How do you measure flow rate at home?

Do you set up the loop with one end in a bath tub. And see how long it takes to pump the 100 L out of the tub though the loop and down the sink?

Or do you guys use a flow rate meter, and if you do which one links plz.

I just want to see what elbows, and NB water bocks do to the flow rate etc etc.

Mycobacteria said:

Do you set up the loop with one end in a bath tub. And see how long it takes to pump the 100 L out of the tub though the loop and down the sink?

Or do you guys use a flow rate meter, and if you do which one links plz.

I just want to see what elbows, and NB water bocks do to the flow rate etc etc.

Click to expand...

You've asked the $1 million dollar question. There is to my knowledge no inexpensive, out of the box flow rate meter for 1/2" tubing that is not restrictive in and of itself. This is why Martinm's flowrate calculator on XS is such a big hit.

Pumping water and timing the end result is really the only way that I know of. I don't think however you have to pump 100L to get an idea though. I have used a 5 gallon bucket before and just ran the test a few times and it gave me a reliable idea. I used an empty gallon jug to dump 4 gallons into the bucket, market the water level with a sharpie, and then timed how long it took to fill the bucket up to the line. I took another bucket and put a barb into the bottom and sealed it and used that for the pump intake, placing the intake bucket higher than the pump so that it would feed.

When we measure flow rate in class we just fill up a 100ml beaker (easy sums) and time it accuratly. And repeat.

You dont need the sharpie its not as accurate.
I dont want it to run dry so Im thinking 100 L in the bath tub. Then I put the outlet in a bucket and place it on an electronic scale.
1 L of water = 1 Kg
1 Hr later recored the total weight.
Do the mods press the Tare button and keep on recording data.
(We only asume evaporation in the bucket is minimal and its constant for all mods I do)

Another way is to measure the pressure drop across the pump. How I did this was to have a tee on both sides of the pump and then run a long (10'+) loop of tubing from tee to tee. you fill it up such that the hights of water are the same. as the pump runs it will make high pressure on one side - high water level. And a low level on the low pressure side. Essentially this is a manometer. Sorry they're old pics but I hope you get the idea. In this case I had like 4 foot of pressure differential. 33 ft of water equals 14.7 psi. You can get the flowrate from the pressure drop using as pump curve for the pump.