One of the main pool pump problems I hear from customers is"the pump is running but its not pumping any water". This is because the pump is not "primed" or at least not primed fully. When the pump is primed,it means the water is flowing through the pump at top speed,creating suction and pressure. Heres a few of the MAIN causes of a pump not being fully primed or primed at all:
1)The water level has dropped below the skimmer level and the pump is sucking air-or,if you have a weir flap in the skimmer it may get stuck in the closed or up position.(Also,if you have a skimmer basket with a round weir that bobs up and down inside,if the basket gets full of leaves it may get stuck in up position cutting off water flow).
2)Possibly the pump lid is not on tight or needs a new or cleaned/lubricated o-ring
3)If the pump has a closed face impeller,possibly debris has gotten past the pump basket(maybe broken basket?)and clogged impeller.....or,impeller shaft may be broken and the motor is spinning but NOT the impeller.
4)The plumbing going to your pump may be clogged
5)If you have a check valve on the inlet side of pump,part of it may have broken off and is blocking inlet
6)The inlet or outlet plumbing of pump has become loose,causing an air leak (often due to PVC pipe shrinking because pump ran dry and heated plumbing)
7)A diverter valve in front of pump is leaking air (through stem and/or cap o-rings)
8)The ceramic shaft seal is leaking water and/or air
9)Most pumps have a threaded plug before and after the impeller on the lower side (usually right side) of pump-these small plugs(about 1/4 inch) may come loose,letting in air.
10)If you have just installed a new pump or motor or the pool was drained or any plumbing has been redone or for any reason air has gotten into your plumbing line you may need to force water through your plumbing from the skimmer to the pump to remove air....this can be done with a device called a "drain jet" (shown below) that is available from a hardware store....it can also be used in reverse FROM the pump TO the skimmer to fix problem #4 above!...AND possibly FROM skimmer TO pump while pump is off to find air leaks for problems #5,6,7,8 and 9 above!
11)If your pump has a problem catching prime AFTER cleaning the pump basket,try installing a swing check valve in front of pump.
12)If pump is 230 voltage,is it running on only 115 volts?
Drain jet which is a canvas "balloon" that attaches to water hose and forces water down pipe - below that is more common rubber version.
1)Most often this is due to bearings in motor failing
2)Sometimes a blockage such as a filter backwash in the halfway positition can cause excessive noise
3)Sometimes the motor endbells can wear out letting the bearings
oscillate inside creating a rhythmic noise(more on this in motor
Capacitors shown below with microfarad value (uF) highlighted in orange. The smaller capacitor is for a 1 HP or smaller motor,the larger capacitor is for a 1.5-2 HP motor
1)Most likely a bad capacitor(shown above),which is located on the top of most motors under rounded cover and sometimes on the end of motor...it can be checked by an ohm meter - the correct reading would be a drop to zero followed by a slow rise in resistance. If you replace capacitor,the capacitor should be of the same value or at least within a few percent of value of microfarads (MFD or uF symbol on capacitor)
2)Stuck impeller usually due to debris caught in impeller,but can also be caused by calcium build up from leaking seal-to check,try turning motor shaft or impeller by hand with power off to see if impeller is stuck
Sometimes if you have an air leak somewhere in equipment, after pump shuts off the flow of water may reverse causing debris from filter to back up into the pump impeller. When the pump tries to start the following day,the motor cannot overcome the friction of debris to start. This may be a very slow process, perhaps hours after pump shuts off.
3)Motor has improper voltage or is simply old and start winding is burnt out
4)The bearings have seized
5)Also, a thermal overload switch will just shut off pump if it overheats.
6)If it is a waterfall,jet,or some type of pump that is not used very often debris can build up between stator and rotor - sometimes just turning the shaft a few times by hand before turning on can overcome this.
1)pump starts in low speed but will not start in high speed or go to high speed - this can be caused by a capacitor which is partially damaged (it has enough power to start at low speed and perhaps even go to high speed with the inertia,but cannot start at high speed). After changing capacitor,try running pump at night when its cooler to get a longer capacitor life.
2)pump starts in high speed but NOT in low speed...usually caused by obstruction (debris on/around/in impeller)- the pump does not have enough torque to overcome friction on low speed...clean out pump impeller and surrounding area,check for cracks in pump basket.
2-speed pumps should be started in high speed for a few minutes to catch prime and avoid the problem above...in fact most utility companies require some some of two speed controller to be eligible for rebate programs,which offer automatic switching to low speed after catching prime.
2)Upgrade your home liability policy