Alpha CB50 - Help - before I take a hammer to it!!!

[lawrenso]

Hi Guys,

I don't know if you remember my last issue with this
Boiler exploded

Well, now it is on the blink again. Wife phoned me last week to say it was not working - flashing alternate A and B- Pressure low - got her to top it up - all OK until yesterday - When I ran out of hot water in the shower - did think that the pressure was low! - went downstairs and checked - flashing lights but pressure dial OK - Phoned BG - then had a look as I left for work - hey presto - no fault lights - boiler working so cancelled BG engineer (payment taken - over a week for refund )

Come home tonight to be told it had done it again and cleared itself again - this time the pressure had increased to up to 2bar - so I thought lets drain a bit off - done this to just inside the green - low and behold - fault lights flashing again.

What the hell can it be this time?? This boiler is driving us round the bend - only 5 years old and never had so much bother - even when we lived in a hard water area .

Any pointers/advice (except for the obvioius - bin it!!) - I am going to call BG but already made one payment this week so thought I would give here a try.

Cheers

Lawrenso[/url]

 

[gas4you]

Could be some crud in the pressure sensor giving the pcb wrong info.

Has the expansion vessel been checked for the correct pressure or water in it, if the pressure is rising too far when on?

 

[lawrenso]

Explansion vessel was done at Christmas when they fixed it. As for the pressure sensor - is this accessable to check - been an hour now and still flashing!!

thanks for the quick response

lawrenso

 

[gas4you]

Personally if I suspect a pressure sensor, I always replace instead of trying to clean.

Can't remember where it is on this boiler

 

[lawrenso]

Personally if I suspect a pressure sensor, I always replace instead of trying to clean.

Can't remember where it is on this boiler

Thanks - came yesterday (a day early!!) and sending somebody back today who has worked on our one before - methinks they are scared of it

God knows - I am fed up of it!!!

lawrenso

 

[Agile]

To me most of your issues are very minor in engineering terms!

I have seen a new expansion vessel fitted by BG where they did not set the air pressure to the right value and of course it continued to drip from the PRV.

The landlord called me and I sorted it all out and cleaned the system as BG wanted that done ( or rather wanted to charge £600 to do it themselves ). It was small microbore system in a modern one up one down house. As all the rads were warming I just used a chemical clean for £180.

Tony

 

[lawrenso]

To me most of your issues are very minor in engineering terms!

I have seen a new expansion vessel fitted by BG where they did not set the air pressure to the right value and of course it continued to drip from the PRV.

The landlord called me and I sorted it all out and cleaned the system as BG wanted that done ( or rather wanted to charge £600 to do it themselves ). It was small microbore system in a modern one up one down house. As all the rads were warming I just used a chemical clean for £180.

Tony

Hi Tony,

we have had a whole list of issues with the boiler - the worst (as such - dec 27th - subzero in the daytime - it was personally bad even though it was a frozen overflow pipe). I go away a lot for work - both in the UK and abroad, and my wife is as technical as a rock and has no confidence in the boiler.

It has been fixed now - pig of a job for the engineer - flow sensor as Gas4you diagnosed (thanks) - the problem was getting the fiber washer out that was seated 2cm in the housing - had to take the pump out to get to it to get it out.

Also - water had a lot of bits in it - he suggested MagnaClean for the system - and a possible power flush - £650 for both!!

I remember when bleeding the radiators a year or so after moving in and the water came out quite black as well back then - looks like the builder cut back on the chemicals.

Currently considering the Worcester High Flow systems or simular - or a possible boiler/tank

Any thoughts on this?

Cheers

Steve

 

[Agile]

I appreciate that the effect of no heating when its cold is serious for your family.

However, from an engineering point of view dirt in the system is the main factor in perhaps 80% of boiler faults.

Thats not the boiler's fault but fairly and squarely the fault of the installer who did not clean the system.

Its a pity more customers do not chase unqualified installers for the problems they cause.

Od course in many cases its the customers themselves to blame because they intentionally choose unqualified installers because they are cheaper ( initially ).

The reality is that a professional installer who provides a first class job and attends free if any problem arises is likely to be the cheapest solution in the longer term.

Tony

 

[JohnD]

you say you have black water with bits in it?

If you are a DIYer you could fit a Magnaclean (about £100) and give it a chemical clean (£15) and refill with fresh inhibitor (£15). This will do a great deal of good and I guarantee you will be amazed and delighted to see how much black sludge you get out.

If you can do simple plumbing you can do each of these jobs in half a day including teabreaks

Obviously if you have to pay for someone else's time it will cost a lot more

I am a householder not a pro

 

[lawrenso]

Thanks for your replies guys. I will have a stab at fitting a Magnaclean to the system - on the return I believe but will have to wait until after holidays in a week though - but while it is still mild if it takes me much longer.

That can still be used with the new system - in fact will get the system cleaner for it being fitted!!

In fact, just had a thought. I have read up on the power flushing - If I am cutting into the return leg to fit the MagnaClean - could this point be used to attach the powerflush equipment to as well as adding the inhibitor etc. later on??

Cheers

Steve

 

[JohnD]

you fit it on a 22mm vertical return pipe.

powerflushers are usually fitted to the pump valves (the pump is taken off to get at them) though some old pump valves are seized, leaky or broken which is tiresome.

 

[Agile]

The magnaclean makes a very useful dosing vessel.

In fact on a clean system that about their only use!

Tony

 

[gas4you]

You can fit it on a pipe of any orientation

 

[JohnD]

but if the pot is not upright, water will run out when you unscrew the cap

If the pipes are horizontal, and you can move them about, you might be able to get the pot vertical anyway, but I think you will find it easier on a vertical pipe.

 

[Bish Bosh]

the magnaclean fits just as easily on a horizontal pipe at a slight angle (to allow access to the islolation valves)the water spilled is minimal.