Vokera Excel 80SP - What's in a Full Service ?

[WhatNext]

Hi

I believe that need to have my Vokera Excel 80SP combi boiler serviced.

It is providing plenty of hot water and the central heating is fine, it is just that after a period of not being used ( i.e. through the night ) it makes a brief loud mechanical notice whereupon the pressure gauge drops to zero just for a second and after this it is fine for the rest of the day.

I actually swapped out the circulating pump for a brand new pump, but this did not solve the problem.

I have since read on this forum that I need to have it fully serviced.

In the past I have watched the boiler being serviced and it seemed that it was just a matter of brushing the main heat exchanger coil, inside the combustion chamber, then hoovering out the dirt and dead flies, before re-checking the gas settings. I may be doing the engineer an injustice, but he did say that these older boilers are best left alone as far as possible.

I know that a servicing kit ( Vokera T0019 ) is available, but I have never seen it being used. What I have seen is the main diaphragm being replaced at every service.

Can any one advise what should happen during a full service on this particular boiler ? I just want to make sure that I have it fully serviced in the hope that this will resolved the problem.

Thanks in advance.

 

[ianmcd]

sounds like the primary flow switch diaphragm housing is blocked , a very small port in there is prone to blocking and what happens is when there is no demand the fan stops rather than going to slow speed, the pilot then causes a build up of steam in the heat exchanger, and then when there is a demand this is the noise you are hearing when the pump pushes cold water into the overheated heat exchanger, have a look at the fan it should never stop running unless you cut the power or switch the boiler off, it should run at slow speed when the boiler is at rest

 

[WhatNext]

Hi Ianmcd

I think that you could be spot on ! When I first switched on the boiler ( after changing the pump ) I do remember hearing the fan running on the slow speed, but I just had a listen now and I do not think that I can hear it.

Would this be sorted as part of a full service ? Is there any risk in using the boiler between now and the service ?

Cheers

 

[ianmcd]

yes get it sorted as soon as , it is not part of a standard service so make sure you mention it and try and find someone that knows the boiler, the build up of heat will cause the washers in the heat exchanger connections to become very brittle and will leak, where in the Uk are you ? someone from here might be near you

 

[WhatNext]

Hi I am in Aberdeen

 

[ianmcd]

PM a lad on here @McCombi he will sort you out

 

[WhatNext]

Ian you are a star many thanks