Ideal isar he30 still leaking

14 Apr 2011
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United Kingdom
So been trying to sort this for a while , 1st started leaking few weeks ago from dhw outlet on heat exchanger plate, so bought the hydrobloc seal kit and replaced them... Leak then seemed to be slightly worse and spraying a bit instead of just thought it was a pin hole in plate itself just round back out of sight so got another plate and new seals again... refitted and exact same leak...replaced the 15mm O-RING on the dhw outlet stub on the manifold just in case that's where it was spraying from ,but no same leak... finally got a tiny mirror on a stick in right position to see and can see it seeping out of the dhw outlet join on the manifold/plate seal. How would this be ,I've changed all seals twice!! Some of the seals did look slightly wedge shaped but they're fine in the other 3 I've replaced. I've ordered some ideal branded ones to try but anyone came across this issue when replacing the o-rings on heat exchange plate??
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I changed seals again for ideal branded ones, but exact same dripping from the manifold/heat exchanger joint...if I over tighten then the drip turns to a spray and a drip. Is it possible the manifold has warped or distorted over time and just won't make a solid seal anymore?? Worth replacing the whole manifold assembly as they seem to be cheap enough on eBay???
sounds like you have a crack in the manifold
Yes this is what I thought but couldn't see one and really looks like it's coming directly from that seal between manifold and plate...anyway replacing the whole diverter assembly isn't too bad a job is it?
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it is common for tiny cracks and tiny holes in the plastic casting on boilers to happen and you cant always see them but as you have found as you tighten them they get worse, you have managed to change the plate a few times without any trouble so cant see why you couldnt change the hydro block
Cheers yeah think I'll manage, there's good deals on whole assembly Inc head etc so probably easier to do whole thing, would I need to remove the 2 stub pipes (hw out and ch flow) or could they be left in situ and just remove the 3 pins and guide the whole thing out?
it tells you in the installation and servicing manual exactly how to do it, you would be well advised to get some silicon grease for the seals though
Yeah got silicone grease and all new o-rings ,can't seem to find it in the manual mind, just the actuator and valve mechanism removal can't see anything on removing the manifold hmm
Sorted no more leaks, manifold was split , not too bad a job to replace thanks for your help!

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