Gravity system below heat source

Arthur

Got a job coming up were the client wants the system piped gravity as he does not want to depend on power to run a pump. Got ideas of going off grid.

The system used old CI rads mounted on walls below the heat source. We can have to  run the return pipe back up inside the wall from the rads because of the concrete floor and doorways are between the rads.

He is using a wood stove with a 20Kw wetback which will have to be on a indirect system.

I intend to drop a loop in the return pipe from the bottom of the rad before it goes back up again. And because it's a uncontrolled heat source I will be using copper piping. 1" headers with 3/4" drppers. to the rads.

Any advise on making sure it's going to work?

Thanks.

Big Ed_4

Gravity

An old gravity system was the most complicated system that was installed .… Every pipe size and hight of riser was calculated to assure a proper balance of heat distribution ...



Now what you are saying is the radiation is below the boiler ? I don't think it would work .. What is moving the water against gravity ???

Mike Kusiak_2

Don't think it will work

The heat source has to be at the lowest point in the system for gravity flow. The heated water is "lighter" than cold water. The whole idea of a gravity system is for the less dense hot water to flow upward to the radiators where it is cooled and then the cooler, more dense return water drops beck to the boiler because of the difference in density. Whats going to make the lighter hot water from the boiler want to go down to the cooler radiators below?

Charlie from wmass

need bigger pipes

1" is way to small and as said before gravity is used and it does not work that way. Time to dig a hole in the basement and install boiler in a pit.