OT: Help with pool pump information please

Jangchub says...

Quoted message said:

Can you help me figure out size pump I need. I have a
50x8 lap pool with a spa (which I rarely use and do not
need added power for). The pool itself is 50 feet from
equipment. We have a Hayward Super 2 3HP and it is
burning out because it is too large. The intake pipe is
2" the pool holds about 14,000 gallons. Can you
recommend which size pump I need. I have already
replaced two pumps in 6 years because I find out they
were too large for the pipe. Any help would be greatly
appreciated.

Quoted message said:

kind regards,
Victoria

Unless things have changed in recent years, the pump is
actually composed of two parts - the impeller, and the motor
which drives the impeller. Is it the motor that is burning
out? Or does the pump itself start leaking?

My pool is 18,600 gallons, has 1.5" plumbing, and the pump
has a 1HP motor. So your 14k gallons must be turning over
pretty fast. But I don't know that the pump being "too
large" would cause it to fail. Who told you is was too
large?

Maybe the hydraulics experts here can educate us.

I've never heard of this problem before but that doesn't really mean
anything.

For perspective, I have a 2hp triton pump with a 2" intake that runs both
the pool & a spa (25,000 gal combined). I burned out a pump motor after
about 7 years. Put new pump motor & impeller in at that time and it's been
fine.

Have you talked to the people who put the pool/pump in?

I think Hayward's web sight can help you with gal/pumpsize too.

Good luck.
"Jangchub" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Can you help me figure out size pump I need. I have a 50x8 lap pool
with a spa (which I rarely use and do not need added power for). The
pool itself is 50 feet from equipment. We have a Hayward Super 2 3HP
and it is burning out because it is too large. The intake pipe is 2"
the pool holds about 14,000 gallons. Can you recommend which size
pump I need. I have already replaced two pumps in 6 years because I
find out they were too large for the pipe. Any help would be greatly
appreciated.

kind regards,
Victoria

Peabody said:

Jangchub says...

Quoted message said:

Can you help me figure out size pump I need. I have a
50x8 lap pool with a spa (which I rarely use and do not
need added power for). The pool itself is 50 feet from
equipment. We have a Hayward Super 2 3HP and it is
burning out because it is too large. The intake pipe is
2" the pool holds about 14,000 gallons. Can you
recommend which size pump I need. I have already
replaced two pumps in 6 years because I find out they
were too large for the pipe. Any help would be greatly
appreciated.

Quoted message said:

kind regards,
Victoria

Unless things have changed in recent years, the pump is
actually composed of two parts - the impeller, and the motor
which drives the impeller. Is it the motor that is burning
out? Or does the pump itself start leaking?

My pool is 18,600 gallons, has 1.5" plumbing, and the pump
has a 1HP motor. So your 14k gallons must be turning over
pretty fast. But I don't know that the pump being "too
large" would cause it to fail. Who told you is was too
large?

Maybe the hydraulics experts here can educate us.

I called Hayward and they told me a 3hp motor was excessive and for
commercial use, not home pool use. I have two inch pipe. I went to
enough websites and then found a calculator and discovered I could use
a 1hp pump, or 1.5hp pump. The motor shuts off after a few minutes
then cools down and goes back on all day. The housing is also
leaking. The pump is barely three years old.

Yes, I spoke with Hayward and they said a 1.5hp pump should do it. I
hate when the pool breaks!

Brian Foster said:

I've never heard of this problem before but that doesn't really mean
anything.

For perspective, I have a 2hp triton pump with a 2" intake that runs both
the pool & a spa (25,000 gal combined). I burned out a pump motor after
about 7 years. Put new pump motor & impeller in at that time and it's been
fine.

Have you talked to the people who put the pool/pump in?

I think Hayward's web sight can help you with gal/pumpsize too.

Good luck.
"Jangchub" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Can you help me figure out size pump I need. I have a 50x8 lap pool
with a spa (which I rarely use and do not need added power for). The
pool itself is 50 feet from equipment. We have a Hayward Super 2 3HP
and it is burning out because it is too large. The intake pipe is 2"
the pool holds about 14,000 gallons. Can you recommend which size
pump I need. I have already replaced two pumps in 6 years because I
find out they were too large for the pipe. Any help would be greatly
appreciated.

kind regards,
Victoria

Jangchub says...

Quoted message said:

I called Hayward and they told me a 3hp motor was
excessive and for commercial use, not home pool use. I
have two inch pipe. I went to enough websites and then
found a calculator and discovered I could use a 1hp
pump, or 1.5hp pump. The motor shuts off after a few
minutes then cools down and goes back on all day. The
housing is also leaking. The pump is barely three years
old.

It sounds like you're getting excessive heat buildup within
the motor. It has built-in thermally-triggered circuit
breakers which shut things down when the temperature gets
too high. And when everything cools down again, the circuit
reconnects and starts the motor again. So you're apparently
cycling back and forth. That's not good at all.

The heat shouldn't be building up that much. If you are
also getting a water leak out of the pump, it may be that
the impeller isn't properly adjusted, and is dragging on the
pump housing, which in turn could cause the motor to work
too hard.

But I'm just guessing really. If you have access to a pool
service technician, that's probably your best shot.

What I'm having trouble with is the idea that the motor
being too powerful is the problem. I would have thought
that all motors of this type would try to turn at the same
speed, which is 3450 rpm on 60Hz power, whether they are 1HP
or 3HP, because the motors are synchronous, but maybe I'm
wrong about that. The plate on the motor should show the
rpms.

Or perhaps the physical size of the motor is so large that
it doesn't fit properly to the pump body, or doesn't draw
enough air ventilation to cool properly and prevent
overheating.

But I don't think I've ever seen a 3HP pump motor, so as I
said before, I'm really just guessing. You need to find
some local expert to physically inspect your setup.

Maybe someone else will have some ideas.

Thank you for your response. From what the Hayward technical
department told me, a 3hp pump is used for commercial applications and
because I have two inch pipe the motor builds up pressure in the pipes
because it is not flowing freely, but suffocating in the smaller
pipes.

The pool guys who fix things all wanted 650 dollars JUST for the
motor, plus installation and tax. What I wound up doing was searching
high and low for a new motor with all the O rings and fittings, new
impeller and I paid 250 dollars for that. The pool guy will come and
install it to the housing and he said it should be a one to one and
half hour job at 85 dollars an hour.

So, buy finding a new motor on my own, we saved quite a bit. It won't
be done till next week (I hope), but I'll report what the results
were.

Thank you to everyone who helped.

Victoria

Peabody said:

It sounds like you're getting excessive heat buildup within
the motor. It has built-in thermally-triggered circuit
breakers which shut things down when the temperature gets
too high. And when everything cools down again, the circuit
reconnects and starts the motor again. So you're apparently
cycling back and forth. That's not good at all.

The heat shouldn't be building up that much. If you are
also getting a water leak out of the pump, it may be that
the impeller isn't properly adjusted, and is dragging on the
pump housing, which in turn could cause the motor to work
too hard.

But I'm just guessing really. If you have access to a pool
service technician, that's probably your best shot.

What I'm having trouble with is the idea that the motor
being too powerful is the problem. I would have thought
that all motors of this type would try to turn at the same
speed, which is 3450 rpm on 60Hz power, whether they are 1HP
or 3HP, because the motors are synchronous, but maybe I'm
wrong about that. The plate on the motor should show the
rpms.

Or perhaps the physical size of the motor is so large that
it doesn't fit properly to the pump body, or doesn't draw
enough air ventilation to cool properly and prevent
overheating.

But I don't think I've ever seen a 3HP pump motor, so as I
said before, I'm really just guessing. You need to find
some local expert to physically inspect your setup.

Maybe someone else will have some ideas.

"Peabody" <[email hidden]> wrote in message
news:oP3eg.27892$Ce1.23884@dukeread01...

-snip-

Quoted message said:

What I'm having trouble with is the idea that the motor
being too powerful is the problem.

This isn't limited to pool pumps - heating and air-conditioning systems
have the same potential problem. If the unit is over capacity, it will
go on and off more often. For much equipment, it is the on/off cycles
which eventually cause them to fail. You may have heard of a similar
debate amongst computer users - do I leave my PC on 24/7 or turn it off
at night? Hopefully the above answers that question. Ask a plumber or
HVAC person about this and you'll get the same answer.

Of course, undersized isn't good, either, which is why you want "right"
sized.

-S-