Hello all,

I have an older Gatsby spa which I have replumbed and 2 years ago replaced the electrical items with a Nu-Wave NU1000 Spa Pack. The pack is a convertible and was originally setup and used in 110v mode. I've since added 220 volts to the spa area hooked to a 50amp circuit breaker so the heater would be more efficient and heat in both high and low speed modes. I've moved the jumpers around on the inside of the box - moved the selector switch from 20/30 amp to 50 amp service. I also purchased a new spa pump - 220v 3hp 2 speeds.

My problem is the motor does not appear to run at full speed (even at low speed). If I increase the thermostat to make the pump and heater kick on, the lo-speed and heater lights come on, but it's at a reduced speed (or so it appears to me). After about 2 minutes, the pump kicks off and is very hot to the touch and it will not restart until it has cooled down. The label does say it is thermally protected - so I'm assuming it is protecting itself from something... Also in high-speed mode, the pump cycles on and off - I've not left it that way more than about 15 seconds for fear of damaging a brand new pump.

I've double checked my wiring and have 110v on the two hot wires and my neutral wire is connected to a known good neutral bar. My ground wire is connected to the same ground posts as other breakers in the box and is the wire I'm using to verify voltage on the 2 hot wires.

I'm stumped - I'm hoping this is something simple and doesn't mean my brand new pump has an issue. Anyone have any ideas?

ok - it seems as though even though the spa pack is convertible from 110 to 220 - the pump still needs 110v to run. So I have a brand new 220 volt pump which I apparently cannot use....

you are right, changing from 120 to 240 only enhances your heating, your pump still stays the same. However you could get around this by jumping your L2 on the 240V pump to L2 on the line side, instead of using the neutral from the old pump. That would bring you to a 240V pump setup, as the switched side would still operate normally.

That would be great to be able to use the new pump! So, just to make sure I'm clear - I currently have 4 wires going to the pump - ground, neutral, and 2 hot wires (L1 and L2). Are you saying to remove the neutral wire and connect the L2 wire to the neutral location? Will I still have 2 speeds? The tub uses the low speed to circulate when in heat only mode. Thanks for your assistance!

I'm referring L2 to the line.. the pump has L1 and L2 and those are for low and high speeds. You keep those the same as the 120V pump. Instead of using the Neutral, you hook the neutral for the pump to the L2 of the Line feeding the circuit board. Typically you have a black, red, white, and green feeding a 120V spa, with black being high speed and on L1, and red being low speed and being on L2. Those stay just like that. The only thing you are doing is replacing the neutral with the other side of the 240V.

In fact you may even be able to move that white wire for the 120V pump in the control cabinet to a terminal on the circuit board that supplies the other half of the 240. Right now it is probably tapped into a cluster of terminals for neutral. Use a volt meter to determine if you can do this. Simply place on lead on the low speed motor output, turn on the low speed of the pump, and use the other test lead to probe available terminals on the board until the meter reads the 240. Many circuit boards have a cluster of terminals for taps, and you can just tap right in.

Just wanted to add that many 240V pumps use a common, instead of neutral, so look for this.