Low Pressure at Jets

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pool owner 43

Low Pressure at Jets

Postby pool owner 43 » Sun 01 Mar, 2009 12:41

Hello, I have a "0" pressure reading on my pool gauge, although my spa is returning water into my pool at a decent rate. Also, my pool sweep is not moving much at all, but the suction is strong.

When I turn on my spa (jacuzzi mode) the pressure on the gauge raises, but the jets are not pumping water into the pool at full velocity. Maybe half or two thrids.

I'm not really good with plumming, and do not have channel locks, how can I fix this, and what might the problem be? HEEEEEEEEEEEEEEEELP! :wtf:
Last edited by Larry on Sun 01 Mar, 2009 16:22, edited 1 time in total.
Reason: Moved to a new topic


Low Pressure at Jets

Postby Guest » Sun 01 Mar, 2009 16:21

Sounds like a pump issue. Could be the motor is getting tired or a partially clogged impeller.

Could you post details about you pump and the age/ condition/ history of your pool.
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Low Pressure at Jets

Postby Larry » Mon 02 Mar, 2009 04:00

my pool sweep is not moving much at all, but the suction is strong

This seems to point to a pump problem. If the suction pressure falls when the cleaner or vacuum is attached, the pump doesn't have the power to keep up the same water flow.
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Low Pressure at Jets

Postby Ray1031 » Mon 02 Mar, 2009 10:12

I am guessing a couple of things from your post - and not meaning to be rude in anything you read here/only helpful ...
First, I gather that you are a fairly new pool owner with little problem experience so far.
Second, you are not what most of us consider a "handy" person - your primary problem solving experience with household and other problems (car/electrical/plumbing/etc.) is to reach for the phone and call a professional - or a knowledgable friend.
Third, you have a  pool with an attached spa, which share the same equipment but run through seperate  "switchable" plumbing. You are moving water when you draw from the spa, but not the pool ... though even with the spa you are not moving it at the rate you believe you should.

Yes, it is definately a pump problem ... in that the pump is not moving the water as it is intended to. The question is "Why?" The answer to that could be varied, but here are what I've found to be the most common reasons:

Dirty Filter: As filters become dirty they restrict water flow ... cartridge and diatomaceous earth can plug to the point that you will not move water at all (especially if you have live algae present in the pool - never run your pool without chemicals). Sand filters are more forgiving - but even they can eventually plug.
--The test for this: With a cartridge filter - remove the cartridge and try running the pool without it. With other filters try a backwash (if possible) or set your valves to bypass the filter and try running the pump (also - if possible).
--The fix: Clean or replace the cartridge, backwash and clean an Earth or sand filter.

Loose Plumbing problem: If your pool has ever run for an extended period "without moving water" Plumbing fittings can shrink, warp and/or distort. This allows the pump to suck air, rather than water. Between the pump and filter, this distortion will appear as a leak - water seeping/squirting/dribbling out - that is on the pressure side. In front of the pump, on the suction side, it will suck in air rather than water.
--The test for this: Grab the pipe feeding your pump and try to wriggle or turn it. Being albe to do so (with your hands), even a little bit, indicates a loose connection which may be sucking air.
--The Fix:  Replace or reseal and reseat the fitting Plumbing. Usually, the best fix is replace rather than trying to reseal.

Physical Pump problem: (1) A partially plugged impellor has already been mentioned ... this causes problems because of "cavitation" - meaning the debris lodged in the impellor actually generates/causes air as the impellor turns in the water. So it breaks/or partly breaks its own suction. (2) A pump lid problem: a badly seated or dirty O-ring or gasket can allow air into the system. Wear, splitting, or damage to the O-ring or gasket can cause the same. A cracked or damaged lid will let air in and lessen suction. (3) If the drain plugs have been removed and reseated, they could have become cross threaded or been over tightened, splitting the pump housing (ever so slightly - even the smallest crack or defect in the "suction" side will allow air in and lessen/halt water flow). (4) Back to the "running without moving water" thing: Some pump housings can themselves become "heat distorted" or may split if run for long periods without moving water.
--The Test:  These are all 99% physical. You take things apart and "look" - if you are not a handy person, but have a friend who is, often the cheapest method of determining one of these situations is a couple of hours with your friend, his tools, and a couple of beers.
--The Fix:  For a clogged impellor - clean it out. Water forced backwards through it may work - tiny screwdrivers, a wire coat hanger or probes can push/pull things loose - and needle-nosed pliars may help. Above all here, "do not damage the impellor". For bad seals, cracked damaged lids, pump housings - Replace the damaged part ... or try cleaning a dirty or debris ridden part.

An old, calcified heater heater can also cause what you have described - especially is you have not paid attention to your PH and the water has been alkaline (high ph). This will deposit/build scale on internal heater parts/tubes. A bad/defective governor or water flow regulator inside of a heater can also cause this problem.
--The test: Only if you can bypass the heater ... otherwise - you need a pro for this.
--The fix:  Call a heater professional unless you or a friend "knows" what you are doing.

Plumbing plugging due to vacuumed debris: Since you have "indicated" that you have two seperate plumbing set-ups (one-pool and one-spa) feeding the same equipment and you are having pretty much the same trouble with both ... this is not likely unless the plugging is inside of the valves in front of your pump.
--The test: If possible, you can try opening up the valve and looking - but only if it is designed to be opened (many are not).
--The fix: Clean out the valve.

Suggestion:  If there is any warpage of the pump basket ... this is a good indicator that the pump has indeed rujn for extended periods without moving water - they get hot (damned hot) when water is not moving through them - look at the pump/plumbing connections closely.

Suggestion:  If there is any warpage, cracks, chips or damage to "any" basket in your pool, or if they do not fit snuggly - replace them.

Suggestion: Annually check/inspect all O-rings and gaskets (that you have access to) in your system. Replace anything damaged or "questionable". A cheaper option to having to later call a repairman.

Hope this helps. 

Ray10311 is an experienced pool professional with 25 years experience

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