The heater tube is always integral with the controller box, and this is called a spa pack. These units are flexible in where they can be located and how they can be oriented (horizontal. vertical, before the pump, after the pump, etc.) Connections are 2 inch, and that is standard. We can supply a 2" to 1-1/2" adapter if your piping is 1-1/2". Measure the outside diameter of your piping (not the connectors) and I can then tell you whether or not the piping in your tub is different over what it would be here.
What we can't satisfy is control of the 3-speed blower directly from the touch pad. The touch pad has a blower button, but this only turns the blower receptacle ( a 3-pin receptacle) on off. Unless the blower switches to the next speed, each time power is applied, you would have to decide which speed you wish have operational.
Another item that has to be clarified is whether indeed you have two identical 1 speed pumps. Typically with all modern hot tubs, the pump that circulates water through the heater, is a quiet circulation pump running at 1450 rpm. So either the tub would have a circulation pump and a higher power jet pump, or it would have one 2-speed pump that is used with the heater and also supplies some of the jets and a 2nd pump which supplies water to the other jets.
If you have either of those arrangement we could supply you with either a Balboa GS501Z retrofit kit or a Balboa BP1600 retrofit kit. Or if you indeed have two identical 1 speed pumps, then either a GS520SZ or a GL2000 retrofit kit would be required. The limitation regarding the blower applies to all. A retrofit kit comes with the top side control panel, a complete set of cables with the right connectors including one for the light and a comprehensive manual. All these models are suitable for 220-240v 50 Hz and all come equipped with a 3 kW heater element. The BP1600 and the GL2000 are higher end models and are capable of wireless remote control. The remote for the BP1600, if so equippedcan, would be a iPhone/ITouch/iPad.
Dieter Jung
Northern Lights Cedar Tubs Inc.