Alpha 240p DHW Diverter Valve Gland Nut leaks

8 Mar 2016
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United Kingdom
Hi I have 2 problems, I've replaced the gland nut on the front of the DHW diverter valve, some 8 months ago, but it is now leaking again from the pin directly behind the micro switch, mainly when no heating has been on. In addition as the hot water takes a while to heat up, I have to put the heating on for 20-30 mins to get a decent temperature for morning showers etc, I'm not sure if it's it probably better to change the whole diverter assembly to fix both issues? or maybe buy the diverter / diaphragm parts kit and have a go at stripping it down? Any help is much appreciated, I don't really want to replace the boiler, due to the large expense. Thanks
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I have never replaced the whole valve, and always fit the parts required from the kits that are readily available. It does sound like your diverter is passing to the heating when on hot water only. With the heating turned off and cooled down, run the hot water. If the left hand side pipe underneath gets hot that will point to a siezed/sticking diverter. All the parts are in the kits. Don't get any water near the main PCB!
It's more expensive to replace the whole valve, but obviously easier if you chose to go that way.
Hi Pete, I've let the system cool and run the hot tap and the left hand pipe (heating flow pipe) gets hot, I was thinking of using the diverter diaphragm kit but which diaphragm do think I would need to replace the front (DHW) or the top (Primary flow) or both? thx
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replace both and strip out the big nut and relace that and the spindle that comes through it
Thanks Pete & Gas112, what's the preferred way, do you think it can be done / replace the bits in situ (less to go wrong or leak :unsure:) or best remove the whole thing out of the CH Boiler, I don't mind taking it all out just a bit awkward getting full access?
It can easily be done without removing the valve. Remove the large front housing first and refurbish that. Move onto the diverter section and refurb that. Cold supply must be off and the ch side must be drained so as to empty the boiler. It used to take me 45 mins to complete. Allow yourself more time and photograph each stage of the work so as to remember the order of the parts.
Update, after watching a youtube video of someone replacing the parts, I thought better of it and order the whole unit, and replaced that, after a couple of leaks from hard to reach places I cracked it, and now touch wood all's working fine, with near instant "hot water at the touch of a tap", many thanks Pete and Gas112, you've been a big help :)

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