MiniMax Plus
by Pentair

 H2Oco.com

Note
Some models of the MiniMax Plus used different temperature control circuits. These versions appear in the 1990's when the heater went by the name 'Purex'.
These can be identified by the 4 red diagnostic lights located above the temperature controls on the front of the heater. Look under the 'Not Shown' section below if the part does not appear in the breakdown.
 

Breakdown shows the Control Circuit of the Electronic IID Model

           

 Note 'A'  - example - Model 300 requires 5 regular burners and 1 burner with pilot bracket
 
 Note 'B'  - Call for orifice size to order - size depends on altitude.
( Note - orifices for altitudes of 3000 to 5999 feet is Pentair's part number 472569 )
 
 Note 'C'  - Burner trays shipped complete are shipped with burner orifices which are for altitudes 0 to 2999 ft.
For other altitudes,  you must order the orifices separately and install them in the new burner tray.
( Note - orifices for altitudes of 3000 to 5999 feet is Pentair's part number 472569 )
   
 Note 'D'  - In January 1996, the circuit boards for Minimax Heaters were changed at the terminals. If you have a heater manufactured before January 1, 1996 and you receive a newer circuit board with the smaller terminals and the older thermistor has larger connectors, the larger connectors can be crimped so they will fit tight on the newer circuit board terminals.