Piping Hot Water Loop off Steam Boiler

Adam_13

Hi all, we're installing a replacement steam boiler where the owner wants a new hot water zone for a small in-law apartment. We've done the numbers on the btu draw and are within the 1/3 capacity limit recommended by Dan. I have two questions on the piping.



1.  Can the hot water loop (bypass and all, as diagrammed in We've Got Steam Heat) be in copper? If not, where do we transition from steel?



2. Where does the aquastat go?



Any help is greatly appreciated. Thanks for your time, -Adam

JStar

...

You can run the loop in copper. You should use brass or dielectric fittings to separate them from the steel. The aquastat should go on the supply side of the loop before the bypass. It's main job is to stop the boiler from steaming, so it should only be sensing the boiler temperature and not any return/bypass water.

Steamhead

Here's a pic

of one way to pipe the aquastat. This is the White-Rodgers one with the long probe, and it reaches all the way into the boiler section. The bypass and circ are around back of the boiler. Oh, and the circ should be a bronze 3-piece like a B&G 100AB or Taco 110B so the boiler water won't eat it up. 

Adam_13

Thanks guys

for your responses and tips. I'll look into finding a long probe aquastat and make sure to use one of the circulators suggested. 

turbobike

similar setup w/a problem

I have a hot water loop off my steam boiler and I am regularly replacing the cartridge and ocassionally the circulator motor itself. I have a Taco 006BC4 unit, and I normally replace the cartridge at least once per heating season(sometimes twice). The cartridge binds up and won't turn. When I drain system to replace the cartridge, the water is quite rusty .

I know steaming a boiler adds air to the system as does opening the system to replace the cartridge, but both seem unavoidable under the present circumstances.

Your article mentions using a TACO 110 circulator to avoid the pump being "eaten up".

Do you think this would resolve my problem ?

I am running a Weil-Mclain oil fed boiler about 10-15 yrs old. Should it be "skimmed" periodically to reduce the junk in there?

Steamhead

Yes it would

since this type of circulator is lubricated by oil, instead of the system water. 



But that rusty water should be flushed out too. Dirty water makes lousy steam.