Ideal Mini C24 DHW alternates hot/cold

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Boiler Make: Ideal
Model: Mini C24
Year Make: 2004
Year of Install: Approx mid 2005 at ground floor.
Services: DHW and CH to lounge, 2 bed, 2 bath both in basement.

Hi All,
The issue has become evident since May/June this year. When having a shower in either bathroom, the DHW temp gradually builds to hot then after 30 seconds changes to warm/cold for another 30 seconds then back again. This alternates consistently throughout.

The changes are not as evident via the basin taps but I believe does occur from the tests done.

The only green flashing light on the left suggests 1 second ON, 1 second OFF which I understand is Normal ON.

One thing to note is that we haven't had CH on at all during this period but being curious, I ran the CH this morning to test the shower and the temperature changes no longer seemed to occur. Don't know the relevance or if it was just a once off.

My reading of posts on this site seemed to suggest this was a problem with the DHW Heat Exchanger and/or Temp Probe. I was heading in that direction but then a recent e-mailed response from Ideal suggested the diverter valve could be passing. I’m not sure of the last possibility as I had the Diverter replaced last December along with the DHW Temp Probe and Safety Valve due to a separate issue. Possibility of blockage?

I was hoping some of you in the know about this Ideal model may be experienced to offer any advice to the symptoms experienced to help narrow down the cause.

Thanks for your time.
Daniel

 

[Agile]

That is normally a blocked plate HE as you suggest.

Its never necessary to replace the diverter valve!

You have been conned. Possibly by someone who does not know how th repair them or just wants to up the price ( = profit ) to him.

Telling you that gets me no end of stick from other people whose sole intention is to bump up the cost of a repair to the maximum that you will pay!

Tony

 

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Thanks for the feedback Tony, seems I was on the right path with this. I'm considering the cleaning out approach as has been suggested in the past. My only concern then would relate to the O-Rings and if they need replacing (worst case).

Are you aware if this is the part that is actually sold seperatly - KI1043144?

Indeed, the last guy I had here led me down an expensive route and was in my opinion very unprofessional. He did get it working eventually. I'll never use his service again.

Regards,
Daniel

 

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Hi all, have attempted the DHW Heat Exchanger replacement and need some advice.

1. Having closed the isolating cocks horizontal to the CH flow pipe furthest left and CH return pipe furthest right (believe that's the CH circuit?), I have also closed the Domestic cold water inlet (DHW supply?) pipe.

2. Have tried to rotate the main circuit white drainage cock (only goes 360 degrees) with no system pressure release occurring.

3. Believe I've successfully released the DHW circuit pressure on all taps as nothing else comes out.

4. Removed the diverter valve actuator.

5. Now when I begin unscrewing the allen key screws, water begins to come out between the HE and the brass groups. I let this run briefly but it doesn't stop and so here I am..

I understand there maybe some water build up but it seems there is still a lot of pressure in the system as I release the screws.

Where have I gone wrong?

regards,
Daniel

 

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Hi, I think I've hit a problem with the drainage cock in that it just rotates without release.

As such it may need replacing and the pressure release may need to occur via the CH so I've been told. This is in addition to the DHW Heat Exchanger yet to be cleaned.

I'd appreciate it if somebody would be willing to help me and could get in touch via PM to further discuss the issues. I'm in the Mile End area of London if it's of convenience.

Thanks,
Daniel

 

[Agile]

The boiler drain cock often needs turning several turns before it opens.

If you wanted me to come and deal with your boiler problems you would need to email or phone me directly, contact details in my forum profile.

I like the Vietnamese restaurants in Kingsland Road not too far from Mile End! I also used to like Brick Land market until Monica Ali spoilt it. I must have tried nearly a half of the restaurants in Brick Land and yet have still not found any good one! Thats pretty dire. Somebody said there is a good one behind the hospital with the chopper pad on the roof though.

Tony Glazier

 

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Thanks, the drainage cock has been turned many many times, still no release.

I have sent you an e-mail request with my details also included.

Btw, the place you have in mind is Tayyabs. Another is Lahore Kebab House, both great options.

Daniel