Alpha combi boiler - power flush or replace?

14 Nov 2014
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United Kingdom
Help me please!

Moved into this house last year, it hasn't been looked after at all. Gas combi boiler (Alpha InTec 25XE) has always just about worked. It's only ever given us constantly hot water if the tap or shower is turned on to a very low pressure. Even half pressure and it'll run hot for a minute or so, then go cold. Shows fault code E73. So showers are often a hot/cold horror, bath is impossible to fill, even sink takes ages to fill.

I asked three plumbers about this when we first moved in. Two said "It's a useless boiler, I'm not touching it", the other ignored my calls. Recently I'd had enough of it and found a heating guy who'd look at it. He replaced the heat exchanger - slight improvement but it didn't last. He did chemical flush - but he left the stuff in for ages, a lot longer than the max 2 weeks he said (his van broke so he disappeared). Result was a slight improvement but it wasn't fixed and has since got worse and worse. He showed me the crud that was in the system... chunks of black gunk, lots of it. He's saying do I want to keep spending ££ on this useless boiler?

Spoke to Alpha Tec helpline this morning. They say remove each radiator, power flush, fit magnetic cartridge. A whole day's work and not cheap. Consider new boiler...

The boiler is 7 years old. I am as skint as can be.

Is a power flush worth the cash??
New boiler - new radiators too? Would I still need the power flush to get crud out pipes anyway?
Is it worth trying a second chemical flush? Can me and my capable handyman other half do this ourselves?
Could we take rads off and flush ourselves? Alpha Tec guy has said remove, take to garden, run water through until clean.
Should I just give up and resign myself to the fact that we won't have a holiday for the next 2 years cos I've got to borrow ££££ for a new boiler and rads?

Any help and advice very gratefully received!
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Absolutely nothing wrong with that boiler if you use someone that knows how to service them correctly, the cowboys you have been employing are just part slingers
interesting post, i thought my wife may have written it! We moved into a new, to us, house late last year. the heating and HW is provided by a Alpha intec 25XE and surprise surprise we don't get any hot water. the engineer who attended as part of our service contract stated it needed a new heat exchanger, duly fitted to no avail. I have done some fiddling with settings to see if we can get water for a shower whilst we wait the replacement of the the diverter. to get HW we have to turn the Ch water temp up to max and room thermostat to max also, effectively meaning the boiler is on constantly. This provides HW to enable a very hot shower to be enjoyed. pretty sure this will be cured with a new diverter (hopefully).
i had to post as couldn't believe we had such a similar situation.
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@pussbag Thanks for this, sounds very similar! I've also tried various changing of settings to no avail but thought I'd try your remedy anyway. Sadly it didn't work for me :( Good luck getting yours fixed.
@ianmcd I really hope this is fixable. But I've had several different suggestions as to how to fix it (and almost everyone says rip it out and replace it). Any clues on what it actually needs in terms of getting it sorted?

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