Keston Celcius 25 HW fault causing vibrations

[bigmike69]

Boiler recently serviced, has never had any issues. 5 years old. With hot water tank. Have recently bled all radiators.

It comes on three times during the day for 30 mins each. temperature setting on boiler is half way.

Since the last service it sparks up fine but makes these terrible vibration sounds 5 or 10 minutes into the cycle. At the same time you can hear alot of water flow in the boiler.

At this time the water flow LED (RED) flashes fast (5Hz).

The manual states in fault finding 5.1 that this means:

If this occurs consideration should be given to regulating valves on the system to restrict system flow rates

Can anyone recommend how I can go about actioning this? Many thanks in advance.


Descritpion of fault finding below:

http://www.keston.co.uk/assets/pdf/Discontinued/Celsius-25-manual.pdf

(5) The boiler will automatically and continuously adjust its power output and pump speed to best match the demands of the system at any time. In the event the boilers integral pump cannot maintain sufficient boiler water flow to disperse the heat generated the red pump LED will flash slowly (1Hz). If this occurs any system restriction should be cleared. If this persists due to an abnormally high system resistance consideration should be given to an additional system pump. In the event the boilers integral pump cannot reduce the water circulation to ensure the most efficient transfer of heat to the system water the red pump LED will flash rapidly (5Hz). If this occurs consideration should be given to regulating valves on the system to restrict system flow rates

 

[Boilerman2]

After bleeding the radiators did you locate the system filling loop and reset the system pressure to 1-00 Bar?? I suspect you have a shortage of water in the system which is effecting circulation

 

[bigmike69]

Hi There, good suggestion, but yes I did check the pressure and it was still at 1.5, it didn't change...

I spoke to keston today who suggested the following:

- there mau be air inside the boiler? autoairvent sticking? problem with water (flow?) pressure? blockage behind diaphram.

not too sure which ones to check if I can check myself

 

[Boilerman2]

Sadly neither can be checked without removing the combustion cover so its a job for a RGI

 

[bigmike69]

I will need to call them back in, thanks for your help.

 

[Boilerman2]

U R very welcome!!

 

[Agile]

Hi There, good suggestion, but yes I did check the pressure and it was still at 1.5, it didn't change...

After bleeding rads the pressure should reduce!

Did you ever consider that the gauge might be stuck ?

Suppose you add a little water and watch the gauge go up ( or not ! ) ?

Tony

 

[bigmike69]

Yes, I topped it up a little to ensure the needle moved and it did the boiler fuse blew yesterday, not sure if it is related to this or not, which I replaced with another 13A fuse.

Still giving the vibration noises and negotiating with the people who serviced it to get them back round to do the job properly this time.

 

[OLLIE20]

Absaloutly awful awful awful boiler, doesnt help with your fault but thought i would let you know, also make sure your twin flue is MUPVC and not PVC like loads

 

[ChrisR]

Don't use 13 A fuses. Check the manual, they're usually 3A sometimes 5A.

 

[bigmike69]

I know it's not the best boiler but it came with the property and is only 5 years old and has never before had any issues until it was 'serviced'.

it had a 13a fuse in there, so replaced like for like. i checked the manual and looks like you are right - 3A!

everything works and it heats ok, apart from this vibrations sound and feel midway through cycle. it then just starts up and works / heats normally again. i can feel air pumping in and out of the outer boiler case when it does the vibration noise.

 

[mickyg]

There's something badly wrong if it's blowing 13A fuses. You should get professional help - to install a Viessmann boiler - with weather compensation, naturally!

]
tit

 

[bigmike69]

this turned out to be a gas valve adjustment issue and when the boiler was on low, once this was adjusted (not enough gas coming through) the issue went away and it is functioning ok. not before numerous parts replaced!