This is an excerpt from the Spa Pool manual.
There may come a time when you need to leave the spa for a period longer than a month and want to shut the spa pool off. Follow these steps to safely prepare the spa pool for hibernation:
1. See Previous Steps
Perform steps 1 to 3 from ‘Leaving the spa short term’ before moving on.
2. Turn OFF Spa Pool
Completely turn off the spa pool at your isolation switch or mains board.
3. Drain the Water
Drain the water out of the spa via the main drain valve.
4. Drain pipes via Barrel Unions
Open up the cabinets surrounding the spa and locate the barrel unions at the controller unit and the pumps. Loosen (strop wrench may be required) the barrel unions either side of the component to drain excess water from the surrounding pipes. Put down a towel if required to soak up water. Tighten the unions back up once finished.
5. Blowout Pipes (Recommended if switching off for 3+ months)
Using a shop-vac, set to the blow function instead of suction and climb inside the spa pool. Go around the spa and unscrew each jet as you go, place the vac onto the jet hole and turn on - this should force water out through the intake valves at the bottom of the spa pool, removing excess water from the pipes.
6. Wipe Down Spa
Remove any excess build up of water from inside the spa and wipe the acrylic shell down completely with a micro fibre cloth.
7. Secure Cover
Place the spa pool cover on securely and lock with clips. Cover entire spa with a tarp or ‘spa winter cover’ for best long-term protection.