gravity hot water conversion

Brian Maffioli_2

I have been reading and trying to educate myself about a gravity hot water system conversion I just looked at today. I am pretty confident about the whole process except for the reducing of the near boiler piping.

What constitutes near boiler piping? There is what appears to be a 3 inch supply main that travels at least 10-15 feet from the boiler with some parts hiding inside of a soffit of a finished basement.

How near is near boiler piping?

Thanks in advance.

Mark Eatherton

That piping which is connected TO the boiler...

is NEAR boiler piping.



Rule of thumb, 1/2 of that piping, then one pipe size less, so in your case, 1-1/4" new near boiler piping.



ME

Brian Maffioli_2

gravity

Hi Mark,

So if I understand this right, if my 3 inch supply main starts at the boiler and continues 10-15 feet away from the boiler, that whole length is considered "near boiler piping?"

Mark Eatherton

Correct

If you wanted to break the pipe back to the first branch, and install a 3" X 1-1/4" bushing, that would be acceptable.



ME

TonyS

Gravity conversion

Remember, your gravity system is a 2 pipe direct return. When you add a pump the water is going to take the path of least resistance. Reverse the returns or add TRV,s to retain some balance in the system.