Circulator Pump Direction

Weezbo

if you dont have any heat...and you just installed a new circ...flip the thing around...then the water will go the direction of the arrow *~/;) because evidently it wouldnt go when it was pointed in the other direction...so basically you have a 50 50 deal there if you never installed a circ ...

Jim H.

Circulator Pump Direction

Does the direction of flow through a cast iron boiler matter?

On a circa. 1950 cast iron Boiler, the circulator is mounted to the lower boiler water port near the burners and the arrow on the pump is away from the boiler into the insulated and hotter supply piping. It appears that the flow direction was reversed in this system to accomodate the exisiting piping.

I am replacing this boiler. Does the direction of flow matter? In the installation manuals, usually the circulator is shown on the return side with flow going into the lower burner port.

The brochures usually show the lower burner port on the left side of the boiler. Can this normally be easily changed over to the right side?

Ken_40

In the order asked...

1) Yes. It matters a lot!

2) With few excpetions, the top of the boiler is where the supply outlet is. Many, installed the circ. on the return, the lower of the boiler threads, which was "normal." The direction of flow was reversed and is wrong in all but the infamous G.E. boiler line of the 30's through mid-50's.

3)Replace the boiler, the flow must be as the manufacturer states ( as you already suspect).

4) Recheck the diagrams. Most boilers of today show the circulator on the top of the boiler, with the expansion tank tie-in located between the boiler supply outlet and the circulator mount. That relationship is critical in today's boilers and circulator designs.

5) If you're in doubt, buy Holohan's seminal "Pumping Away" book. Buy the book BEFORE you attmpt the install. When opening the book, and if listening carefully, you can hear the hydronic gods sing, "uMMMMMMMMM..." (;-o)