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disconnect the meter and check at the meter.
'if ok pressure at meter, it is the old galvy piping
Diagnose water pressure/flow issue
- Thread starter daveg01
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disconnect the meter and check at the meter.
'if ok pressure at meter, it is the old galvy piping
Diehard
In Remembrance
I would say YES!
But OK means flowing pressure not a static(non-flowing) pressure. As you know, you can get the same pressure through a pin hole as you can get through a 3/4" hole, when there is NO FLOW.
I would check before and after the meter. If there is a difference in pressure then I would call the city and ask
for a different meter. If pressure is bad through out the house after that, then he better start thinking about replacing the
piping.
for a different meter. If pressure is bad through out the house after that, then he better start thinking about replacing the
piping.
Diehard
In Remembrance
Exactly!
But must have water running to have pressure differential.
Copper is almost done. Might finish on Monday. We verified that supply from the city is terrible. My meter is not restricting the supply.
Still trying to understand if a pump can pull more water from the city or will I need a tank to get the supply I need. Going to a pluming supply store today to chat with them about their pumps. They are usually really helpful when I have questions.
Still trying to understand if a pump can pull more water from the city or will I need a tank to get the supply I need. Going to a pluming supply store today to chat with them about their pumps. They are usually really helpful when I have questions.
Diehard
In Remembrance
Put a pressure gauge on that outside spigot and run the water full open somewhere in basement(Basement laundry sink) and observe resulting pressure drop, while the water is flowing.
Based on previous comments, sink flow will be about 2 gpm.
Your static pressure was 48 psi. The new residual pressure will allow a a flow vs pressure curve of the available water supply. That 48 psi will likely drop a substantial amount and show what you can expect for pressures at higher flows if a pump is added.
Here's a sample of what would be expected with various flow pressure results. For example, if pressure dropped to 20, 40 or 45 psi while flowing, the available flow at other pressures can be read off the 0 to 9 gpm scale as represented by this graph.
Based on previous comments, sink flow will be about 2 gpm.
Your static pressure was 48 psi. The new residual pressure will allow a a flow vs pressure curve of the available water supply. That 48 psi will likely drop a substantial amount and show what you can expect for pressures at higher flows if a pump is added.
Here's a sample of what would be expected with various flow pressure results. For example, if pressure dropped to 20, 40 or 45 psi while flowing, the available flow at other pressures can be read off the 0 to 9 gpm scale as represented by this graph.
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journeyman
the professional
Get rid of the galvanized
Can't remember if this was asked already but do you have a galvanized or copper main water line coming into
the house? I know you said you have mixed galvanized and copper inside the house and like journeyman said you
need to eliminate the galvanized.
the house? I know you said you have mixed galvanized and copper inside the house and like journeyman said you
need to eliminate the galvanized.
Diehard
In Remembrance
based on his sketch that was provided earlier, the color coding shows what is copper vs galvanized. If correct, the sketch shows copper for the main up stream of the meter.
Based on the pictures that were provided, I see one fitting that appears to be galvanized steel. Some of the others, all though relatively poor quality pics, looks like a combination of brass and copper piping. Screwed brass piping with brass fittings.
Based on the pictures that were provided, I see one fitting that appears to be galvanized steel. Some of the others, all though relatively poor quality pics, looks like a combination of brass and copper piping. Screwed brass piping with brass fittings.
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Diehard
In Remembrance
This program needs a delete function!
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Diehard
In Remembrance
Depending on the people at the plumbing supply store, they may or may not be familiar with what is called NPSH Required vs NPSH Available, and how it relates to centrifugal pumps.
To keep it brief, a pump requires a certain amount of suction pressure to provide it's rated head(pressure) vs flow. So in order to calculate how much flow a particular pump can provide with a limited suction pressure, the "NPSH Required" by the pump should be compared to the "NPSH Available" from the water service. To help find that out, we would need the information I show in post #26 above.
For further clarification(or confusion), I refer you to the earlier post #18 by Valveman, who is a pump person. Where he said, "the pump may not get enough water to work properly." That is what I am trying to determine by trying to get a residual pressure vs flow test.
Makes me wonder if the city has a clue as to what their problem is with the lack of flow with 48 PSI static pressure available.Maybe they have a 1" water main running down you street. I'm being sarcastic!
When you say copper is almost done, I hope you started at the meter and included the branches going to the outside hose bib basement sink.
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We finally got all the copper replaced. We also checked the water meter and there are no obstructions (you can look right through it).
Long story short, changing to copper didn't help much (if at all). I did have significant rust, but apparently the pipes were sufficient for the capacity I was getting from the city.
Below are the tests that I ran.
Test 1: Static Pressure @ Laundry Sink = 45PSI
Test 2: Laundry Sink supply = 2.5GPM
Test 3: Residual pressure at outside spigot with laundry sink on = 0 PSI (it is bone dry)
Test 4: 2nd floor bathtub = 2 GBM
Test 5: 1st floor bathtub = 1.5 GPM (I suspect a clogged cartrage)
Test 6: Residual Pressure at outside spigot whith 1st floor bathtub running = 20PSI
The main line coming into the house is copper and we verified that the meter was not obstructed. We took it off and looked right though it. We also tested the city supply with no meter.
I did not recheck the inside garden hose outlet that I previously reported at 3.5GPM. I am wondering if the city supply flucuates or if my original recording was an error.
Long story short, changing to copper didn't help much (if at all). I did have significant rust, but apparently the pipes were sufficient for the capacity I was getting from the city.
Below are the tests that I ran.
Test 1: Static Pressure @ Laundry Sink = 45PSI
Test 2: Laundry Sink supply = 2.5GPM
Test 3: Residual pressure at outside spigot with laundry sink on = 0 PSI (it is bone dry)
Test 4: 2nd floor bathtub = 2 GBM
Test 5: 1st floor bathtub = 1.5 GPM (I suspect a clogged cartrage)
Test 6: Residual Pressure at outside spigot whith 1st floor bathtub running = 20PSI
The main line coming into the house is copper and we verified that the meter was not obstructed. We took it off and looked right though it. We also tested the city supply with no meter.
I did not recheck the inside garden hose outlet that I previously reported at 3.5GPM. I am wondering if the city supply flucuates or if my original recording was an error.
Attachments
Diehard
In Remembrance
Well sorry to hear that but I'm not a bit surprised.
The city has a problem with their piping. Size(s) and/or blockage somewhere.
Don't think you have much to gain with a pump unles you went to an elaborate system similar to what @Valveman had previously shown. But a good pump person should be allowed to comment on it.
I would be all over the city water department.
Do you have fire hydrants near by? They have to have adequate FLOW and Pressure. Consult the Fire department(and/or the water department) about their capabilities.
Totally unacceptable!
Diehard
In Remembrance
It just occurred to me, where are you located? Are you out in the sticks somewhere? Like somewhat of a remote area? That would help explain the problem.
I am in the burbs, not in the sicks. I measured my neighbors water at the outside spigot (right off the meter).
They are getting 45psi static (just like me) and an estimated 6-8GPM. They are getting at least 3 times what I am getting (and still complaining about lack of water pressure).
Does it sound like I need a new tap? I can get one for $800.
They are getting 45psi static (just like me) and an estimated 6-8GPM. They are getting at least 3 times what I am getting (and still complaining about lack of water pressure).
Does it sound like I need a new tap? I can get one for $800.
Diehard
In Remembrance
By new tap, I assume that means a new connection to the water main in your street.
I believe that's a question for your water purveyor.
I would want some type of guarantee that a new tap at $800 was going to provide me with a certain minimum flow vs pressure.
Personally I would find out what the main was capable of. Ask the fire department. Ask the water department. Otherwise you can't expect any more than what your neighbor is getting.
mike fiore
Well-Known Member
not saying this is the issue but i recently had a customer with same problem. after he had replaced all pipes in house and meter he called me and i found there was a leak between curb stop (water shut off in street) and meter in house. had to dig up street to repair. I hope that is not youre problem.
Diehard
In Remembrance
Yeah, the problem is definitely upstream of the meter. It's a question now as to whether the problem is between the meter and the main in the street or if the problem is in the main.
How did you find the leak in the buried line? (A sink hole?
)
mike fiore
Well-Known Member
I got lucky I could here the water after i shut meter off. sounded like a frieght train if you put youre ear to the meter.Yeah, the problem is definitely upstream of the meter. It's a question now as to whether the problem is between the meter and the main in the street or if the problem is in the main.
How did you find the leak in the buried line? (A sink hole?
