Hi guys, my Potterton Prima 40b Open Vent has started making a droning noise, this only started after British Gas did their annual service (The guy seemed to have problems putting the bits back inside the boiler... could that cause the noise?) It only happens after about 30minutes and is intermittent when the boiler fires, when the pumps running and the boiler has stopped heating, the noise stops...
Anyway they came back and replaced the pump head as it could be the bearing (which hasn't fixed the problem) they now said its sludge as the system is "incredibly dirty"
The pump (Grundfos) is above the boiler, when he opened up the drain the water was clear, when he removed the pump head black water came out, the system has Fernox F1 in the system, and the radiators get "bouncing hot" all over with no cold spots as British gas engineers describe it,
The engineer was very quick to quote the £800 flush and offer me finance on it, to a point he had his phone out to ring to arrange the credit!
My question is do most pumps have a bit of black water in the bottom of them, (the pump was approx. 20 years old) or is my system knackered as British Gas would like me to believe
Anyway they came back and replaced the pump head as it could be the bearing (which hasn't fixed the problem) they now said its sludge as the system is "incredibly dirty"
The pump (Grundfos) is above the boiler, when he opened up the drain the water was clear, when he removed the pump head black water came out, the system has Fernox F1 in the system, and the radiators get "bouncing hot" all over with no cold spots as British gas engineers describe it,
The engineer was very quick to quote the £800 flush and offer me finance on it, to a point he had his phone out to ring to arrange the credit!
My question is do most pumps have a bit of black water in the bottom of them, (the pump was approx. 20 years old) or is my system knackered as British Gas would like me to believe