toilet tank

Replace or repair the fill valve. It is locking up and not letting water into the tank.: My guest bath toilet tank only fill promptly sometimes, other times it seems to take an hour before if : fills again. When the other bathroom works just fine. It doesnt seem to matter if I am using water in any : other part of the house. Where do I look first for my problem.

: My guest bath toilet tank only fill promptly sometimes, other times it seems to take an hour before if : fills again. When the other bathroom works just fine. It doesnt seem to matter if I am using water in any : other part of the house. Where do I look first for my problem.Hi this could be accounted for the following 1- The fill Valve (Ball cock) could have sediment build up or a bad diaphram (washer) 2-The supply valve on the left hand side of the tank ( Normally unless it is a tile stop)could have a lose bibb washer which changes position sporadically and cuts off the full flow ( volume) to this fixture. 3- you could have calcium deposits on the inside walls of your supply piping restricting the flow.The simplest test would be to check the CW pressure/volume at the sink.With the aerator removed. if the pressure and volume are ok then shut off the water supply to the ball cock and disassemble then FLUSH carefully. Depending on which brand you have. POINT OF INFORMATION if you do decide to replace this device get only one with an approved Vacuum breaker as part of it.You dont want non potable water entering your system due to back syphonage good Luck.. Sylvan