Upgrading GCH to sealed system (belated thanks) and Heatbanks

[Vortex]

Well I just did it, having purchased the parts over 2 years ago. (see

for related queries at that time).

The system is now upgraded, flushed, cleaned, and Fernoxed again. Bleeding was easy, and the fact I have an oversized expansion vessel means there seems to be very little cold/hot pressure variation (1.5 Bar cold; 1.8 bar hot)...and apparently zero leakage.

System is now quieter. MUCH easier to bleed (a real pain before), and I have no header tank in the loft.

The next challenge is to rid the loft of the main water tank and that implies a Heatbank.

+++++++++++++

Just started researching this

and I've discovered a huge paradox.

• I was originally contemplating a unit such as the DPS Pandora, with which I would retain the indirect HW circuit from my existing heating system.

• But now I see there is a product called the "GX"which appears to me to offer considerably more flexibility/'efficiency. BUT requires the system to be vented (ie it needs a header tank!!!!!!)

Has anybody any experience of these systems/comments?

David

[Graham]

That link doesn't work David I suppose this is the thread?

[Vortex]

That's the one.

Hast have been a side effect of Budvar.

[David Hansen]

On Fri, 27 Oct 2006 19:50:18 +0100 someone who may be "Vortex" wrote this:-

Or a mains pressure hot water cylinder. If you want to do this then it contains a large volume of hot water under mains pressure. That means bureaucracy in the form of approved installers, several safety devices and an annual service (which is not free).

Thermal stores don't involve a large volume of water under mains pressure. Rather the primary water is under just gravity pressure from a header tank (which can be built into the unit or separate). This avoids the bureaucracy and expense of a mains pressure hot water cylinder. Instead the only water under mains pressure is the secondary water, which passes through a heat exchanger.

One could use a mains pressure thermal store. It would then be subject to the same bureaucracy as a mains pressure hot water cylinder, though there would be no tanks in the loft.

The choice is yours.