adding return pipe to a monoflo system

Unknown

Not sure I understand,,,<BR>
Are you trying to run another zone from a m/f circuit, or from the m/f main?<BR>Could get into problems here, be careful!<BR><BR>Dave

Michael_17

adding return pipe to a monoflo system

Would like to know if you can keep the incoming monoflo tee to the radiator riser for the main supply while installing a dedicated return? Am converting a single pipe system to a two pipe however, trying to save the folks some money. I've done this before by removing everything except the radiators and used all copper with standard tee's. Thanks for any insight. Michael

Michael_17

I am converting a single pipe hot water system into a two pipe system. This system has monoflo tees. My question is can I keep the supply monoflo tee and pipe the return side of the radiators to a dedicated return pipe? It would seem to me that the monoflo tees might restrict the supply flow to the other radiators. I am trying to avoid replacing all the tees in the system.

Big Ed_4

Word of Advice

The money you save the home owner will come from your pocket .

I can not see the savings converting a monoflo to a parallel system. Why ? Tell me more ...

kevink1955

I attempted to split a Monoflow in to 2 zones once and had major problems. When zone 1 called for heat the water had to flow past some zone 2 monoflow tees, they scoped up some water that flowed into the zone 2 radiator then out of the radiator into my new zone 2 return pipe where it then flowed up the return of another zone 2 radiator and out it,s inlet back to the Monoflow supply.

The first zone 2 radiator was close to the boiler outlet, the second zone 2 radiator was closer to the circulator on the return side of the boiler. The water took the path of least restance thru the zone 2 radiators rather than flow thru 6 Monoflow tees in between.

If you are staying with a single zone, I agree with the previous post. Why bother, Monoflow works great as designed.

Big Ed_4

Hydronic Systems

Water moves though a hydronic system two ways. A drop in pressure and gravity. Gravity is the weaker of the two and works off that cold water is more dense then hot water. Mass pulls to mass. Larger the mass greater the pull.

The greater force in the system is pressure drop . The circulator creates a pressure drop across a zone . It really is not a pump but more like the motor on a ferris wheel.

Monoflo uses these forces to move water to the radiation. The circulator creates a drop of pressure across the main The system uses a vanturi tee on the "return" riser to redirect the pressure drop across the radiation loop. One on the return for up feed radiation , two on down feed radiation. You need two to redirect more pressure drop to counter the force if gravity.

Follow the flow arrow marking on the tee. Or the inside cup of the return riser tee is facing down stream if flow. Supply faces up stream.
The water flowing through the hole in the tee creates a pressure drop on the riser by creating a venturi.

Three added facts ; The larger the distance between the tees the larger the pressure drop. You need to space the tees atleast the Lenght of the radiation. That's why just adding base board to exsistant radiator or convector system does not work as good.Also common sence. Every loop needs to purge air. The only way is the bleeder. On a radiation loop a bubble must always rise in the risers and radiation element to that bleeder !

Never restrict a flow on A monoflo system . That flow is needed to tranfer the pressure drop and BTU's. Drop it below the largest designed load and it will not work on the coldest days of the year.

A parallel system ; Best way to look at this system , think of a ladder and the rungs as the radiation. And the side rails and the supply and return This works off the same forces.

Big Ed_4

continue

Side rails are the supply and return. If you supply and return both from the top and bottom. The pressure drops off the further you go out on the ladder. What you do is reverse the return to equalize the pressure drop , the supply feeds let say the bottom and returns from the top. Now all paths are at equal lenghts.

Oh.... To zone a monoflo system you need to supply each loop with a supply and return of equal size.

Got to go Mrs Murphy is on the phone again.....

Good luck never stop learning or you will be dead.