My pool, like most of the pools I've seen, use an Intermatic
mechanical timer to turn the pool pump on and off. It does not seem
that there are any low cost digital timers available.

Is there any reason I could not use an irrigation timer and relay like
those used on sprinkler pumps? The only drawback I can see is that
its a bit more complicated to simply turn the pump on whenever you
wish using the digital timers vs throwing a mechanical switch.

On Mon, 22 Jun 2009 08:47:18 -0700 (PDT), wrote:

My pool, like most of the pools I've seen, use an Intermatic
mechanical timer to turn the pool pump on and off. It does not seem
that there are any low cost digital timers available.

It isn't digital, but I ran my pool on an HB31R by intermatic for
several years. [until I closed the pool permanently] It is a 15amp
plug- in and cost less than $20.

Is there any reason I could not use an irrigation timer and relay like
those used on sprinkler pumps? The only drawback I can see is that
its a bit more complicated to simply turn the pump on whenever you
wish using the digital timers vs throwing a mechanical switch.

There is an over-ride on the Intermatic so you can turn it on or off
at will.

Jim

On Mon, 22 Jun 2009 08:47:18 -0700 (PDT), wrote:

My pool, like most of the pools I've seen, use an Intermatic
mechanical timer to turn the pool pump on and off. It does not seem
that there are any low cost digital timers available.

Is there any reason I could not use an irrigation timer and relay like
those used on sprinkler pumps? The only drawback I can see is that
its a bit more complicated to simply turn the pump on whenever you
wish using the digital timers vs throwing a mechanical switch.


I don't see any reason not to. Make sure your timer switch can handle
more watts than needed.

wrote:
My pool, like most of the pools I've seen, use an Intermatic
mechanical timer to turn the pool pump on and off. It does not seem
that there are any low cost digital timers available.

Is there any reason I could not use an irrigation timer and relay like
those used on sprinkler pumps? The only drawback I can see is that
its a bit more complicated to simply turn the pump on whenever you
wish using the digital timers vs throwing a mechanical switch.

That's a good idea. Just use a high current relay.

If you also have a Polaris booster pump it gets more complicated since
the booster pump can only be on when the main pump is on, but it isn't
on all the time that the main pump is on. On a dual Intermatic
mechanical timer you wire it so the Polaris pump timer doesn't provide
power to the booster pump even if the timer trips it on, unless the main
pump is on.

I had the exact same dilemma and then I found the Sylvannia SA310. It's a
heavy duty digital timer, perfect for pools. This is a newly introduced
product on the market and it's $95. I just installed it last week for the
pool and I love it so far.

http://www.amazon.com/Sylvania-SA310.../dp/B000KKNENU

scorpionleather wrote:
I had the exact same dilemma and then I found the Sylvannia SA310. It's
a heavy duty digital timer, perfect for pools. This is a newly
introduced product on the market and it's $95. I just installed it last
week for the pool and I love it so far.

http://www.amazon.com/Sylvania-SA310.../dp/B000KKNENU

Since most pool pumps are best run at 240 volts, it's not good for pools.

wrote:
My pool, like most of the pools I've seen, use an Intermatic
mechanical timer to turn the pool pump on and off. It does not seem
that there are any low cost digital timers available.

Is there any reason I could not use an irrigation timer and relay like
those used on sprinkler pumps? The only drawback I can see is that
its a bit more complicated to simply turn the pump on whenever you
wish using the digital timers vs throwing a mechanical switch.

Orbit makes a relay specifically for this purpose,
"http://www.orbitonline.com/products/Accessories/02/04/04/615/". It's
$39, "http://www.amazon.com/gp/product/B000I19I5E".

It's rated at 25 amps which is more than enough for even a 3HP pump
running at 208-230V (but not enough for a 2HP pump running at 115V).

Remember that the sprinkler valves are 24 VAC. Buying a new 24VAC 25A
relay will cost almost as much as the Orbit relay. Unless you can find
some appropriate relays on the surplus market, go with the Orbit
product. This relay looks like it would work (but I don't know the coil
current that the sprinkler timer can supply):

"http://www.electronicsurplus.com/commerce/catalog/product.jsp?product_id=71570"
"http://www.tycoelectronics.com/catalog/bin/TE.Connect?C=1&M=BYPN&TCPN=1393212-4&RQPN=T92S7A22-24"

If you have spare zones on an existing electronic sprinkler timer then
you don't even need to buy a new timer. I may do exactly this since I
have a 9 zone Orbit timer with three free zones.

The timer I have does allow you to turn zones on manually, and it's kind
of nice because you can specify the times for manual operation (up to 99
minutes).

The only thing you may have an issue with is that the sprinkler timers
limit the number of minutes per zone. I.e. my Orbit timer limits you to
99 minutes. But since I can program up to four start times per zone per
day, this would give me 396 minutes or over six hours, which is
sufficient, even for hot summer days where the pump is run for 3 hours,
twice a day. It's also a hell of a lot easier than switching the trips
on an Intermatic when you want to change times.

I've been having trouble with my Intermatic mechanical timer where the
trips loosen over time, then rather than tripping, they just slide until
they hit another trip thingee. I guess some Loctite would solve this,
but I like the idea of controlling it with my sprinkler timer, which is
inside the house.