My parents have had this spa for 20 years used it twice maybe three times the heater core blew and they never used it again . My father died two years ago and my mother left the spa. I purchased a new heater and installed it . My question is is there some kind of prep I should do be fore I turn this on ? OR should I just fill it and run it and see what happens..

Any help would be greatful.
Mr Crowley

What would the best way to hook up the ground for this I was thinking a saparate ground from the tub to a ground bar outside OR a ground wire to the water main in celler. Could I use a cloths dryer plug for this ? I believe they are 240 volt rated and 50 or 60 amps.

You need to install it according to code.

A dryer plug is not, and they're not rated that high anyway.

Check the voltage/current ratings on the control panel and consult an electrician if necessary. Depending upon control type, you may or may not need a neutral. In all cases you will need a ground (WITH the main power line connected at your mains box), AND a ground fault circuit breaker correctly installed.

You are correct there are only rated to 30 amps I need 50 amps I hooked up my 230 volt direct line and it works great.Made separate ground to the water main pipe.