no hot water after trying to remove air lock

Trouble is.. you still have an air lock in the hot water side of the system? When drained down to clean cold water tank- REMEMBER - that also feeds the hot water tank too.!! You should have isolated the cold feed to the hot water tank 1st before removing it to clean it out? This would've safely plugged until you were ready to refill the CWSC (cold water storage cistern) for hot and cold outlets. If hot water is running intermittently - means there is still air within the system. Depending on pipework and layout this may be awkward to replenish Try using a wet vac.? Hope this helps. Pd

this is hard to do as sink mixers are bi flow water does not mix until after leaving spout,best done if you have a basin mixer as these mix within body of valve,if single taps on basin use a hose between the taps,sometimes squeezing washing up liquid into cold down service from tank to cylinder.