Alpha HE CB25 Repeated failure with diverter valve

Hi,

I have a 2.5 yr old Alpha BE 25. I have experienced 2 diverter valve failures in this time. Yesterday CH working Ok , no HW . Exact systems as the previous two times. I also noticed a tiny path of water below the boiler . (central below boiler )

I am willing to bet the diverter valve has played up again!


Will know for sure on Wednesday if the current issue is related to the diverter valve

My question is , can anyone comment on similar experience or is aware of 'issues' with the diverter valve on the HE CB25


Cheers,

Kuz

How clean is your system water?

Hi Dave,

In short, I don't know.

At the time when the boiler was installed , a MagnaClean unit was installed as well. The boiler is due for a service about now. I normally clean the Magnaclean at the same time.

Cheers,
K

Path of water below boiler doesn't relate to no hot water on this boiler.

Diverter valve is fine. It utilises a diaphragm which in the life of your boiler should still be in perfect condition.

The flow switch (horseshoe clip on plastic bit middle top of diverter valve) is a complete load of rubbish.

Listen and listen very carefully.

Put it on hot water mode not heating and hot water.

Isolate the little slot on the cold feed to the boiler. Open a hot tap tell all the interfering people in the house to leave it alone.

Open iso under boiler and this is what you should here; a very feint click then you will hear the pump then the fan the fan stops and starts again then clackety clack whoof. All is well.

Repeat again and again, if once only you hear the feint click but not the rest of the sounds it is the flow switch.

If you don't hear the feint click it is the diaphragm.

Some people can't hear the click anyway. Such people are handicapped in diagnosing this fault.

Hello Paul,

Thank you for the information and t/shooting procedure.

All should be revealed tomorrow.

Will post a reply later this week.

Cheers,

K

As suspected it to proved to be the diverter valve.
The diverter valve was leaking.

This is the THIRD diverter valve that has been replaced since installation 3 years ago. All of them had the same fault , LEAKING DIVERTER VALVE.

The engineer that replaced the unit indicated, a very high percentage of repair work he performs on same or similar model ,is due to leaking diverter valves.

There were no issues with the state of the water in the system. Water that was drained was crystal clear.

Surely this an 'ISSUE' with the diverter valve or internal rings/seals within the unit.

I plan to take this up with Alpha with photographic evidence and will pursue until I get a satisfactory response .

HAS ANYONE EXPERIENCED THE SAME AS YOUR INFORMATION WILL SUPPORT MY CAUSE

Thank you,

Cuz

Changed a diverter valve myself Two weeks ago on an Alpha CB25 HE. Lasted a week before it started playing up again with the hot water side. Central heating is fine. Tested the clip on micro switch which seemed ok. Clipped the switch back onto the diverter and it started working in hot water again.

Kuz said:

As suspected it to proved to be the diverter valve.
The diverter valve was leaking.

This is the THIRD diverter valve that has been replaced since installation 3 years ago. All of them had the same fault , LEAKING DIVERTER VALVE.

The engineer that replaced the unit indicated, a very high percentage of repair work he performs on same or similar model ,is due to leaking diverter valves.

There were no issues with the state of the water in the system. Water that was drained was crystal clear.

Surely this an 'ISSUE' with the diverter valve or internal rings/seals within the unit.

I plan to take this up with Alpha with photographic evidence and will pursue until I get a satisfactory response .

HAS ANYONE EXPERIENCED THE SAME AS YOUR INFORMATION WILL SUPPORT MY CAUSE

Thank you,

Cuz

Click to expand...

Kuz, its all very well saying the diverter valve "is leaking"!

What is relevant to a boiler engineer is exactly which part of the diverter valve is leaking.

Can you describe or post a photo?

Do you know what actually causes the DHW to stop working?

This is the first time that I have heard of this fault. Paul may know differently though.

Paul, I am surprised that if this design is still being used as it must be the last boiler design to use a diaphraghm. Everything else now uses the motor driven diverters.

Tony