Whilst above ground spas, or hot-tubs, provide a quick and convenient start to owning a spa, having an in-ground spa will really add to the value and appearance of your property. If you’re reasonably confident and competent with plumbing techniques there’s no reason at all why you can’t install the plumbing for an in-ground spa yourself.
It might seem obvious but the first point here is to make sure when you’re excavating the pit in the ground for the spa to go in to – you also need to excavate trenches for the pipe work to and from it. In essence this means trenches to the appropriate depths as marked on the shell of the spa when it was being manufactured.
The pipe-work marks will also invariably be marked with what should be run to where. eg. These may include: the spa filter and bottom drain, a return line from the pump to the spa jets, a booster pump leading to the bottom drain, lines connecting other spa jets to back to the pump and, if fitted, a pipe to connect the Ozonator unit to the spa.
You will also see markings for the spa water temperature sensor and an air-blower line. Where connectors or ‘elbows’ are required in the pipe-work, try and only use 450 ones; as they’ll help maintain the water pressure at the spa jets compared to 900 ones.
Above Ground Units and Inground Spas
Above the ground and ideally not more than around 30 feet from the in-ground spa itself, will be the plumbing units required to operate the in-ground spa. These units will vary according to the make and model of the in-ground spa you purchased. Basically you will have been offered two options when buying the hot-tub; either to purchase a portable setup or a fixed/commercial one.
Whichever you chose will include the following components which need connecting as described below. NB. You do not need to plumb an in-ground spa to the mains water supply. Filling the spa can be done with a hose-pipe; the water can then be constantly re-cycled for anything up to 4 months by a highly efficient filtering system.
Plumbing an In-ground Portable Spa System
Whilst taking up less space these units are invariably not as efficient or cost-effective as commercial ones. One major draw-back with them is that the water pump, air-blower and water heater will all be in one unit, making maintenance and repairs more difficult. However, if this is the system you have; the pipe returning water from the bottom of the spa needs fitting into the pump, which may well be a two-speed pump.
From the pump the water flow needs to enter the heater and then on to the filter unit, before flowing back to the ring of pipe-work around the spa. That ring of water pipes will meet with the ring of air pipes, which are fed air under pressure from the air blower. Don’t forget to include an ‘air check’ valve in the air flow pipe-work.
Commercial Spa System
While the basic arrangement of the pipe-work is exactly the same as described above; a commercial system will have separate units for the two-speed pump, heater and air blower. Furthermore, the heater will be more efficient and sophisticated, meaning that it’s not solely reliant on electricity and will heat the water in the spa in a fraction of the time required by a ‘portable’ heater.
Even better, if the climate where you live is suitable you could at least complement the water heating system with a solar powered one. A commercial system will also probably have a mineral based filtering system rather than a cartridge one, giving it a longer and more efficient life.
See Also: Different Styles of Spas