I have a Grundfos UPS 15/50 Selectric pump. The pump is around 15 years old and is located in the upstairs airing cupboard along with the hot water tank. The boiler is traditional gas fired and is downstairs.
The pump has started to make a stange grinding noise - a bit like a hammer drill. It's intermittant, lasting for a few seconds at a time, and seems to occur most frequently in the morning when the hot water and central heating system fire up together but it has occurred at other times too.
Am I describing a dying pump or could it be something like air in the system? If the latter, how do I get the air out? If the former, how easy is it to replace the pump? It looks straightforward enough to do by closing off the gate valves on either side of the pump undoing the "nuts" attaching it to the pipework and swapping with another 15/50. Is it really that easy or should I call a plumber?
The pump has started to make a stange grinding noise - a bit like a hammer drill. It's intermittant, lasting for a few seconds at a time, and seems to occur most frequently in the morning when the hot water and central heating system fire up together but it has occurred at other times too.
Am I describing a dying pump or could it be something like air in the system? If the latter, how do I get the air out? If the former, how easy is it to replace the pump? It looks straightforward enough to do by closing off the gate valves on either side of the pump undoing the "nuts" attaching it to the pipework and swapping with another 15/50. Is it really that easy or should I call a plumber?
