Hot Tub Pump tries to start, then shuts down after 3 seconds

[massimofinance]

Hello all- I replaced the seal in this pump last winter. Now, it tries to start, runs/hums for 3 seconds, I hear a click in the electronic box, and it shuts off. This is pump 1, which is the one that circulates while the tub is not being used. Is the pump seized? I tried to hit it gently with a hammer, it did not fix it. Any help is greatly appreciated!

 

[ondarvr]

Most likely a bearing is bad, but it can also be some junk in the impeller. If an older pump sits for a long period of time it may have a hard time spinning the first time if the bearings are in poor condition. If you can get to the motor, you can pull the cover off the back and turn the shaft with a wrench to see if it's tight or turns smooth. If every thing moves easily the capacitor could be bad. Turn off the power when you take the cover off, the wires in there can be hot.

 

[MTboatguy]

Sounds like the start cap is going bad.

 

[bigdee]

My bet is the motor is seized because of water getting into front bearing. Common problem with pool pumps. Like ondarvr said pull rear cover of motor and rotate shaft back and forth a few times to free it up. I usually have to do this every season with my pool pump.

 

[thumpar]

If you have 2 pumps try switching the connectors at the box and see if the problem follows the pump. That would rule out the box itself. If the pump is for sure the problem I would take it apart and figure out what is not working. I had a blower that had bad brushes. Every place I called told me I just had to replace the whole blower. I was able to cross reference them for a cheap fix.

 

[Bob_VT]

Is this the first use of the motor? I had that problem in the past and it was air on the lines. I cracked the connections open and it let the air escape..... back to normal. It only takes a tiny air pocket

 

[gm280]

Sure sounds like a stuck rotor. If you can get it moving, it may need nothing. But I would most certainly service it if it were mine. Sounds like the starting capacitor is working but the run capacitor isn't kicking in. And that is because the motor isn't turning up. JMHO!

 

[bigdee]

Sure sounds like a stuck rotor. If you can get it moving, it may need nothing. But I would most certainly service it if it were mine. Sounds like the starting capacitor is working but the run capacitor isn't kicking in. And that is because the motor isn't turning up. JMHO!

Yes I agree it most likely is stuck. Split phase pump motors have a centrifigul switch, run capacitor but no start capacitor. Contact on centrifigul switch could also be dirty.

 

[gm280]

Yes I agree it most likely is stuck. Split phase pump motors have a centrifigul switch, run capacitor but no start capacitor. Contact on centrifigul switch could also be dirty.

Yes I was thinking the switch as well. That is probably the clicking noise.

 

[massimofinance]

Thank you all. This is not the first time I have started it, it has been running for 6 months or so since I replaced the impeller seal. Maybe I did a bad job there and water got in? I looked at the end where there is a small plastic cap (opposite where the tubes/impeller are) and see the shaft spinning very quickly. The problem is when I try to turn that pump on at the top side control, it buzzes loudly for 3 seconds, then shuts itself off and the shaft stops spinning. Based on what I am reading above, the contacts on the centrifugal switch might be dirty. Do I need to remove the pump from the spa in order to service that switch? Also, any advice on that? I can also try to switch the pumps at the control board to rule out any issues in there. thanks...

 

[gm280]

Thank you all. This is not the first time I have started it, it has been running for 6 months or so since I replaced the impeller seal. Maybe I did a bad job there and water got in? I looked at the end where there is a small plastic cap (opposite where the tubes/impeller are) and see the shaft spinning very quickly. The problem is when I try to turn that pump on at the top side control, it buzzes loudly for 3 seconds, then shuts itself off and the shaft stops spinning. Based on what I am reading above, the contacts on the centrifugal switch might be dirty. Do I need to remove the pump from the spa in order to service that switch? Also, any advice on that? I can also try to switch the pumps at the control board to rule out any issues in there. thanks...

If you own a good meter, you can check to verify the proper voltages are reaching the motor as a first thing to test. If there is missing a leg, it will not run. JMHO!

 

[massimofinance]

If you have 2 pumps try switching the connectors at the box and see if the problem follows the pump. That would rule out the box itself. If the pump is for sure the problem I would take it apart and figure out what is not working. I had a blower that had bad brushes. Every place I called told me I just had to replace the whole blower. I was able to cross reference them for a cheap fix.

I wanted to try Thumpar's advice to switch the pump connectors at the box and did that. Weird thing is now both pumps work fine. While a good result I think, I still do not understand what happened and what more I should do? Thanks.

 

[ondarvr]

Let's get on the same page here. You said the shaft is spinning, but when you turn it on it hums, then shuts off. So I'm understanding this is a two speed pump and it appears to be working on low speed, but pushing the button for high speed trips the breaker. Is that correct?

 

[ondarvr]

Your new post and mine happened at about the same time, so is it fixed? Do you have a single speed pump and a two speed pump, if you do, by switching them you may have two single speed pumps now.

 

[Johnstar]

I can relate to the hammer tactic. Ever since I've had a hot tub, it does nothing but consume money and occasionally help me relax when it's in working order.

 

[massimofinance]

ondarvr, thanks. the pump that was not running was pump one and I think it was a two speed pump. This is the one that will turn on by itself to keep the water moving. the other pump was a one speed pump. SO, I am thinking I didnt fix anything and by attaching the two speed pump to where the one speed pump was, it wont circulate by itself. confused why the circulate mode (speed one?) works but when I turn it on (speed two it doesnt and now when I turn it on it works. weird.

 

[ondarvr]

On low the two speed pump runs to filter and heat the water, depending on how it's wired (110 or 220) or if it's a gas heater, that pump needs to run on that circuit to keep things working. Either circuit or pump will move water, but only the two speed pump circuit will filter and heat.

There could be a short in the switch or pump, maybe even a weak breaker.

 

[thumpar]

The test suggestion was to rule out a seized pump. Now we know that both pumps will run. Did you try switching them back to see if the problem is the same as before?

 

[massimofinance]

thanks thumpar, I switched them back and I still have the same problem. The two stage pump only runs on the low filtering stage when hooked up to the pump one plug on the board. Weird it runs fine in the second (powerful) stage when I activate pump two (when it is plugged in as pump two on the board). I am confused as to what this means? Is there a problem with the capacitor? THX.

 

[ondarvr]

Sounds like a shorted switched or wire.