Self-priming pump or what?

bob saunders

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We've have a problem with out water pump. The pump has decided not to fill the tinaco's on the roof. It however does give even pressure to give us water to the tap on occasion. Talked to several plumbers and they say that a cistern should have been built when the house was built to give constant water to the pump to prevent cavittion and they tried to tell the engineer but she refused to listen.
(we were not in country so didn't even know we had an issue) . The plumber seem to think this is the only solution to out problem. The other problem is now there is no place to put a cistern. Is there other options, like self priming pumps?
 

bob saunders

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There's water on the street 95 percent of the time, although on Saturdays the pressure and volume are less (wash and cleaning day) I would think a good self-priming pump would do the job. The current pump is self-priming I'm sure, just decided not to work correctly anymore.
 

cobraboy

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Jul 24, 2004
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We've have a problem with out water pump. The pump has decided not to fill the tinaco's on the roof. It however does give even pressure to give us water to the tap on occasion. Talked to several plumbers and they say that a cistern should have been built when the house was built to give constant water to the pump to prevent cavittion and they tried to tell the engineer but she refused to listen.
(we were not in country so didn't even know we had an issue) . The plumber seem to think this is the only solution to out problem. The other problem is now there is no place to put a cistern. Is there other options, like self priming pumps?
Bob, your biggest problem is the waater supply in Jarabacoa is inconsistent-you never know when it'll be on-and it is not under great pressure when it is on.

We check it all the time for filling our pool. Sometimes it's barely a trickle, not even enough to use a pump.

You may have to do what Don suggests and have a cistern built under your house. It's not that difficult, just a bit messy inside the house for a while. You shouldn't need a giant one for your house.

Youe engineer really screwed the pooch on this one.
 

cobraboy

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There's water on the street 95 percent of the time, although on Saturdays the pressure and volume are less (wash and cleaning day) I would think a good self-priming pump would do the job. The current pump is self-priming I'm sure, just decided not to work correctly anymore.
It may have burned itself out running dry due to the lack of pressure.
 

bob saunders

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It may have burned itself out running dry due to the lack of pressure.

I agree but it sounds fine, until you start to cut off the water supply then it lets out a high pinch squeal, like you would expect on cavitation. I always check next door before turning on the pump to see what the pressure and volume are like.
 

cobraboy

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I agree but it sounds fine, until you start to cut off the water supply then it lets out a high pinch squeal, like you would expect on cavitation. I always check next door before turning on the pump to see what the pressure and volume are like.
Just a little water will make a pump sound different, but that doesn't mean there is any significant water pumped, or to cool the mechanism...

If the water pressure is below the pump pressure...and I'll bet it is...you have a problem.

That's one big reasons cisterns are popular. When a pump is primed and check valve installed, you get water on command to the tinaco...
 

Chip

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Jul 25, 2007
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If the tinaco is too high and causing cavitation put an inline backflow preventer about 10 feet above the elevation of the pump.

BTW, if the pump is pressuring the lower part of the system it isn't a prime problem. You can always call me to discuss specifics if you want.
 

bob saunders

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Just a little water will make a pump sound different, but that doesn't mean there is any significant water pumped, or to cool the mechanism...

If the water pressure is below the pump pressure...and I'll bet it is...you have a problem.

That's one big reasons cisterns are popular. When a pump is primed and check valve installed, you get water on command to the tinaco...

It all makes sense, and this is what the plumber told us, but I was and am looking for away around having to tear up the floor in the parking area.
 

bakersindr

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If your pump is cavitating then a self priming one will not do you any good. Cavitating means the pump has sucked up all the available water is trying to pump air as well as the little water left. Try throttling the outlet of the pump. You will fill your holding tank slower but will not suck up the available water as quickly and cause the cavitating. A cistern would definitely be the answer if at all possible.
 
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Do you know if you have a check valve before the pump? I suspect your tinaco is draining back into the town water.
 

Lothario666

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If you do put in a cistern (Highly recommended), I would also recommend adding a float switch in the cistern to disable the pump when the water gets too low. (Also run a 'good' pvc pipe (not the cheap stuff) to the cistern for water level monitoring switches) A cistern in the center of the garage still allows you to park your vehicle. With the water situation getting worse and worse in the D.R., the more storage you have the better.
 

cobraboy

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Except the system I have has worked fine for the past year. Maybe I was just lucky up until now.
Much here depends on how much water is available. It's been dry for a while, and the access to water has been limited lately.
 
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Check valves are prone to failing. Usually just a bit of grit is all it takes. Taking them apart and cleaning them is often enough.
 

Lothario666

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Except the system I have has worked fine for the past year. Maybe I was just lucky up until now.

The system I have with a "cistern" and 3 tinacos has worked fine for the past 16 years, even when there was problems getting water from the street some of the time.
 

Lothario666

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I agree but it sounds fine, until you start to cut off the water supply then it lets out a high pinch squeal, like you would expect on cavitation. I always check next door before turning on the pump to see what the pressure and volume are like.

After re-reading this, it also sounds like your "engineer" besides not taking the advice to install a cistern, also did not install a pressure tank.

With a cistern there's absolutely no reason you would be turning your pump on and off manually if your "engineer" knew what she was doing when she had your water system installed. Your water system can and should be totally automatic.
 

Chip

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Jul 25, 2007
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After re-reading this, it also sounds like your "engineer" besides not taking the advice to install a cistern, also did not install a pressure tank.

With a cistern there's absolutely no reason you would be turning your pump on and off manually if your "engineer" knew what she was doing when she had your water system installed. Your water system can and should be totally automatic.

With all due respect Don that is very expensive to have the pump running all day long. We cut ours on once or twice a day.

While I do agree Bob should have a pressure tank I see no reason why he needs a cistern given the availability of water in his area.