Very very old furnace with cracks (Severn Boiler)

Charlotte88

I have a very very old furnace that was probably intended in its first years of life to work with coal. (That's what the previous owner told me) It was later on converted to gas. I noticed that there is cracks appearing on the sides of the furnace and I can see the fire inside burning!! I was wondering if anyone knew of to repair those? Is there any type of cement that I could use to fill in those cracks?

Thanks

STEVEusaPA

It’s done. Stop using it before you burn down your house or die from CO poisoning.

mattmia2

Isn't there a refractory lining that should be on the other side of that which appears to have collapsed?

delta T

For the money you would put into this to repair it properly, you could install a new boiler that would save you significant amounts of money on energy savings alone.

HVACNUT

> @mattmia2 said:
> Isn't there a refractory lining that should be on the other side of that which appears to have collapsed?

Those crack are above the chamber. There might be a kaowool board or bathtub style chamber in there but that's besides the point.

Agree, it's (way past) time to replace. Forget efficiency. Safety alone makes it a no brainer. Even without the cracks.

The American Standard Arco Leader (same design) boiler was one tough cookie. Oil conversions I've serviced probably thousands. With the Jimi burner. Thanks @STEVEusaPa

Ok old guys. Dominion Radiator. Did Standard drop them to go with American? Did American absorb Dominion?
Who knew I could be sitting on a Dominion Standard throne?
No asbestos or boiler jacket either. Hmm.

ChrisJ

Doesn't look like cracks to me, looks like the seams between the sections. No? @Steamhead

ratio

It's lived a good life. Time to get it replaced by a skilled contractor—try here.

EBEBRATT-Ed

@Charlotte88

I am all for saving old equipment but it's time for that boiler to go. It is potentially unsafe. The combustion chamber is gone and it needs sealing between the sections.

A new one properly sized will save money on fuel.

Find the right contractor. Not the cheapest price

ChrisJ

EBEBRATT-Ed said:

@Charlotte88

I am all for saving old equipment but it's time for that boiler to go. It is potentially unsafe. The combustion chamber is gone and it needs sealing between the sections.

A new one properly sized will save money on fuel.

Find the right contractor. Not the cheapest price

How do they go about that?

Steamhead

ChrisJ said:

Doesn't look like cracks to me, looks like the seams between the sections. No? @Steamhead

Correct. Severn boilers had jackets over the sections, so ordinarily we wouldn't see the sections. This one has had the jacket removed, probably because it had asbestos insulation underneath. So it's losing a lot of heat to the basement that should be going to the radiators.

On that basis, and the fact that there probably aren't any baffles to slow down the flue gases, I'd plan to replace it at the end of this heating season.

@Charlotte88 , where are you located?

mattmia2

Steamhead said:

Correct. Severn boilers had jackets over the sections, so ordinarily we wouldn't see the sections. This one has had the jacket removed, probably because it had asbestos insulation underneath. So it's losing a lot of heat to the basement that should be going to the radiators.

This makes me wonder how often this happens and no one knows about it because it is under the jacket.

Steamhead

Normally, the firing zone in this type of boiler is under a slight negative draft, so these leaks would result in higher than normal excess air measurements when we do a combustion test.

Charlotte88

Steamhead said:

ChrisJ said:

Doesn't look like cracks to me, looks like the seams between the sections. No? @Steamhead

Correct. Severn boilers had jackets over the sections, so ordinarily we wouldn't see the sections. This one has had the jacket removed, probably because it had asbestos insulation underneath. So it's losing a lot of heat to the basement that should be going to the radiators.

On that basis, and the fact that there probably aren't any baffles to slow down the flue gases, I'd plan to replace it at the end of this heating season.

@Charlotte88 , where are you located?

I'm located in Quebec Canada.
With all the answers you guys provided I think the only thing to do is replace it! I'm kinda stressed out to wait for the end of the heating season to replace it though. Can you replace it in winter?
What kind of boiler do you recommend? I'd like an indestructible kind!

Thanks

HVACNUT

There are many boiler options. Atmospheric, cast iron 3 pass with a gas power burner, mod con.
Looks like two zones. What type of emmiters? What are your domestic hot water needs?
Click on the "Find a contractor in your area" link at the top of the page. Quebec though...

IMO, mod cons are far from indestructible. Of course anything can break, but a mod con has many more parts, can be costly to repair, and parts availability is sometimes not good.

ratio

You're one up on most replacements we see here though—you're asking questions before the replacement instead of after!

pecmsg

The winter is slowly ending. Start getting estimates.
The first and most important thing is choosing the installing contractor wisely!!! DO NOT shop by price.
A heat Load / Loss calculation MUST be done. Ask the perspective contractors how they'll size the replacement, The only proper answer is by a Manual "J" Calculation.
TACO has a sizing chart that you can do too check what the contractor "Claims" is the proper size.

STEVEusaPA

Isn't it always winter in Quebec? I heard that if summer falls on a weekend they BBQ.
Of course I'm joking, we had a wonderful time touring Canada, with Quebec City and staying at the Chateau Frontenac one of the highlights.
Most important is a properly sized boiler, and the installing contractor. Try to get some local recommendations.

mattmia2

Like others said, the first part is for the contractor to do a heat loss calculation for the house, then survey your heat emitters to figure out what sort of water temperature the system needs to use to match the heat output to heat loss.

The water temp will tell them if it can run temperatures where a modulating/condensing boiler will be efficient or if an atmospheric boiler will give a similar efficiency.

Unless the chimney has already been lined it most likely need a liner to be able to draft properly with a modern atmospheric boiler and with the existing water heater without the old boiler heating it. The old boiler wastes a lot more heat than modern boilers and the chimney likely won't draft properly with the cooler exhaust temps of modern equipment. A modulating/condensing boiler with an indirect water heater to produce domestic hot water from the boiler water would vent through PVC or other low temp piping through a sidewall and allow you to abandon the chimney.

bburd

I had one of those boilers, from 1947, which was still going strong when I sold the house in 1998. They are nearly indestructible. The original oil burner had been replaced by the previous owner with a modern Beckett AF.

The sheet metal jacket had air cell asbestos insulation. There was a factory baffle at the top of the firebox, made of fire clay. I added a few bricks in the flueways as additional baffles, which increased the efficiency to over 80%, and replaced a broken fire brick in the combustion chamber—which I think was original.

Those “cracks” are just the joints between the cast-iron sections of the boiler. They would have been sealed with furnace cement or other sealant at the time of installation. You could apply some furnace cement to seal them now; but since they are letting some excess air in over the fire, the burner air adjustment should be rechecked afterwards by a competent tech with combustion test instruments.

Since the boiler should run with a slight negative draft over the fire, no combustion gases should escape from the cracks under normal operating conditions. However, I hope you have a carbon monoxide detector in the house.

As others have pointed out, that is a relatively low efficiency, high mass boiler originally designed to burn coal. Without the insulating jacket, it is losing a lot of heat into your basement. You should save a lot of fuel when you replace it.