"John Rumm" wrote in message
news:1oSdncBDHeMGs2nanZ2dnUVZ8vydnZ2d@plusnet...
Doctor Drivel wrote:

Doctor Drivel wrote:

The problem with sealed system is that the filling loops are left
permanently connected by installers - not supposed to be. Some are a

That is not a problem with sealed systems. It might be a problem with
some installers.

It is a big prblems with sealed system.

The system works perfectly with the filling loop connected.

If the check valve fails it spurts contaminated water into the drinking
water mains.

Its only if some muppet starts filling it to mask some other problem that
it is an issue.

Which is common.

That's not a problem with sealed systems.

It is, if the system were not sealed and configured as they are it would not
happen.

In the same way that someone setting the pump speed too high on a vented
system and causing pump over is not an inherent problem with the vented
system, but a problem with its installation.

A rare problem.