Circulator Discussion

drooplug

I know I need to place the circulator as low in the system as possible and to pump away from the PONPC. However, does the circulator placement matter concerning brazed plate heat exchangers and buffers tanks?

Jamie Hall

Remember that the objective of the exercise is to ensure that under all possible operating conditions there is adequate pressure at the inlet to the pump. The most reliable way to do that is to ensure that the PONPC -- typically an expansion tank -- ls located close to but not right at the pump inlet, with minimal pipe fittings (e.g. elbows) in between. Beyond that..

EBEBRATT-Ed

The pump does not have to be at the lowest point. It is a closed loop and makes no difference. Pump away from the expansion tank. The water make up should be at or near the expansion tank. Try and put any restrictions (brazed plate etc) on the pump discharge

drooplug

Thank's for the input.

Siegenthaler recommends keeping it low in the system to avoid cavitation. My circulator will be in the basement, so I will balance keeping it low and having a functional layout.

drooplug

What about in situations where there is more than one circulator in the system? Such as using a circulator to pump zones.

Gordy

Having a sketch of the piping, and components would be helpful.

hot_rod

I think you have posted before with the open system OWF?
In open systems the circulator needs to be as low as possible as the water level above the circulator is the only "head" it sees.

Put any devices downstream of the circulator. At high operating temperatures you are riding a fine line for cavitation issues with high head circulators especially. Any flow restrictions on the suction side will further encourage cavitation in the circulator.

drooplug

I do not have an open system. I had posted in the Heat Pump section.

I am currently working on a piping diagram.