CH expansion vessel manifold query

[FrancisJK]

Hi,

The CH expansion vessel manifolds that are available, separately and as part of filling kits, do they have a means of isolating the water in the vessel from the rest of the system?

Francis

[fred]

In article , FrancisJK writes

Not the one in the kit I bought . . . . and a bigger waste of space/time I have yet to see. Thought a kit would be a good idea until I received it and realised how little there really was in it. Individual parts would have been significantly cheaper. I ended up using separate fittings to get the components in places that suited me (without the manifold).

[FrancisJK]

So your manifold was basically just a metal mounting with openings for various parts? No means of closing off any openings when in place in the system?

Francis

[fred]

In article , FrancisJK writes

Exactly so, nothing other than a 'convenient' multiple connection point. In its place I used BSP to compression fittings to make my connections, the filling loop (with valves) already had compression fittings. The vessel (18litre) was mounted by a wall bracket which gripped the seam of expansion vessel.

[FrancisJK]

Thanks for that.

It occured to me that I have no way of checking the "air" pressure in the expansion vessel once the system is full.

As I'm running with cleanser, when I drain that I'm goona re-jig so that I can isolate the expansion vessel so that I don't have to drain the system to check EV.

Whilst Googling, I came across a 'Reflex' Schnellkupplungen for a Membrandruckausdehnungsgefäß, which does the following:

• The quick-couplers CSU R 3/4" onto the container connection directly to the diaphragm pressure expansion vessel are screwed. As seal materials the commercial means are e.g. hemp or teflon band to be used.

When opening the screw connection and when pulling apart the screw connection parts the water route between diaphragm pressure expansion vessel and heating system is closed automatically.

*

If I can't get a Schnellkupplungen for a Membrandruckausdehnungsgefäß, I'll have to make my own.

Francis.

[John]

No there should be NO means of isolating the expansion vessel or the safety valve from the system or someone somewhere will do so and cause a burst or an explosion.

[fred]

In article , FrancisJK writes

Welcome

I don't see that as a problem, there are a few philosophies regarding setting the vessel pressure. Yes, I think the best is meant to be to set it to the recommended pressure while the system is depressurised but I'm not about to do a drain down just for that. Another I heard here within the last few days was to balance the vessel pressure to the system pressure, which I think results in a little less capacity to cope with expansion, but the saving on draining down makes it a winner for me. (Don't) Pay your money, take your choice.

After adjustment, remember that unless your system pressure is rising from a 1-1.5bar cold setting to significantly over 2bar when at full heat then your expansion vessel is doing what it's meant to.

wouldn't bother . . .

HTH

[FrancisJK]

Indeed.

My search for Schnellkupplungen for a Membrandruckausdehnungsgefäß has shown me that what is involved is an item that enables the expansion vessel to be isolated for servicing without draining the whole system. Some contain a locking cap that is sealed in a similar manner to electricity and gas meters.

It seems that these conform to regulations in some parts of Europe.

Francis