Very noisy when boiler starts up

[mbee123]

I have a conventional set up with a Baxi Solo and hot water tank (vented system)

When the boiler starts up (hot water only or central heating) there are loud noises coming from the pipes to/from the boiler

I have had lots of problems over the years, last plumber I had was convinced there was a build up inside the boiler but he flushed it out and said it was clear, he couldn't find a blockage/or any air, he spent a good 4 days on the system and couldn't resolve the issue and then would not take my calls, he has left me with an overide on the flow switch in the boiler

I am reluctant to drain the system as whenever I have I have had problems getting the system operational again

I have tried adjusting flow rate on the grundfos pump whcih temporarily helps but the issue returns

I get a small amoutn of air out of the highest radiator every month or so but nothing too much

Appreciate any help

 

[ianmcd]

Which Baxi Solo ? there are lots of them

 

[mbee123]

Hi, its a Solo 24 HE thanks

 

[ianmcd]

can you check to see if the pump is fitted on the flow or the return pipe, turn the boiler on and the flow should get hottest first, you say you are getting air problems, if this is the case then with your boiler the pump should only be fitted to the flow, for others reading this is for this boiler not every boiler

 

[mbee123]

Pipe goes into bottom of pump (inlet) then out of top (outlet) into 3 way valve
It was already warm , it's not easy to follow pipework as it disappears into floorboards but the other pioers I airing cupboard get warm after it runs

 

[mbee123]

Pipe goes into bottom of pump (inlet) then out of top (outlet ) into 3 way valve
These pipes already warm, when I start the pump other pipes in airing cupboard get warm, not easy to trace as they disappear into floorboards

 

[mbee123]

 

[mbee123]

Not sure if the pics or my rough diagram will help

 

[ianmcd]

No sorry your diagram makes no sense, wait untill the system is cold then turn it on and see of the pipe with the pump on is the first to get hot

 

[mbee123]

Yes the pipe with the pump on gets hot first thanks

 

[ianmcd]

he has left me with an overide on the flow switch in the boiler

Not sure what you mean by that , do you mean he has bridged out the flow switch ?

 

[mbee123]

Yeah, the two black wires are now connected together, see pic

 

[mbee123]

 

[ianmcd]

That can not be left like that, my advice is to turn off the boiler immediately, an engineer is permitted to by-pass a safety device while still on site and working on a boiler, but at no time can a safety device be left by-passed, you definately need a different engineer