Hi everybody. This is my first time here on this forum, sorry for my bad English.
We have a Worcester Bosch 40cdi Combi condensing boiler, its about 5 years old. Our problem started yesterday. Temperature goes up very quickly to 90 degrees and after this gives some noise and display shows error U9...U8.......U1 ..U0. I was sure there was no circulation. I loosen a big silver screw on circulation pump to bleed it, but there was no air in it at all. So I have taken the screw out to see if the pump inside is dirty or blocked. We put a screwdriver inside the pump and I moved it around easily both ways, which ment that the pump was not blocked and the water was clean. We checked with a tester that the power 240V was on the pump terminals. When I switched the boiler on I saw that the internal part of the pump did not rotate when it supposed to. The fan and the burner works OK and the preassure guage show 1.5Bar. I was pretty sure that the pump was faulty.
We left the boiler off overnight.
This morning the boiler was cold, we switched it on and we noticed that there was a tiny leak (few drops of water) above the heat exchanger. After a seconds when the temp reached 90 degrees, the leak dried very quickly and I didnt know where the leak was comming from.
Yesterday I was sure that it was the pump was broken, but today I have thoughts that the boiler electronic system detected some faults in heat exchanger and does not let the pump to run.. ( can this be true ? or am I wrong?) .. Temperature goes up quickly only when we have both hot water and central heating system on. When we switch off the CH the hot water works ok. Room termostats are on at 25 degrees.
Can anyone help please? we have a baby and it is very cold at home..
Chris
We have a Worcester Bosch 40cdi Combi condensing boiler, its about 5 years old. Our problem started yesterday. Temperature goes up very quickly to 90 degrees and after this gives some noise and display shows error U9...U8.......U1 ..U0. I was sure there was no circulation. I loosen a big silver screw on circulation pump to bleed it, but there was no air in it at all. So I have taken the screw out to see if the pump inside is dirty or blocked. We put a screwdriver inside the pump and I moved it around easily both ways, which ment that the pump was not blocked and the water was clean. We checked with a tester that the power 240V was on the pump terminals. When I switched the boiler on I saw that the internal part of the pump did not rotate when it supposed to. The fan and the burner works OK and the preassure guage show 1.5Bar. I was pretty sure that the pump was faulty.
We left the boiler off overnight.
This morning the boiler was cold, we switched it on and we noticed that there was a tiny leak (few drops of water) above the heat exchanger. After a seconds when the temp reached 90 degrees, the leak dried very quickly and I didnt know where the leak was comming from.
Yesterday I was sure that it was the pump was broken, but today I have thoughts that the boiler electronic system detected some faults in heat exchanger and does not let the pump to run.. ( can this be true ? or am I wrong?) .. Temperature goes up quickly only when we have both hot water and central heating system on. When we switch off the CH the hot water works ok. Room termostats are on at 25 degrees.
Can anyone help please? we have a baby and it is very cold at home..
Chris
