NZ vented hwc

I couldn't get the link to work initially.

I can only assume that the pressure reducing valve is tuned to match the height of the vent pipe, such that when the system is hot the vent pipe is near enough full. The relief valve system seems to indicate this too.

On the basis that I live in a single storey house with poor HW pressure such a system is interesting, though I think I would retain the cold water tank for toilet flushing, etc. ___________________

If you are retaining the tank then there is no point in using this system, which the prime aim is eliminating the loft tank in the vented version.

BTW, many people in the south of England when renovating, would go to France and pick up a load of building materials as it was cheaper. Many would unknowlingly fit in the French unvented cylinders, which pass a small amount of water into the drains because they had no pressure vessel - like a Megaflow when the air cushion dissolves, and the householder does nothing to reinstate the air cushion, which is quite common.

It prefixes quoted text fine (as in this post).

Mathew

He's a troll, with much previous form. If it annoys you, he'll do it all the more. It gives him some gratification. Killfile him.

There is nothing wrong with the vented version as long as the OV is freeze proof.

He's a troll, with much previous form.

I never.

It wasn't as the 22mm leg from the 28mm drop pipe was long enough.

I never, as there was a check valve in both legs.

It is open to the air, as the name OPEN VENT suggests.

It would have to be trace heated or completey within the insulated envelope of the building.

Ten out ten there. Very good.

Or up a disused chimney stack (inside the heat envelope) or us insulated pipework.

Addition: An anti-vacuum valve was fitted on the cylinder in case. The cylinder could expand up the open vent, which was the also the cold feed which was via a vented tank. The cylinder had a pressure relief valve and an anti-vacuum valve and a high temp limit stat in case the normal stat failed. It wasn't pressurised.

Google Groups strips off the ">" before sending.

How would you get inside a disused chimney stack to make pipe joints, fix insulation and fix pipe supports?

Very few disused domestic chimney stacks go straight up, most step across with corbelling to connect to a chimney stack in the centre of the party or gable wall.

I don't know what a 'sock puppet' is. I do know that I've been subscribing longer to this forum than either you or Drivel, and that my comment about being unnecessarily pedantic has just been confirmed by the string of abusive threads between you and Drivel that followed on from my comment.

Run plastic pipe up and mabe secure at top. Cover with rigid foam insulation.

Very well done you.

Do you know anything about water heaters, vented or unvented?

Have you ever heard of plastic pipe?

He knows more than you.

Yes, super stuff.

One thing you can't use it for though, is boiling water and steam. This is why the discharge pipes from boiler PRVs and unvented water heaters have to be metal. This application is an open vent pipe, for which you propose using plastic pipe in an inaccessible void.

Oh dear.