Fully pumped CH & HW, no motorised valves!

[DP]

If the vent is clear, good, expansion water will go up the vent and discharges into the header cistern. Water that is short due to discharge will result in air being circulated around the system worst case scenario

 

[DP]

Unfortunately where the feed pipe meets the system is under the kitchen floor which is tiled, so a big job to get done.

Is the boiler underfloor too? If not and feed pipe and vent pipe are accessible, replumb to the boiler

 

[ericmark]

As to how to control the DHW not so easy, however likely you don't want it off when using CH anyway, as to how to warm up rooms faster, then using simple programmable TRV heads will do that, it is how I have done my central heating, you need some way so if all valves off water can by-pass, normal is a by-pass valve, but your DHW hot coil will do that job, the non blue tooth programmable head eQ-3 costs around £10 on internet each, and what I have done is set times so important rooms heat first, so in the morning the bedroom TRV turns on, then 15 minutes latter the kitchen turns on, and then 15 minutes latter the dinning room, and in the evening I have kitchen, dinning then living room and finally bedrooms.

Clearly you don't want the heating running 24/7 so in my case I use the hall as master control, the TRV head matches the wall thermostat so heating it turned up/down as required, I have fitted motorised valves as same heating does flat and house, but if it were not for flat, the motorised valve would not really be required, I can't turn DHW off, or control the temperature of DHW, in summer I just run for 1/2 hour 5 days a week which is about right to maintain DHW temperature.

Yes not ideal, but it would require floor boards lifting and new wires to get thermostatic control on the DHW.

 

[Rhys_91]

Just a very quick update. I am beyond delighted.
Plumber came a few weeks ago and fitted a valve, he only charged me £20 in total.

Boiler got fixed today.

For the first time ever, I have burning hot radiators, all of them. The radiator in the back bedroom never used to even really get warm before, its now very hot.

Happy with the £20 temporary fix until I can get the whole system redone.