No aquastat tap for SGO boiler if not using tankless coil

Peteys

I’m looking at the new Weil McLain, SGO -4 steam boiler and don’t see a tap for an aquastat if not using the tankless coil.  Would you just use  “E2” tapping?  Not sure why boiler wouldn’t come with an aquastat or specific tapping as most boilers wouldn’t be run cold start.

Where do you put the aquastat if not using a tankless coil on a new SGO-4 boiler to control the boiler water temperature for an indirect water heater and small run of 25 feet of baseboard?

nde

Who manages your current boiler? Having an installer that knows what they are doing especially with steam is essential. I think traditionally the tapping for the loop are lower should be in manual. Ok think that is u1 at back of boiler for loop u2 left of tankless area for indirect. Page 15/16 of manual. Should work if you find good installer.

Print out the manual and make sure the installer pipes everything correctly as setup in that manual. This is very important and the most critical part of your new boiler install.

Peteys

Also,  what tapping would you supply and return to, off boiler, to a 25 foot loop of baseboard heat off of boiler?

EBEBRATT-Ed

@Peteys

The 1" U1 tapping can be used for the indirect and for the baseboard. 25 feet of baseboard only needs 1.3 gpm. The aquastat goes in U2. The blank tankless coil cover plate may have a tapping as well. You could also use B1 as the indirect and baseboard return. The indirect has it's own aqustat. For the baseboard use a strap on aquastat if you have to

Peteys

Thank you Ed

Kind of strange that they don’t provide an aquastat with these new boilers if you’re not using a tankless coil. So I guess all new Weil McLain steam boilers are cold start without a tankless heater?

You would think they would at least have a separate tapping for an aquastat if you weren’t using a tankless coil.  This way you wouldn’t have to remove the boiler cover over the tankless coil to get to an aquastat tapping to control water temperature for an indirect or separate baseboard zone.

The U2 tapping is only on the SGO 6-9 boilers

HVACNUT

All steam boilers are cold start unless the boiler is needed for something other than steam. 
Check with WM but the SGO-4 should come with a coil plate with a 3/4 tap for an aquastat well in the U3 location. 
And there should be a knockout in the jacket for coil plate access.
Maybe you're only looking at the package boiler? They might be cast differently than the knock down. For instance, a WGO-3 knock down has a 1.5" rear tap as an alternate return, but the WGO package does not have it.
Is the going to be DIY?

Peteys

I never knew that all steam boilers were cold start.  I used to be in the business many years ago so I kind of know what I’m doing but I’m not a full-time pro like most of you guys. Takes me a lot longer as I don’t do it every day.  just planning right now as the boiler is 32 years old.  It’s amazing it’s lasted that long.  

EdTheHeaterMan

There are some 80 year old Weil McLain boilers in basements all over the north east that started out as coal burners. That boiler may last another 20 years, you never know! There's going to be some mud at the bottom of that boiler. You will want to flush that out when you take it apart. At that time you might want to think about running the return to the bottom of the boiler B2 return tapping with a tee or attached a tee to the drain valve and return ti there. This will keep the bottom water moving a little faster. Also place a Y-strainer in the new return for easy maintenance.

Peteys

Thanks Ed,  much appreciated!!