Both pumps stop working

[bschooly]

Today I noticed that both pumps (main and booster) stopped working. I checked the breaker and I also checked the power to each pump (at the output terminals of the timer) using a multi-meter. Both have power. When I flip the timer to the "on" position I detect a very slight thump sound (not a hum).

I can see that a pump may fail but both at the same time? What is going on here?

Main is pentair wisperflow 2 hp and booster is 3/4 hp challenger. I rebuilt the booster recently (3 weeks ago) but other than that nothing out of norm has taken place.

Bill

 

[DanielP]

Did you try each pump without the other pump plugged in? It does seem unusual to have both go out at the same time. If a pump were to lock up, it would draw more current which would cause a voltage drop. If one pump causes a voltage drop, the other pump will have to draw extra current to make up for the lost voltage and current is what heats up the windings in the motor. I'm not an electrician, but I think while it's a possibility, it would be uncommon for both to get damage before tripping a breaker if the wire and breaker were properly sized.

 

[bschooly]

Did you try each pump without the other pump plugged in? It does seem unusual to have both go out at the same time. If a pump were to lock up, it would draw more current which would cause a voltage drop. If one pump causes a voltage drop, the other pump will have to draw extra current to make up for the lost voltage and current is what heats up the windings in the motor. I'm not an electrician, but I think while it's a possibility, it would be uncommon for both to get damage before tripping a breaker if the wire and breaker were properly sized.

Well I thought that as well but I tried turning on the just the main w/o the booster and the results were the same.

 

[bschooly]

Anybody got a hint? Could a problem with one pump (maybe drawing too much load) cause the other to not work as well?

I checked the power at the main pump and it is getting 220V.

Could a bad capacitor cause this?

 

[Kiss4aFrog]

When both go out at the same time it's usually always an electrical circuit problem and not the motors.

If one goes bad in some way and starts drawing too much current it would be a problem for the second but it should blow the breaker. Are they both on the same breaker and same timer ??

Depending on how comfortable you are with it you can kill the breaker, jumper the timer and try the pump or pumps with the timer bypassed and out of the circuit in case it's developed a bad contact and it's impeding current flow internally.

The thing stuck in my mind is if you're turning the pumps on with the timer and you can leave it on and nothing is smoking, humming or pumping then somewhere you have an open in the circuit since the breaker isn't popping. If you haven't done anything physical near the wiring like digging, landscaping or inside like remodeling or whatever ... something that might have damaged the wiring you are pretty much down to breaker or timer and again both motors failing at the same time is pretty remote but it would be the third and final thing to check out.

 

[bschooly]

When both go out at the same time it's usually always an electrical circuit problem and not the motors.

If one goes bad in some way and starts drawing too much current it would be a problem for the second but it should blow the breaker. Are they both on the same breaker and same timer ??

Depending on how comfortable you are with it you can kill the breaker, jumper the timer and try the pump or pumps with the timer bypassed and out of the circuit in case it's developed a bad contact and it's impeding current flow internally.

The thing stuck in my mind is if you're turning the pumps on with the timer and you can leave it on and nothing is smoking, humming or pumping then somewhere you have an open in the circuit since the breaker isn't popping. If you haven't done anything physical near the wiring like digging, landscaping or inside like remodeling or whatever ... something that might have damaged the wiring you are pretty much down to breaker or timer and again both motors failing at the same time is pretty remote but it would be the third and final thing to check out.

Thanks but there is power to the main pump. I took the cover off the back and tested with a multi-meter. I'm stumped. I'm going to replace the capacitor and see if that does anything. Probably need a spare some day so no harm done....

Breaker does not trip.

 

[Kiss4aFrog]

If the Cap is bad and there was a safe way to spin the shaft or impeller manually the motor should run. When you checked for power at the motor where you checking from the wire to ground for power ?? Does your timer switch both legs of the circuit or only one leg, SPST or DPST ??

 

[bschooly]

If the Cap is bad and there was a safe way to spin the shaft or impeller manually the motor should run. When you checked for power at the motor where you checking from the wire to ground for power ?? Does your timer switch both legs of the circuit or only one leg, SPST or DPST ??

The motor turns easily and turning it manually doesn't help it start. I tried another capacitor and that didn't do it. So I thing that theory is out. I tested the power on the pump by touching one lead to ground and the other to each of the 110 hot wires and I get 110 for both. Single timer controls both pumps. Very standard setup (pool update was done about 4 years ago with all new components),

It seems the main pump may be "dead". Is it common for it fail within 4-5 years? Anyway, I'm not convinced yet. Why isn't the booster running? Seems improbable that both pumps failed at or near the same time. And then there's this new piece of info:

I notice when I flipped the timer to the on position that the lights to the SWG lit up for a moment then went dark. This seems to indicate something in the overall power source. Could a breaker fail softly? perhaps allowing only so much current?

Needless to say I'm running out of time before the pool turns green. ANYONE else know what is going on? If not, it is looking like I'll have to call a local pool service co.

 

[Qwaxalot]

You have to check for 220 volts BETWEEN the two hot legs, not from each leg to ground.
With one side of the 220 V circuit out (which is probably what's wrong), you'll read 110 to ground on each side!

 

[bschooly]

You have to check for 220 volts BETWEEN the two hot legs, not from each leg to ground.
With one side of the 220 V circuit out (which is probably what's wrong), you'll read 110 to ground on each side!

You are correct! I didn't realize "My way" was wrong. I thought if you got 110 to each lead the affect was additive.

I have 220 coming into the timer but it looks like the switch or the wiring in is somewhere is bad (its output leads show no voltage across the terminals),

Thoughts on where to look? Time for new timer?

 

[bschooly]

Well here is the culprit:



Bad contact. When flipped to 'on' position, the contacts didn't touch. The smaller arrow shows a melted area. The second, a bent blade. Stuffed a twig (as a test) behind the blade and powered her up and everything ran just fine. I wished I looked at this sooner as a possible source of the problem. The 110v tests I did wrongly led me to believe the problem was elsewhere.

Thanks once again.

 

[Kiss4aFrog]

That's why I was asking about how you tested for power and why I suggested you jump the timer. A lot of folks will test 220 like it's 110 and it just doesn't work that way.

The question now is what caused it ?? Do the long arms for the contacts look discolored from heat (excessive current) ?? Are the connections at the timer loose, damaged or dirty/corroded ??
You might have a motor or wiring connection problem and now would be the time to find out. Do both motors spin freely, bearings smooth and quiet (circuit dead!). Are the wiring circuits for both motors undamaged, connections clean and tight ??

The smaller arrow pointing to the melted structure of the connection is a result of something and it could just be a bad connection on the other side at the terminal but you'd want to figure it out before dropping in a new timer.
Can you post a picture of the other side, the wire terminals ??
What size breaker do the pumps run on ??

 

[bschooly]

That's why I was asking about how you tested for power and why I suggested you jump the timer. A lot of folks will test 220 like it's 110 and it just doesn't work that way.

The question now is what caused it ?? Do the long arms for the contacts look discolored from heat (excessive current) ?? Are the connections at the timer loose, damaged or dirty/corroded ??
You might have a motor or wiring connection problem and now would be the time to find out. Do both motors spin freely, bearings smooth and quiet (circuit dead!). Are the wiring circuits for both motors undamaged, connections clean and tight ??

The smaller arrow pointing to the melted structure of the connection is a result of something and it could just be a bad connection on the other side at the terminal but you'd want to figure it out before dropping in a new timer.
Can you post a picture of the other side, the wire terminals ??
What size breaker do the pumps run on ??

30 Amp breaker. All connections look tight and the other side looks normal. The contact surface is slightly burned-looking. Main pump is quiet. Booster makes more noise than I care to have but I believe is sound electrical wise. I'm actually using the timer right now (has worked fine so far) by placing a piece of foam behind the fixed prong end so when the switch triggers the two prongs make contact.