Vaillant VUW242E -H/Water prob-Tap must be full on to get HW

[TechD]

Hi, I have a 6 y/old Vaillant TURBOmax VUW 242E. Problem seems to have developed gradually, where the domestic hotwater taps need to be virually fully on to trigger the boiler into action. Once triggered there is no issue with the volume of water or the temperature. The wife complains each time she uses the kitchen tap, it has to be on so fast it splashes everywhere.......

I have done a little research and wonder if it is just the diapragm. The service manual gives a part no 01 0357 for just the diaphragm, but this seems to be a discontinued part.

If my problem is just the diapragm, can anyone advise me if the replacement is Vaillant 01-0365 Diaphragm DHW 010365 Replaces 01-0357 010357 - as an EXACT replacement fit - and is it pretty simple to fit as the service manual instructions dont seem too difficult.
Many thanks for anyones help.

 

[kevplumb]

so have i
diff i know what i do for a living
yes its a doddle if you know what you are doing


etc etc etc

sarcasm must stop drinking kero

get the bleeding kit if you cant fig that out well i rest my case

 

[TechD]

thanks for the "tip". having decided to take the panels off to have a closer look, it appears that there is a substance like "oil" accumulating around the microswitch (and enough to drop onto the bottom boiler panel - dirty yellowish in colour)Is there a sealed resevoir of lubricant within the DHW diverter valve assembly? If so is this job more than just a diaphragm replacement?

Hope you can give a constructive pointer.

 

[kevplumb]

t5he only thing mine has needee in a long time is a service kit
replace the gland in the diverter when you do the diaphram and the little plastic lever which always falls to bits

all of which come in the kit

 

[TechD]

Hi kevplumb, cheers for the pointer - can you comment over the "lubricant" issue - I think its coming via the microswitch activator level area - is it actually lubricant or just a mixture of CH inhibitor / water evaporating to a thick consistancy?
For the Kit - can you suggest the best place for me to obtain and cost?

Once again thankyou.

 

[Lurker]

The goo is from a leak, possibly from the automatic air vent which is above.
If your diverter valve has a plastic bottom, change the whole valve. Otherwise the kit is OK if you use ALL the bits.

Expect the job to take you 3-4 hours first time. You will need silicone grease.

While you're that far in, take off the secondary heat exchanger and leave it soaking in warm kettle descaler (both chambers). Extra 10 minutes of fitting only. Will improve HW.

 

[TechD]

Thanks for the comment - where would you suggest I obtain the whole valve without being in "the trade" at reasonable cost? (if not allowed to post in forum please email)For a self install/replace are there any particular fiddly bits to know about before starting. The service manual doesnt indicate anything which bothers me - which isnt always the full story.........
If I decide to pass the whole job over to a professional (in Berkshire) what "should" be the typical cost?
Cheers.

 

[Lurker]

Make your email address visible in your Profile.

 

[weargas]

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item=7504316071&ssPageName=STRK:MEWA:IT

 

[TechD]

Ooops - sorry about that - email done now. Whilst posting this does the service kit come with all new sealing washers etc which are needed if the wholevalve is pulled out?

 

[bogstandard]

Local branch of "The Plumb Centre" will fix you up with parts at competative rates usually cheaper than buying online or otherwise. Other than rubbers these boilers Never wear out. Most everything on them can be Cleaned up and rejuvinated!

 

[namsag]

Part is normally aound £100 and takes no more than 45 mins for a pro to fit ,even first time should not take more than an hour . Anyone taking 3/4 hours to do this either doesn`t know what they are doing or taking the pish

 

[EasyFix]

This common problem is usually caused by limescale gumming up the diverter valve. The reduced movement of the diaphragm causes incomplete diversion of heating from CH to HW and/or failure to operate the HW demand microswitch. This results in luke warm water or none at all. A quick fix is to first turn off the boiler and water inlet valve and then remove the flow regulator from the bottom of the diverter valve. Then carefully use a smooth ended 5mm dia. rod to push the diaphragm upwards as far as it will go several times to break down the limescale restriction. Replace the flow regulator, turn on the water inlet valve and boiler and enjoy piping hot water until it gums up again.