Always reads hot

Hello I have a Blue Essence by hayward, ever since this fellow hooked up this unit it has never worked all it reads is "hot" I have a salt cell that just reads blue essence no t-cell # on it, I realize that I've been ripped off, the pool service that installed this has nothing and I do mean nothing but horrible reviews he refuses to answer my call or return one so I have given up on any help from him have a serial # of 2A21111- something somewhere in that number is suppose to be the month and year of manufactured if anyone knows this, what do I do generator always reads hot and has never worked not once, if I knew I was allowed I'd throw his name out there, but it's help I need first, can anyone help