This boss hits like a truck...no.. more like a bullet train
You literally cannot keep yourself alive against this robot unless you cast Flash Heal 100% of the time, relying on their crits to slowly bring you up.
Mana is not a problem on this boss since every hit guarantees 10% of your mana back from Masochism. Therefore you can actually afford to spam yourself with Flash Heals while your dots slowly drains his health away.
The main strategy is simple: Survive. The berserk timer is irrelevant if you cannot survive. So the main thing is to do everything you can to improve survivability. PW:S glyph, Flash Heal Glyph are all vital against this monstrosity.
Once you can outheal his damage, even by a tiny amount, you can begin to spare GCDs to apply dots, and rely on those to slowly whittle his health down to 75%, the first heart phase. Once you reached this point, you're already more than halfway through the fight. Once the heart appears, BURN it as much as possible, while taking care of adds. Preferably get those 200k health robot adds down a little while into, if not before the robot recovers from his heart phase. Ignore the little repair bots and bomb adds until after the boss has recovered.
Once the boss has recovered and (preferably) the big 200k hp add is down, instead of sparing GCDs to dot up the boss, use those GCDs to burn the bomb bots, this should also simultaneously kill most if not all of the smaller repair adds.
After this point its a simple matter of repeating everything