Pad for boiler

Jersey2

So the Slantfin was delivered today. It is tiny and seems cheap lol. I guess all modern boilers are made with lightweight metal. The front part of one foot is bent, I will post a picture. Anyway, the installer wanted to have it on my basement floor, but I want to have it off the floor because I have a damp basement that sometimes gets excess moisture, and any metal on the floor rusts. The installer said I can get patio pavers to put it on, and I found this 23X23X1.8" step stone. Do you think it would work good for a pad, or will it crumble? I wonder what the green stuff is in pic 3.
https://homedepot.com/p/Oldcastle-23-3-in-x-23-3-in-x-1-8-in-Grey-Concrete-Step-Stone-12052900/312182701?MERCH=REC-_-pip_alternatives-_-312965133-_-312182701-_-N&

DJD775

I don't see why that wouldn't work. Typical installations in my area are usually on 2" or 4" solid concrete blocks.

leonz

The green stuff is residue from the casting sand that was not cleaned off and needs to be removed before the plumbing/circulator is installed.

You need to have the boiler off the floor because of the electrical conduit box on the side of the boiler.
4 inch solid concrete half blocks are good for this application.

The higher the boiler is off the floor the safer the boiler is and the less likely you may have a boiler that could be water damaged from a basement flooding.

Is that the old boiler on the concrete pad to the right in the image?? If it is going to be removed you could install the new one there.

Jersey2

Oh, okay about the green stuff. At first I thought it was copper corrosion, but it looked more like thick paint. I was thinking it might be a mark indicating that the part passed. I will try and clean it off, I imagine it might start corroding once water contacts it. Yes, that is the old pad. He won't use the old pad because he said it doesn't fit the boiler, and he is going to put the boiler in the corner. So he plans to remove the existing pad. On the positive side it would make more room in the basement. Another reason, which I am guessing, is that the current hole in the chimney would be too low for the boiler if it was on the existing pedestal. It looks like the current hole just makes the height with the boiler on the ground.

Jersey2

A picture showing the stack compared to the hole in the chimney. To me if it is raised even 4 inches, the current hole would be too low. Can see where the new gas pipe is in the back so he has committed the boiler to be back in the corner. The down side is it will be harder to get to the chimney clean out door, and to the drain on the left side of the new boiler.

mattmia2

Post some pictures of that old boiler with the front cover off before it gets torn apart

Jersey2

The hvac guys were like "wow look at that" when they went in the boiler room :-) So I went and got 4" solid cinder blocks for pads. 4" isn't all that high a rise, I can't imagine it being a problem. I will ask them to put the water heater on a 4" pad too.

EBEBRATT-Ed

The vertical vent pipe on the boiler with the draft diverter cannot be shortened so factor that in.

Unless you make a new hole in the chimney. The horizontal run from the boiler should pitch up slightly and never pitch down

JimP

Years ago a boiler manufacturer engineer told me that it's not a good idea to just raise a boiler off the floor on blocks. The amount of air space under the boiler is part of the combustion design. If you want to raise the boiler it's a good idea to have some sort of pan under it so that the air space remains the same. I find that a steel plate works well. I've also used Durrock type board but find that it breaks down a bit over time from heat if the boiler runs a lot.

mattmia2

JimP said:

Years ago a boiler manufacturer engineer told me that it's not a good idea to just raise a boiler off the floor on blocks. The amount of air space under the boiler is part of the combustion design. If you want to raise the boiler it's a good idea to have some sort of pan under it so that the air space remains the same. I find that a steel plate works well. I've also used Durrock type board but find that it breaks down a bit over time from heat if the boiler runs a lot.

You can always use solid core blocks and enough to fill the whole area. I even set them in mortar for my water heater so I could set them level so the water heater would stand level without shimming.

JUGHNE

Sometimes it is permitted to place the motorized damper in the horizontal pipe.
If so then a 90 on top of the draft hood and then horizontal damper might get the run lower so as to use 2 or 4" blocks under.

I believe that these atmospheric are designed with a solid floor under the burners.
Some boilers actually have a lower burner pan to confine that air space.

But a block on each corner could possibly mess up the air mixture around the burner.

NoelAnderson

The Slant Fin is a not a cheaply made boiler. I think model selection is the wrong one for your application. Is there any way you can return that model to your supplier and ask for Slant Fin's Sentry model instead. It has a built in draft diverter for lower chimneys.

DJD775

Great work! That's one nice looking boiler/water heater pad.

Jamie Hall

Not really related to this thread, since this is hot water, but... if you are replacing a steamer, and the old one is working quietly, remember to use whatever height pad or blocking may be needed to match the water lines. It can make quite a difference...

Jersey2

If they place the 16" x 8" solid blocks such that each one overlaps by 8", it makes a 24" square with an 8" square of space in the middle. I can't imagine an 8" empty square in the middle under the built in pan would make any difference. There would be a floor under the front, 16" one piece and the 8" on the end of the 16" block. And wow that is a fancy base you made! I do think they will have to make a new hole into the chimney. It is a Slantfin Sentry. I felt like it was cheap from seeing how easy the sheet metal bends, case in point the bent front part of the leg. I do like that the front panel comes off easy without tools and access to the burners is right there. I think it will work good. I have to wait for a pressure inspection and then for a meter. I guess that will take 4 or 5 weeks.

Jersey2

Oops it's a Sentinel not Sentry.

Jersey2

All done! That was a long process, from getting the gas line to the install. For the pad I ended up getting the 24X24 cement blocks, and the installer stacked them for the boiler and used the existing pad for the water tank, the water tank is fat. I think he did a good job, I am happy with it. It's a very simple system.

EBEBRATT-Ed

IT looks good, but i would have rather seen the circ pump on the supply. Probably not an issue

EdTheHeaterMan

I would put my name on that work!

hot_rod

Very nice work.
I'd send the installer a copy of Pumping Away
Is that 193F on the display?

JimP

That looks like a nice installation. Is there a wire between the cold and hot water pipes at the top of the water heater? If so, what’s the purpose of that.

JimP

By the way…Doesn’t it look like they’re pumping away?

Jersey2

I assume the wire is for grounding purposes. Yes 193F. After it stops burning at 180 HL, the temperature keeps climbing. If the call for hot water stops before 180, the boiler stops at a lower temperature. The circulator pumps into the boiler so yes, it is on the return. Idk what is an advantage of pumping at supply versus the return. I like that the water tank stays hot for a long time, it is well insulated. Thus far I love it. It will be interesting to see how much fuel/money it will use in a year.

Jersey2

Figured I would share the savings in fuel after converting to gas, since I've gone an entire year. If I would have purchased oil, I would have gotten 600 gallons at 3.99, which would have been $2,394.00. Cost of gas for the year was $633.15. So I saved a lot! Granted it was a mild winter and I might have had a lot of that 600 gallons of oil left.