Raven ****e csi 85b(T) overheating

[Adrian80]

Hi Guys,

I realise i have posted this before, but i didnt get any replies, so hopefullly someone out there might have a suggestion.

had a new boiler fitted csi 85b(T), the thing is it keeps cutting out.
The overheating flame failure light comes on. I am completely stuck to what to do..

the system has on radiator with a normal radiator valve so the system is circulating ok, i have also taken off one of the thermostats off the biggest radiator so there should be loads of circulation.

But the thing keeps cutting out.

It also cuts out after having a hot shower ???

if we dial the thermostats on the ch and water right down then its doesnt but then again there is no bloody heat.

Any one got any suggestions.....

Cheers
Adrian

 

[Aquaheat]

Hi,

Assuming that there is circulation and the boiler itself isn't really overheating ,but is just cutting out as and when it wants, then the normal cause is faulty thermisters breaking down and telling the boiler to lockout.

 

[gas_man_gaz]

id agree, the thermistors can be really problematic

 

[gas4you]

If it has just been fitted, what does your installer say about it and why haven't Ravenheat been called in under warranty?

 

[Adrian80]

Cheers guys for all the responses,

Difficult to get hold of the installer, and get him to get onto raven heat.

Many thanks
Adrian

 

[gas4you]

Contact Ravenheat yourself then

 

[gas_man_gaz]

how old is the boiler?

 

[Slugbabydotcom]

A new boiler will have a clip on CH thermistor.
If some corrosion got to the sensor part before it was covered in thermal grease it might not sense the pipe properly.
Unclip the sensor and rub the contact part of it with a coarse cloth to clean it. Wipe the thermal paste on the pipe to a thin smear and save a thin smears worth for terminal you just cleaned. Put it back on and see how it goes.
I have fitted a new Ravenheat with a faulty sensor in the past and they sent me a new one in the post which sorted the job out.
Fan modulation boards cause more problems than thermistors on later Ravenheats.
Give them a ring on 0113 252 7007 and make sure you have your serial number handy. Its on the cardboard box, on a sticker facing you on the left hand side when the front cover is removed and on a data sticker at the bottom right hand side INSIDE the back frame [mission impossible]

 

[Agile]

Have the CORGI number of the installer ready in case its not been registered with them.

I do hope he completed the Benchmark Certificate.

What kind of a service does anyone provide who is "difficult to get hold of". Why not name and shame so that others are not encouraged to let him fit boilers for them and then he becomes uncontactable when anything goes wrong!

Tony

 

[Adrian80]

Cheers guys for all your helpful suggestions, I will make sure i prepare the serial number etc before calling them.

i will let you all know how it all goes..

Cheers once again,

Ad

 

[Adrian80]

Hi to close this one off,

The raven heat engineer came round and the replaced a flu reducing ring around the flu, reduced the size from 79 to 77mm, and now its working. Apparently wasn't creating enough -ve pressure for the air switch to click on.

So the fault was a flame failure rather than over heat.

A small piece of metal tape crossing one half of the reducing ring would have work apparently. However the boiler is working so far.....

Cheers guys.

the difference in area between the two was 49.01cm vs 46.5cm a grand total of 2.4cm2

good knows why they dont fit this one as standard....

 

[g20]

hmm strange, because surely it wouldn't have been able to ignite if the air pressure switch wasnt making?

 

[Adrian80]

Hi, like you i thought this couldnt make much difference, but the boiler would ignite when cool, then as it warmed up it failed to ignite.

The explanation was as the thing gets hot, the density of the air in the flue was less and then, as you say, the switch wouldnt make...

wait and see....

as they say the proof is in the pudding. ill post again in a couple of weeks if its still working....

 

[Agile]

Did you check the installation instructions to see which restrictor ring should have been fitted for your particular flue length?

Tony

 

[Adrian80]

Dear all,

The restrictor ring seems to be working, on the boiler comes on and off just fine..

Tony, no mention in the instruction of a restrictor ring, and flu fixing, but it makes complete sense if the flu was longer then this ring might not be necessary, However it cant imagine this situation is uncommon.

My boiler is mounted on an outside wall, the flue is probably just less than 1m.

all seems to be working fine..

Cheers
Adrian