What size Fernco coupling

This past weekend we had a break in a water line outside of the home. The line was repaired, when water flowed back into the house we experienced two problems. The tankless hot water heater quit heating and the master bathroom lost water pressure on the cold water side only. We are working with the water heater company to try to resolve the heater issue. I am assuming that some debris got into the water line and has clogged the cold water line somewhere between the hall bathroom and the master bathroom as the cold water works fine up to that point. The toilet, sink and bathtub have only a trickle on the cold water side in the master bath. Hot water side has plenty of water it's just not hot. How do I go about clearing the line to the master bath? I have a slab foundation.

Hi,...can someone recommend a quality manufacturer of hose bibbs...or a quality plumbing supplier in general? I want something that will last more than a month or two...thanks