Flow Sensor and Pipe Sizing

[Brisk]

Hi. I'm planning to have 1-1/4" pipes for my return and would like to add a flow sensor to the return. The Hydros flow sensor only comes in 1" or 1.5" sizes. If I used the 1.5" flow sensor (1.25" > 1.5" > 1.25" > 1" Loc-line), would that be an issue? Will it decrease the flow rate? Or would it be better to go with the 1" flow sensor (1.25" > 1" > 1" Loc-line)? Thanks.

 

[KrisReef]

I just took my wife out to her Favorite Restaurant, Gulliver's in Irving. Our favorite bar tender was there, the restaurant was packed for Christmas but we got seated immediately, fresh bread, drinks, more drinks, supper and a desert cake & candle and then the long drive home but I'm still not fit for posting on a family site.

What does this usage of greater than (>) mean with all the different sizes along the path? If you can measure the flow along the way to be 2 gallons per/minute the same flow has to be present upstream and downstream of the sensor if it's working properly. My understanding is that they are not terribly accurate, but maybe I'm wrong. What I can't figure out is what the numbers are supposed to mean, so I give up. BUMP!

 

[Coolcasino]

Its always best to not reduce. Even if you reduce at the end its still going to choke the flow. I would go with the 1in. Increasing pipe wont hurt to flow. You also have to take in consideration what pump you are going to use and what is the output size of that pump.

 

[Brisk]

I just took my wife out to her Favorite Restaurant, Gulliver's in Irving. Our favorite bar tender was there, the restaurant was packed for Christmas but we got seated immediately, fresh bread, drinks, more drinks, supper and a desert cake & candle and then the long drive home but I'm still not fit for posting on a family site.

What does this usage of greater than (>) mean with all the different sizes along the path? If you can measure the flow along the way to be 2 gallons per/minute the same flow has to be present upstream and downstream of the sensor if it's working properly. My understanding is that they are not terribly accurate, but maybe I'm wrong. What I can't figure out is what the numbers are supposed to mean, so I give up. BUMP!

Sorry, I could of explained it in more details. The usage of the greater than (>) was to just show the flow through the different pipe sizes. So it would be either 1.25" pipes to 1.5" flow sensor, then back to 1.25" pipes and into 1" loc-line. Or 1.25" pipes to 1" flow sensor that will go into 1" loc-line.

 

[ryanjohn1]

Going to 1 in lock line will increase head pressure. Reducing the amount pump will be able to push.

 

[Brisk]

Its always best to not reduce. Even if you reduce at the end its still going to choke the flow. I would go with the 1in. Increasing pipe wont hurt to flow. You also have to take in consideration what pump you are going to use and what is the output size of that pump.

Thank you for that. I'll be using a Varios-8 that has 1-1/4" output without about 10 ft. of head pressure. My plan was to place the flow sensor near the top of the tank where the bulkhead is at and give about 7" of pipe length before and after the flow sensor. I know the 1" loc-line will restrict flow, but was wondering if I went with the 1.5" flow sensor with 7" of 1.5" pipes before/after it, if it will be too big that it will impede flow. Or if I went with the 1" flow sensor and 5" of 1" pipes before/after it, would that restrict the flow more?

 

[Coolcasino]

Thank you for that. I'll be using a Varios-8 that has 1-1/4" output without about 10 ft. of head pressure. My plan was to place the flow sensor near the top of the tank where the bulkhead is at and give about 7" of pipe length before and after the flow sensor. I know the 1" loc-line will restrict flow, but was wondering if I went with the 1.5" flow sensor with 7" of 1.5" pipes before/after it, if it will be too big that it will impede flow. Or if I went with the 1" flow sensor and 5" of 1" pipes before/after it, would that restrict the flow more?

You will restrict the flow going from 1.1/4 to 1. You will also restrict going 1.5 in and out the 1 flow sensor. It dosent really matter what combo you use... the limiting factor will be the 1in locline at the end. The combo that will give you the most flow is using the biggest size pipe and fittings. 1.5 sensor with 7" 1.5 pipe will give you the most flow.

 

[KrisReef]

I think that got covered well enough! :cool:

You can easily use a bucket test to check your sensors measurement and fine tune the pump/flow once everything is set up.

 

[DCR]

The 1-1/2" flow meter is going to give you lower overall system pressure drop at a given flow rate. I would go with that. The friction loss in some of these meters like the Neptune paddle wheels is significant.