We recently bought a house with an existing spa. As far as controls go, there are three switches on the wall. One for the filter pump, one for the air pump, and the last one turns the gas heater on and off. None on the spa itself.

Below the switches is a black box that says SPA-TEMP RAMCO 1980.

The previous owner said that it didnt work and his pool guy didnt know what was going on with it.

I havent been able to find anything useful about it on the internet. Can anyone tell me what it is supposed to do? Is it repairable or is there a better replacement?

Thanks
wb