I have an Essence 345 hot tub with dedicated 220V and a Balboa R574 controller board. The motor has burned out due to power outages during winter and I want to replace it with a heavier duty motor with a start capacitor. Ideally I would upgrade the 115V motor to a 220V motor with heavier gauge windings, but I can't find a schematic for the R574 controller that can tell me if I can drive a 220V motor from this controller board.

Does anyone have a schematic for the R574 Balboa controller?
Does anyone have experience upgrading this configuration to a 220V motor?

There is nothing to upgrade.

Simply pull the white wire from the motor plug and attach it to L2 (red).

Now you can run a 230v pump.

Thanks for the response, although I don't fully understand it. The white wire is the common. Red is high speed on the motor wiring.

Can you elaborate what you mean by pull the white wire and attach to L2 red? I assume this would make it a one-speed pump as opposed to the two-speed option.

White is connected Neutral now. It is the pump common.

Black/Red is connected to L1 to energize the pump motor either high or low speed @ 115v.

Connecting the common (white) to L2 instead of neutral makes it a 230v circuit.
It will still be a two speed circuit.

So currently I have:
white = common
black = L1 (low speed)
red = L2 (high speed)

The 230V circuit would be:
common = open
L1 = black and red
L2 = white

I'm assuming I need red connected to L1 to ensure high speed operation. Is that correct? I wired it up standard at 110V and the motor runs in both speeds fine, but I'm assuming it is running slower than the expected speed.

Again, thanks for the help.

NO.
L1 and L2 are Black and Red coming into your box from your main power source.

PUMP PLUG NOW 115V:
White = Common: Neutral (WHITE MAIN POWER INPUT LEAD)
Black = Low Speed: Controlled by relays on board
Red = High Speed: Controlled by relays on board

PUMP PLUG MODIFIED 230V:
White = Common: L2 (RED MAIN POWER INPUT LEAD)
Black = Low Speed: Controlled by relays on board
Red = High Speed: Controlled by relays on board

Got it. Thanks.