Yes it looks like a microchip part made specially for the output module. It's probably a pre-programmed PIC. If it is bad, I think your only hope is another from the manufacturer. By the way, your R15 is missing. Did it fall off or intentionally left off by the manufacturer?
The label "Version 1.0" indicates it is a programmable part, not simply a comparator.
You have 8 output transistors and an 8 pin connector. Not enough pins to drive 8 transistors plus supply power. I assume the controller is a kind of serial-parallel converter.
What makes you think this chip is the culprit?
Thanks Harald, it was giving erroneous error faults and doing strange things like not turning on or off zones, and turning on multiple zones at once.
One time it was briefly flashing on/off a zone about every second.
All discrete components tested good.
I switched this out with another module and it has been working flawlessly for over a month now.
That tells me the problem is with U1.
Your correct, I misread the routing of the traces.
The gates of all 8 triacs goes through a blocking diode and through a 220Ω resistor and then to output pins of U1.
So yes, its likely serial com on the pins to give commands to turn on all 8 outputs as well as monitoring the voltage drop on all 8 to give either open circuit faults, or overload circuit faults.
Alas, this is another failed repair because of not being able to ID and procure a replacement part.