Does this system need a bypass valve ?

[Ziggie]

Visited a friend's house after an extension has been built. Part of this was relocating the boiler and controls. The system was converted from a gravity fed hot water and pumped heating to an S Plan system.

They had said that they had a problem with the hot water heating when heating was requested and I had told them that it was probably the two port valve that was faulty.

On seeing the results , the plumber had now installed another two port valve and installed a pipe joining the system skipping the faulty 2 port valve. The plumber didn't decommission the faulty valve.

When looking , I noted that there was also no bypass valve installed after the pump.

Is the installation of a bypass valve needed for an S Plan ?

Thanks in advance

 

[king of pipes]

Yes I would say the system needs a auto bypass if the zone valves close then the heating needs a route and flow through the boiler to dissipate the heat and accomodate then pump overrun. Kop