Balboa pump #1 only works when circulating water (in low) , hums when pressing the button for fast speed

[Enrique]

Hi, 

I have a 7-person California Cooperage Hot tub similar to this

Everything was working fine a week ago, 3 days ago I went to the tub and the Jet1 button didn't work

The hot tube has 2 pumps (Pump#1 and Paump#2). Pump#1 has two speed modes: slow and fast (mode is changed by pressing the same button)

The hotub currently circulates and heats water. However, when I press the button for Jet1 (which controls pump#1) I hear a humming noise for like 1 sec and then the pump shuts down. Buttons for pump#1 becomes unresponsive and after a while the pump reactivates and circulates water again at low speed.

After restarting the pump several times and try to activate pump#1. I got an error message of 'heater may be dry'.

There is no issues with pump#2.

Do you think it is the starting capacitor? If so, why does it run in slow but not in fast?

PS: its -15F here, is this something I should attempt to fix when it's warmer?

Pump looks like this: 

Board is a Balboa MXBP501X PN 56549-01 pack

Thanks!!

[Enrique]

The humming noise makes me think that it may be the pump capacitor.

Now the question is:

the running capacitor (on the top of the pump)? 

OR

the starting capacitor (on the side of the pump)?

The pump does move and its not seized 

Thanks!

 

[CanadianSpaTech]

Usually the start cap gets the pump spinning in low speed and then the run cap keeps it going. If a bad start cap it won't start unless it is helped to spin by placing a screwdriver is the shaft slot at the back of the motor and giving it help to start. If it is a weak run cap then it might not stay running. Now does the spa have a circulation pump for filtering and heating? If it does then it will still filter and heat and your issue with pimp 1 is a separate issue. I suggest opening panel and getting to the back of pump 1 and removing the dust cap that is at the back of the pump and helping it to spin when it hums and see if it will start up.

[Enrique]

thanks, Ill try that

pump #1 has two speeds: low and high

Low speed is used to circulate (no dedicated circulation pump I don't think). In other words, I can see the shaft of pump#1 moving in low speed when the hot tub needs circulation of water (for heating and filtering)

It is when I press the button in Jet1 (which triggers high speed in pump1) when I hear the humming noise for like 2 sec and the entire pump#1 shuts down for like 20-30 sec (I guess that is the thermal safety?). After those 30 sec, when heating is needed, the pump starts running in low no problem.

[CanadianSpaTech]

Is it just a hum or does it make a hard buzzing sound? You need to disconnect the pump from pack and test for power to both speeds. If you get correct power in both hi and low speeds problem is at pump. If you get power to both hi and low speeds at same time then problem is in the pack. A stuck relay sending power to both speeds at once. 

[Enrique]

Buzzing sounds, Ill take a video shortly (-20F today - so I may wait until it warms up a little)

Ill check the power thanks

I just replaced all the big relays on the board [previous issue with no heat].

Unless one has gone bad fairly quick (all replaced 3 months ago) or may be one of the small relays (small relays did not get replaced).

Will report back, thanks!

[Enrique]

Just double checking before I open the tub

4 wires to the pump: red/black/green/white

white= common

green= ground

red speed 1 , black speed 2 [or viceversa]

 

I should be reading in the pack (disconnecting the pump1)

Low speed: Voltage between red/black & white =220V black/red & white =0V
High speed: Voltage between black/red & white =220V red/black & white =0V

If I read 220V between red & white and black & white at the same time then it's probably a relay in the pack, right?

Or should I be reading red-green/black-green?

Thanks!