Spa Pump "Flo" error, now non-responsive

[Cooldood]

Hi All,
I have not found my exact problem(s) in any searches, so thought I might try posting.
Our hot tub has two Waterway 3 hp, 2 speed pumps, controlled by an Easypak 2000.
I have got well practiced at removing the pumps and replacing seals and fixing leaks over the years.

The recent issues started with a "FLO" error when the main pump was called for. I found the remedy was to press the pump button twice for high speed, then it would start and the slower speed could be selected. The controller was not that smart, so it often would be left calling for slow speed, the pump not starting and then the "Flo" message. The pump would hum loudly at that point. Never tripped breakers etc, I think the controller just gives up after a while.

So this weekend, I too the pump out.
It was a little hesitant to turn, but did turn, so I dismantled it, sanded the rotor, checked bearing, lubed everything up and reassembled. It then spun more freely by hand and I connected it to the tub and ran it quickly with no water connected and it was fine, a few seconds at both speeds.

Filled the tub. Was perhaps a little too eager, water level was about an inch over the skimmer turned on pump, worked, turned up speed, worked, noticed water while flowing over the weir into the skimmer, there was air where the filter should be, sort of like a column of water and air. Pump stopped.

I cannot get it running again. Pressing button on controller produces clicks, presumably relays in the controller, but nothing from the pump, no hum, nothing.

Please let me know what should I try next?
I see no obvious reset buttons etc. I tried powering the tub off for a while, no difference.

I guess I will drain and remove again, dismantle and check to see if anything looks wrong?
I could try swapping the pumps over?

I could make up a cable to plug it straight into the wall and bypass the controller.

 

[RDspaguy]

Check fuses. Post a picture of the circuit board.

 

[Cooldood]

The three main fuses are good, checked with meter after removing from circuit board. Did not check two tiny 2A glass fuses.

Control pack is 3 years and 4 months old. Still looks reasonable, although slight corrosion seen on some spade terminals. Pump is around 4.5 years, tub much older.

Here's a photo of the circuit board, let me know if you want to focus on one area, along with the schematic.

Water has cooled now and the display reads "FLO" seconds after it has turned on, as it must be asking for flow to turn the heater on and heat up to the minimum 59F. That is not a worry, not going to be below 40F here until next winter.

The other pump continues to work fine.
There is never any humming from the bad pump, so I guess it is not getting electricity, not thinking it is a capacitor problem. Think I will take it apart and check all the spades are connected in the back, as one seemed loose when I assembled it and I squeezed it a little but maybe it came off once pump started rotating and shaking? I will also be able to check if it is getting voltage from the control pack at that point too.

 

[RDspaguy]

You can check power at the board or the plug as well.

 

[Cooldood]

Confirmed that the socket on the controller is offering 240VAC where the pump cable plugs in. Next stop is the rear end of the pump and for that I really need to remove it after draining.

 

[Cooldood]

All sorted, hopefully.
There were three wires going to a black module on the inside of the back plane of the motor, coming from the windings, speed switch maybe? One black, one orange, one purple I think.
The black one was broken away from the tab, I resoldered it and all seems fine now.

Had to put silicone around the light fixture as that started leaking after the cleaning, so waiting 24 hours for that to cure, then I can fill the tub again, but the pump ran fine through the speeds a few times with no water in it.

 

[RDspaguy]

put silicone around the light fixture

Bandaid at best.
They are made of a clear plastic that is much more Brittle than the pvc of the other fittings in the spa. So the fittings themselves are prone to cracking at the flange, and the gaskets are not tightened as tight as with others so tend to leak sooner from deterioration.
The good news is that they are cheap and pretty easy to replace in most cases. Since the back is usually accessible for changing the bulb it is easy to get to. If you want to replace it post some pics and I will tell you how.