Ultrasonic Flow Meters

Zman

I have been looking for a while at Ultrasonic Flow Meters.

I have an increasing need to be able to answer questions like:

How do you know that the oversized recirc pump is eating our pipes?
Are you sure we can reduce the size of our heating circulators and save energy without sacrificing performance?
Is the filtration rate on our hot tub filter or pool filter correct?
We have been billing the restaurant portion of our business "X" for their hot water use. Does that sound about right?
We would like to know approximately how much heat the different entities on our property are using without installing BTU meters. How do we do that?
Why is this zone under performing?

I already have a bunch of temp humidity and electricity loggers and like to add flow to the mix.

I need a meter that can measure tap water and glycol mixes. The temp range would need to be anything from near freezing to 180 degrees or so. Copper, steel and PVC/Pex compatibility would be ideal. I think 3/4" to 3" is about the pipe size range. It also need it to either be able log quite a few data points or be compatible with pulse or 4-20mv loggers.

I have been giving this one a long look.
https://www.pce-instruments.com/us/?id=58850c6b25817980&_baseurl=/us&action=ShowItem&_list=&_listpos=&_artnr=5841285

Does anyone have any thoughts?

hot_rod

We were fortunate to have Badger Meter near our location in Milwaukee where NA headquarters is. They are very knowledgable, they let us tour their facility and borrow and test various meters.

With their suggestion we went with this doppler meter.

It was $$ and you buy a set of "cuffs" for all the various sizes of pipe that you will be testing.

They have good info and videos at their site.

You want portable, and something that straps on without cutting into the pipe.

https://www.badgermeter.com/search/?keyword=clamp on ultrasonic flow meters

Another critical meter for your area is a gas pressure data logger. Something that would graph and print out gas pressure at the boiler over the course of the week or more. That low intermittent pressure condition from the utility really gives the HVAC tech and troubleshooter fits.

Zman

I started out looking at the badger models. They sure are nice (and expensive).
It turns out the model I was looking at has been branded for a bunch of companies. In will have to look into this further.
https://www.amazon.com/Portable-Digital-Ultrasonic-USF-100-Transducers/dp/B01G139G18/ref=pd_sbs_328_6?_encoding=UTF8&pd_rd_i=B01G139G18&pd_rd_r=4WY5KSYHXX79K86PK0R4&pd_rd_w=63L0j&pd_rd_wg=ClErU&psc=1&refRID=4WY5KSYHXX79K86PK0R4


The gas pressure logger will be on my list at some point. Pressure drops are common in outlying areas. I did run into a pressure issue recently caused by that stinky oil that forms in the lines causing a trap in a line. Had to throw away those gloves...

EBEBRATT-Ed

I don't own one but what I was told several years ago from a Balancer was that they won't work with glycol and any air (bubbles) in the pipe will cause problems.

Maybe these issues have been solved.

Zman

I went though the manual and noticed there was no setting for glycol. I thought it was strange because there was for diesel, alcohol and all sorts of other liquids.

ratio

http://forum.heatinghelp.com/discussion/comment/1458227/#Comment_1458227. I'm not sure about compatability with plastic pipe, as I understand it the ultrasonics are transmitted through the pipe wall, something as soft as PVC or PEX might not have the necessary conductivity. Also, most/all the cheap ones I've looked at did not include transducers rated for more that 70-80* C—I'd like more headroom than that.

hot_rod

EBEBRATT-Ed said:

I don't own one but what I was told several years ago from a Balancer was that they won't work with glycol and any air (bubbles) in the pipe will cause problems.

Maybe these issues have been solved.

That is why we went with the Doppler style, it reads aerated and dirty fluid best. We do testing on air and dirt removal devices, pumping air and dirt into the fluid stream, so we need the best accuracy.

That connection to the pipe is critical, we smear acoustic transfer grease under the saddles when clamping them down.

hot_rod

Zman said:

I went though the manual and noticed there was no setting for glycol. I thought it was strange because there was for diesel, alcohol and all sorts of other liquids.

Glycols are really just derived from cracking petroleum, it is sort of a propane product. Although it can be made from plant stock, bio glycols.

If it works on oils and propane, you should be fine, never hurts to ask the manufacturer.

JohnNY

I'm reviving this thread. I want my own clamp on flow meter in the worst way. Has time/technology made these things any cheaper yet?

EBEBRATT-Ed

Maybe technology has improved. We had a large job a few years back where we had a flow issue. (The engineer you blamed us for the problem turned out he undersized the pumps)

Anyhow we called a balancer in to help find the flow issues and he whipped out this big super expensive ultrasonic flow meter.

Said it wouldn't work on glycol (which we had) and is inaccurate with bubbles in the system which we had as the system had just been filled

I wasn't impressed

Zman

I should have followed up on this one. I did end up buying the meter I was asking about. I spent hours reading the manual and then proudly went out to try it. I installed it on nice straight sections of domestic pipe ranging from 3/4" to 3" copper. When I compared my results to the water meter reading I found that they were 20%-30% off in both directions. I know the technology works because it is widely used in industrial applications. I do hope there is a product that works well in the field. I sure have not found it yet.

EBEBRATT-Ed

The balancer we hired swore it would work. But it didn't, way off. might as well hold your fingers up and see how many fingers it takes to cover the pipe....useless

JohnNY

Zman said:

I do hope there is a product that works well in the field. I sure have not found it yet.

Well this is good information that probably just saved me $3,000 or more. So thank you for that.
Also, @Zman, I love your Einstein quote. In our trade, those are words to live by. I've tried to only speak to others about things that I can explain simply. If I can't, then I get better informed, and then I'll revisit the topic.
Just saying.

nicholas bonham-carter

i wish our politicians and other influencers would follow John’s example.—NBC 

hot_rod

I have played around a bit in our lab with an ultrasonic meter, they can work great and are lab quality accurate.
But any air at all tends to make them go crazy. The cuffs need to be a perfect fit and some transfer grease helps get a perfect contact.

There are a number of flow reading technologies, all with pros and cons. They measure sewage flow with accurate flow meters so s--- happens

Maybe do some weekly rentals to find one that works best, many online stores rent them.

EBEBRATT-Ed

The problem is how do you know if what the ultrasonic is reading is correct? Any test instrument you can't trust is useless