how to detect if pump running?

Chuckles_2

Our new installation has new Grundfos pumps that are very quiet. Vibration isn't a good way to sense if they are running, because the pipes carry vibrations from other pumps.

The contractor used what looked like a small compass---he held one up to the pump and it wobbled madly. This made sense to me, but I can't reproduce it---my compass won't do it.

Is there a specific type of compass, or a trick to this method?

Mark Eatherton1

Grundfos...

makes a device specifically made for checking their pumps.

I also use the quick closing trick. If you have a ball valve down stream of the pump, and you close it quickly, if there is flow, you will hear a hydraulic WHOOSHhh.

Another method is to take a small torch and hold its' flame against the pipe served by the circulator. Hold it for 10 seconds, take it off and wait ten seconds. If the pipe is cool (relatively so) there IS flow. If its hotter than hell, there is NO flow. (AKA the oohhh AHHH test)

ME

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

ScottMP

Another trick

Is to use a screwdriver. Put it to your ear and then on the circulator. Its like to old glass on the wall trick.

Scott

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Don Walsh

another idea

Is the intent to find out if the pump is running or pumping? To find out if it is running, try using an amprobe and check for current draw.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Tom Meyer

Checking for rotation

Mark's right. There are tools out there to check for motor rotation. Bell & Gossett makes one too.

I sorta like Scott's throwback method. Makes you wonder how safe the people in the hotel room next door are! 8-)

Tom Meyer
Senior Designer/Trainer
Precision Hydronics Corp
www.precisionhydronics.com

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Mark Eatherton1

CAUTION...

The wet rotor pumps I've dealt with draw the same amperage under normal load as they do with locked rotors...

ME

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Kal Row

the little magnetic indicator that grundfoss

was giving out doesnt work very well - i too use the ball valve vooosh method

hr

I use the spinners

all the time. I find they work great on certain brands of pump.

Place an order with Able Distributors in Chicago to get one. Or Grundfos.

hot rod

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Plumbob

thanks!

Thanks for the leads, everyone! Able won't sell me anything since I am a homeowner (the lowest of the low), but I'll try to get a similar device elsewhere.

Measuring current is possible but hardly convenient; I don't want to open up the box and disconnect leads and so forth, just to convince myself that the pump is on.

Tom Meyer

If this is something you're going to check regularly...


You could think about putting in a flowmeter (or having one of the wetheads do it for you).

Tom Meyer
Senior Designer/Trainer
Precision Hydronics Corp
www.precisionhydronics.com

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"