Pumps & Motors
This page will help you understand and solve many
problems on your pump and motor. If you need extra help
e-mail me with your problem.

If you are thinking about purchasing a new pump and motor
please read about sizing in our
on-line store. We have many
selections available.
Can you explain how a pump works?

Swimming pool pumps consist mostly of the same basic parts: the pump pot (where the
basket is contained), vacuum chamber or volute, the impeller and the shaft seal. The water
enters the pump pot, which keeps a reservoir pooled to allow the pump to prime itself.
All of the water that passes through the pump must first pass through the pump basket. This
collects any debris that has been sucked up preventing it from passing through and clogging
the pump impeller.
The action of the pump takes place in the vacuum chamber; this houses the impeller that
moves the water. The impeller attaches to the motor shaft and spins inside the vacuum
chamber. The impeller will either be open faced, which are bronze with the visible vanes, or a
closed-faced impeller, which are plastic and have a cover over the vanes with an opening in the
center to allow the water to enter.
Last in line is the seal. The seal has the responsibility to prevent the water from leaking out of
the vacuum chamber. A seal must keep the water in the wet end of the pump so the dry side
will stay dry.
Swimming pool pumps use centrifugal force to move water through the circulation system. The
definition of centrifugal force is an object moving away from the center, like a roller coaster.
When water enters the middle eye of the spinning impeller, it is forced out through the
impellers vanes. As the water is thrown out to the edges of the impeller there is a reduction of
pressure in the eye of the impeller, and this creates a vacuum which will draw more water
into the impeller.
The water thrown out of the impeller is forced up and out at the top of the vacuum chamber and
moves on through the rest of the circulation system.

What causes the pump to lose its prime?

Could be a number of things; Air leak in suction line, water level is below the skimmer, baskets
are clogged (skimmer and pump), suction valve in wrong position, lid of pump is loose or
o-ring is damaged, bad gasket or loose connection between pump and pump housing.

How does low pump flow and filter pressure correlate?

If you have low flow and high filter pressure it usually means your filter is dirty or your return line
is restricted or blocked. Check all return valves and make sure the backwash valve is in the
correct position.
If you have low flow and low filter pressure, it could mean an air leak or block in the suction line,
clogged baskets or clogged impeller.

How can the pump get blocked when there is a basket inside?

Most pumps have a basket inside which catches the debris that travels from the pool to the
filter. Small debris like sand and silt pass through to the filter, but large debris like leaves and
bugs get caught in the pump basket or trap.
If a basket gets too full or a basket gets torn, larger debris will then travel through the pump pot
to the impeller where it can get jammed. When this happens, the pump has to be broken apart
in order to clean out the impeller. This is also the reason that whenever a basket-
skimmer or pump-deteriorates, we change it immediately. Preventative maintenance is the key.

I hear a loud pitched screaming from time to time coming from my motor. What is causing
this?

The bearings inside your motor are slipping and causing the noise. Unfortunately, your motor
is going bad and soon will need to be replaced. After the bearings start to whine, within a few
days they will start to scream loudly much like a chain saw, which will attract your neighbor.
Then you should call us.

Why do some pumps make a lot of noise where others are quiet?

Could be a number of reasons...An aging pump usually is louder as the bearings in the motor
are getting worn. Newer pumps and motors are quiet especially the
Whisperflo by Pentair.
Also, in some instances a pump can be sized incorrectly. Sometimes the homeowner opts for
a larger pump-thinking that bigger is better-but his system is not equipped for it, as he may
only have 1.5 inch plumbing. In this case, the pump will sound loud because the
water cannot travel as fast as the pump requires. The water is then broken down to the point
where air is pulled from it and the pump cavitates, which sounds very loud.
There are three types of pumps; Low, medium and high head. The latter being the more
powerful.

I heard that SDG&E are giving rebates on energy efficient pumps. Is this true?

Yes, in a nutshell, Sempra Energy will give a $125 cash rebate if you change out your pool
pump and motor unit for one listed on their list of energy efficient units. You have to drop down
a 1/2 horsepower though. So if you have a 2HP pump, you can purchase a 1.5HP
pump. We install it for you and you send in the receipt to SDG&E who will rebate you $125.00.
The pumps and motors listed are both energy efficient and more generally more powerful than
the older models. Some are high head pumps compared to medium or low head pumps,
which means they move more water-gallons per minute-than the older ones.
It has to be a licensed contractor who completes this work for you in order to apply for your
rebate.
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