H2Flow Meter
- Thread starter JPMorgan
- Start date
This flow meter was installed new in early June. Are you advising that it would be a good idea to remove it and clean it to see if the reading improves? Is it enough to just open the valve at the top and let water flush through it?
Sta-Rite DMJ3-172, Self-Priming, Medium Head Centrifugal Pump, D Series, 5 HP, 208-230/460 Volts, 3 Phase, 3 NPT Discharge, 3 Flanged Suction, 262 GPM Max., 140 ft. Max. Head, Bronze Impeller, Cast Iron Body
Sta-Rite D Series Medium Head Self-Priming Centrifugal Pump Built with a rugged construction and heavy duty motor, this fast-priming pump has an easy service design and air volume control tapping. Note: suction flange PKG 73 (sold separately) i
www.pumpproducts.com
Pentair Sta-Rite D Series Medium Head Centrifugal Pumps
Available in high head or medium head series (high-head in separate listing). Feature leak-proof mechanical seals, easy service design, heavy-duty motors, rugged construction.
- May 3, 2007
- 17,741
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
With almost no head loss which is not possible with that plumbing.
I did not see this gauge which is the pump suction:
- May 27, 2021
- 995
- Pool Size
- 17000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
- May 3, 2007
- 17,741
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Actually, I don't think you posted either of these gauge readings which are the two necessary to assess flow rate:
Yeah..... I'm getting the feeling that the company that did this installation are a bunch of bone heads. First, they install the wrong flow meter for our Sch 40 pipe and then to check the low flow reading on the FV-3 flow meter, they install the BW flow meter incorrectly. Geeez!
Even the engineer got things wrong. His specs call for a flow meter to be installed "in a straight length of pipe at a distance of at least 10 pipe diameters downstream (30") and 5 pipe diameters upstream (15") of any source of turbulence..." But then he specifies "install new h2flowmeter between pump and filter". According to the company that makes these, the h2flowmeters do not require this. I believe the pipe distance is only required for installation of the BW flow meters. Wow.... talk about incompetence! These guys get paid good money and don't seem to know what the heck they are doing.
How do you determine head loss? I know it's probably a complicated calculation, but given our plumbing configuration what flow rate is our pump capable of? Any way to determine that from the pics or is it more complicated than that?
- May 3, 2007
- 17,741
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Suction Head Loss (ft) = 1.13 * Supply Suction (in-hg)
Return Head Loss (ft) = 2.31 * Return Pressure (PSI)
Total Head Loss (ft) = Suction Head Loss (ft) + Return Head Loss (ft)
Both should be measured as close to the pump as possible and there are also corrections for the height difference between the gauges but in this case, they are close enough.
Return Head Loss (ft) = 2.31 * Return Pressure (PSI)
Total Head Loss (ft) = Suction Head Loss (ft) + Return Head Loss (ft)
Both should be measured as close to the pump as possible and there are also corrections for the height difference between the gauges but in this case, they are close enough.
Yes.... all pipe but what you see in this picture is 3" pipe. We had a section (about 8') of 2" pipe on the discharge side that was replaced just yesterday with 3" pipe to see if that would increase the flow rate. No luck there.
You should be able to get 180 GPM at 80 feet of head loss.
The suction should not exceed 17 feet (15" Hg), which leaves 63 feet of head loss for the return side, which is 27 psi.
The suction should not exceed 17 feet (15" Hg), which leaves 63 feet of head loss for the return side, which is 27 psi.
- May 3, 2007
- 17,741
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
I see smaller pipe and bushings so not all of it is 3". Measure the OD of each pipe and they will not be the same.
Hee are the photos of those 2 gauges. So.... anything unusual here? Are these the two pressure readings that determine head loss? If so, is it right around 80 feet of head loss? That would mean our pump is capable of 180 gpm, as JamesW indicated, right?
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- May 3, 2007
- 17,741
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Total head loss is about 81' of head which should deliver a flow rate of around 180 GPM. But gauges like that are typically +- 3% of full scale.
So the pump should be able to deliver that 170 gpm flow rate, right? I'm very interested to see what the readings are when we apply the new label to the FV-3 flow meter!
- May 3, 2007
- 17,741
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Yes, it should be more than that although there is some error in the measurement. However, even at the maximum error for both gauges, which is very unlikely, the head loss would be around 86' of head and the flow rate about 170 GPM so it should meet the requirement.
So it is very likely that when your replace the gauge scale, it will read closer to actual.
So it is very likely that when your replace the gauge scale, it will read closer to actual.
The engineering specs for our installation say it is to be installed "between the pump and the filter". Is this wrong? The pool company has to follow the engineering specs, though, right? Should we install another flow meter after the filter, as well? If the specs call for a flowmeter "between the pump and filter" that is the one the inspectors are going to read, right?