Intermatic Pool Timer Wiring

[sjeffers01]

After I replaced the pool timer I thought the problem with the pump turning on and off by itself was resolved. I should say assumed it was resolved. After installing the new timer Intermatic (T104) I checked to verify the pump turned on when it hit the first “on” tripper pin and went off when it hit the “off” tripper pin. I did the same thing with the second and third set of tripper pins and both went “on” and “off” on schedule. Then I changed one set of tripper pins to run the pump from 4 pm to 6 pm. I was in the pool when it turned on at 4:00 pm and after about ten minutes the pump shut off. Then a few minutes later pump turned back on. The pump ran for about five minutes and shut off itself again. I got out of the pool and checked the pool timer and the manual switch was in the “on” position. I realized the original problem was not fixed and the timer was doing its job. I did a search on the internet and discovered that the pump turns itself off when it overheats (thermal overload.) The possible reasons are the electrical supply connections are incorrect, low voltage because the gauge of the wires are incorrect, inadequate ventilation, or the motor is old because there is a short inside, usually across the windings. I ruled out ventilation so it is either the wiring or the motor. Should I check the voltage with my multi-meter to determine if the voltage is correct or just replace the motor? If I check the voltage can anyone provide instructions or can provide a website that does? I forgot to mention that the Pentair Clean and Clear Plus filter shows 10 psi when the pump is on. Is that normal?

[PoolDoc]

If you know how to do so, check the voltage while the pump is running.

OR, engage the multimeter with the pump OFF, and then have someone turn it ON while you are watching the voltage. It shouldn't drop more than 3% -- 4 volts at 120; 7 volts at 240.

It's harder to check for a short across the windings; you can check resistance, but unless you know the 'good' value, it may not tell you much.

Do you have an ammeter? (Amp-meter)

. . . I'm going to ask Mark to take a look; he understands electric motors better than I.

[mas985]

I doubt it is the winding's. Winding's are usually shorted or opened on failure so the motor will trip a break or won't run at all.

If the pump is turned on but after a few minutes shuts off on it's own, then it is likely the thermal limiter switch tripping. This is caused by overheating in the motor which in turn is usually caused by bad bearings in the motor or even a problem with the impeller. Under voltage and over voltage can cause the problem as well but that is pretty rare. If you are comfortable checking the motor voltage, you should probably do that first just to make sure.

Is the motor loud when running?

How old is the motor?

[sjeffers01]

I found instructions for testing a pool pump with a multi-meter at Inyo Pools website. I will test the pool pump this afternoon. Testing to check for a short across the windings sounds too complicated for me and way beyond my skill level. I don't have an amp-meter. If I have to replace my Pentair 3/4 HP Whisperflo single speed motor, can I buy a 3/4 two speed motor instead? Is the quality of an OEM motor equal to Pentair's replacement motors? I think the pool pump is at least a few years old. I have to see if there is a date on the pump and will update thread if its older.

[mas985]

Yes you can replace your current motor with a two speed. Is your pump the WF-3 or the WF-23?

Pentair does not make motors, they usually use a branded A.O.Smith now branded as Century motors on their pumps which are also sold aftermarket.

[PoolDoc]

The 2 speed motors are pretty expensive. Since you have a small pool, if your motor is shot, you might be better off getting a 2-speed above ground pump:
Hayward SP15922S Power-Flo Matrix 2-Speed


Here's a link for replacement motors:
http://www.a1poolparts.com/-strse-Mo...Categories.bok

[sjeffers01]

I agree that buying a new pump is better than paying for a new 2 sp motor. It costs more than a new pump to replace the motor because I would have to buy some other parts to install it. I checked out the Hayward SP15922S and it is 1 Hp. The Pentair Whisperflo pump I have is 3/4 HP and it is too big for my 8190 gal pool. Would a 1 HP be ok or should I look for a 3/4 HP 2 speed pump?

[mas985]

Actually, the Whisperflo is a larger pump than the Matrix. You can't always go by label HP when sizing a pump, you have to compare head curves for a true measure of a pump's power. For example, on typical AG pool setup, the Whisperflo will deliver about 53 GPM but the Matrix will deliver only 50 GPM.

[PoolDoc]

What he said.

You could use a smaller pump, but as far as I know, an above-ground 3/4 HP with 2 speeds is not available.

[Pappy]

Has it been verified that the pump is wired for 120v rather than240v?