Flashing FLO still won't go...

[Methuselah]

I got some vinyl tubing and couldn't get the circ pump to move water, even after I primed it.

I found where the hot lead plugged into the board and clamped it while it was running - .49 Amps.

Either I got the run capacitor leads reversed when I connected it back to the motor - or something inside the pump is shot.

Cap is not polarized and can be connected either way. Some motors have a start winding and centrifugal switch that disconnects when it spins up, could be bad contacts on it if present, capacitor could be low in value and causing the issue too.

I agree with JamesW on how to check it and his assessment of your amps reading, but I'm going to repeat myself ... if you replace that pump you are probably either needing, or will need it sooner rather than later, and taking it to a motor repair shop would also have resulted in a known good motor (and likely fix).

I'm like you, would rather spend time than money, so I understand your process. If you are mechanically inclined, you may be able to repair the motor yourself too ... just lightly sand the commutator, replace brushes if needed, and if the bearings are bad and won't come out easily perhaps said motor shop will remove them for free if they are sympathetic. For them it's probably a 30 second process.

Knowing nothing about your tub until you posted the pictures, I can see that circulation pump is directly in line with the heater element and flow switch, so am thinking the main pump and aux have little to contribute to actuate that flow switch. Seems like that pretty much guarantees the problem is the circulation pump now that you have a new flow switch. Also, obviously that flow switch is installed in the correct position.

I hope you get it up and running soon, looks like you are in the home stretch

 

[JamesW]

@JamesW - nothing jamming the impeller but I take it that heavy amounts of slop are abnormal? (That's a 4mil hex wrench I've got in there to show how far it wobbles.)

That looks bad and it is probably rubbing and preventing it from spinning.

Remove the impeller and replace it if possible.

You will also need a new seal.

Getting a new pump is probably going to be the best choice unless you can get a few cheap parts and get this back to working condition.

Try removing the impeller and then see if the motor spins.

 

[Methuselah]

Too much slop, I'd bet the bearings are shot.

Ebay search: "Electric Motor Bearings"

If motor repair's a DIY for you, only concerns now would be whatever else was bad when you take it apart. If it was wobbling enough to leak, water may have sprayed into the motor too (probably not worth fixing if that happened).

For me, it would be fun to tear down the motor anyway, so that's why I posted...

 

[RDspaguy]

Do these Sundance Heaters have screens inside them? Or are these heaters known for accumulating buildup (especially on hard water) and preventing the correct flow rate?

Any heater can accumulate scale and restrict flow. Yours has a removeable element, so you can take it apart if you like. There are other places in the plumbing that can become clogged as well.

If you remove the circulation pump to check the impeller, perhaps there's an electric motor repair shop near you that can change bearings, turn down the commutator and replace the brushes...

Several years ago I had this done to a $100+ motor for $4 or $5 bucks.

Not that kind of pump, and it was WAY more than several years ago at that price.

.49 Amps.

At 240v is 120w, nearly double the rating of the motor.

heavy amounts of slop are abnormal?

Laing pumps are magnetic drive, so there is no physical connection between the impeller and motor, and no moving parts in the motor. The rotor is on the impeller, and the stator is the "motor" part on the back. The impeller floats, and often will not work without water in the pump. So, yes this amount of play is normal. This also makes imbalance (from debris or scale) a huge problem, like an unbalanced washing machine, that can wobble and lock the impeller and damage the motor. These pumps were originally used in closed chemical and heat exchanger systems where they last almost forever. Put them in a spa and you get about 3-5 years on average.

 

[bucci man jr]

Well, even though @RDspaguy indicates that the "slop" I showed in the pic can be normal - I'm going to replace the pump (with the updated 98W version from Sundance - no wait, it's actually made by Grundfos!) because one thing I never mentioned was...the mfg date on the pump from my spa is 2002! So I guess I beat the odds. And if it somehow isn't the cause...it soon would be.

@JamesW & @Methuselah - I'd love to be able to repair an electric motor someday - but this is not that day. My best tools at this point are mouse, keyboard, and credit card!

I'm a Sherlock Holmes type of troubleshooter - in the end, I want conclusive proof instead of guesswork, and you all helped me to that end.

Thank you all - I really appreciate the input and the community of helping others!

 

[RDspaguy]

wait, it's actually made by Grundfos!

Get a laing.

 

[bucci man jr]

Get a laing.

But..but...but...you said they so often fail in 3-5 years, I thought Laing was a bad proposition? The Sundance one is already shipped; guess I'll have to take my chances.

 

[RDspaguy]

I just prefer Laing. I'm surprised they went with grundfos, unless they've got something new. I haven't seen a grundfos in at least a decade. Nobody has used them since the 90's that I'm aware of. But I don't ever see newer tubs.

 

[bucci man jr]

"Flashing FLO" has left the building!

Many thanks again to all who replied. Pic of the full Flow Switch and the new Sundance (Grundfos) Circ Pump.

Now, if someone could just describe how to test a Flow Switch with a multimeter, I'd write a complete "sticky" guide for diagnosing/troubleshooting the "Flashing FLO."
I tried to test my old Flow Switch with a meter, but I can't tell if it's broken or if I'm doing something wrong. I put one probe on the post, and the other probe onto the metal strip (hard to get past the "button", but I did) and pushed the strip against the post. But I can't get a continuity reading from it. Does that conclusively prove it was bad, too?

 

[Methuselah]

You asked an "electronics" question.

If two wires it's a switch, three it'd be a powered sensor. Likely two wire.

To test (the latter) for continuity you disconnect the connector and measure with and without enough flow to actuate the switch.

In-circuit you (probably) check voltage across the CONNECTED wires. When actuated if the switch closes, contacts short and sensing voltage across it goes toward/near/at 0V. Likely DC.

Using continuity if the switch is in open position you are INJECTING a voltage (or constant current) and conceivably could damage the controller board's sensing circuit. On the other hand if it's in closed position you might just read continuity if contacts are in good condition.

Continuity checks are almost invariably reserved for unpowered circuitry. Unless you know what you are doing, troubleshooting an electrical or electronic circuit can at best cause damage, at worst be deadly.

Try measuring continuity on the contacts of your old flow switch if you still have it...

I'm glad you got it fixed. If I had to guess the flow switch you replaced was good, but I bet it was a heck of a lot cheaper than calling a repairman!

 

[JamesW]

Now, if someone could just describe how to test a Flow Switch with a multimeter, I'd write a complete "sticky" guide for diagnosing/troubleshooting the "Flashing FLO."

 

[JamesW]

 

[Cashmeout]

Push water into the pump from the skimmer or vacuum the water through the returns with something like a shop vac.