Help. Boiler leaking (heater exchanger connection)

chrischristopherson1313 · Mar 5, 2025

Does anyone know why water is leaking on that connection. Vaillant ecomax 824/2 E, It's heater exchanging connection, the one which is secured by the clamp (there is no rubber seal? -how does this even works ??)

plugsandsparks · Mar 5, 2025

What is the boiler make and model, if you can post the GC No, that would help

chrischristopherson1313 · Mar 5, 2025

plugsandsparks said:
What is the boiler make and model, if you can post the GC No, that would help

Vaillant ecomax 824/2 E

Avo Mk8 · Mar 6, 2025

Seems to be a common problem, as you'll see if you search on Plumbers Forum.
Used to be a black rubber pipe, now a copper pipe.
There are (supposed to be) o-rings on the HEX spigots, apart from the one with a packing ring connection

The suggestions below relate to using a jubilee clip on the old rubber hose to improve the seal. Maybe a replacement o-ring would do it, given you have the copper pipe?

Vaillant Eco max 824 leak from flexible pipe on main HE - UK Plumbers Forums

Hi, I have been called to the above boiler where a customer has been complaining of a leak coming from the boiler. I noticed the pressure on the boiler was at zero so as I was filling it with the casing off I found a leak coming off the top of the flexible black pipe on the primary flow. I...

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