Answer:
I suppose that when Dobry and Chet's entered a contract there was a time set for the reparations to begin, maybe not to end the repairs since that may vary, but at least to start working on them and try to do it fast.
If Chet's delayed their work and did not start repairing Dobry's equipment on time (5 days), then Dobry should be able to sue for consequential damages in order to recover money due to a foreseeable loss beyond the contract. If Dobry cannot operate its equipment then it cannot produce, so it is Chet's fault that their production is halted.