Here is a link that will clear things up
Check this court summary document to find out what went on when the sale of KA to WP was challenged by WCI and Magic Chef.
It will explain how ISE came to build the 20 series machines and then what was probably the 22 series and ended production with the 23 series derivative.
The post 20 series ISE's were nice looking machines with the sliding handle. I was told that it cost ISE $250,000 to rfedesign and impliment that handle system and when they finally stopped selling the machines, it was because WP was now building them and wanted too much for each unit.
The final series for them was a clone of the 213 series K/A's with the WP power module pump.
Ralph, the 20 series tank was the last of the full frame tanks, it had the hot air blower/dryer where the ISE's had the plastic blower and the water heat, drying element in the tank above the sump.
I have never seen a breakdown for the 20 derivative above, nor a parts breakdown. What was the actual model number anyway?
Most of the physical and mechanical parts like the door and panels and electical parts like the float and fill valve with sub into the newer machine, but the pump on the 20 was the unitdirectional pump motor with the drain solenoid, though I have to say I remember reading somewhere that they did have a limited number of them with reversing motors or at least motors with start relays. Not too sure on that. I am sure others here can verify that.
Your machine will clean very well regardless of the pump it has, thow I am much more partial to the Kitchenaid pump because of the real metal disposer in the pump. But the Powermodule is no slouch.
Check the link and see what it says. I thought it was an interesting read.