were doing.

HVAC guy #3: 200,000?!? Well, it is a large old house, I guess we should put that back in.

The house is about 2200 sq feet. It is drafty. I actually tried a load page I found, but it started going down roads I did not have measurements for (how long is each wall on each side, etc). The ceilings are 10feet high, walls are plaster, ceilings are plaster, windows need work and I am sure leak a lot.

hot_rod

There is no substitute for a load cals. Room by room is ideal to confirm all the emitters match the actual room loads.

Just a WAG with a fairly big load number of 30 btu/sq ft.

30 btu/ft. X 2200= 66,000 btu/hr required.

Your current boiler/ bid, 200,000 boiler at 85%=170,000 output.

How do you feel about these guesstimates?

As you plan on updating the building envelop , the load should continue to go down. As well as fuel use :)

A modulating type boiler is ideal for several reasons;

Efficiency, with outdoor reset, temperature always modulates

Comfort afforded by continuous circ via ODR

Boiler can derate as you continue to upgrade building, if you need 66K now maybe that load drops to 40K after upgrades.

A % of the year you will run in 90% + condensing mode

Combustion air grills can be eliminated

Rebates available in many areas for efficiency upgrades www.dsireusa.org for info on that