Zoned central heating problem

[happyflyer]

Red thingy magig knob 1,2,3 Fred hope you haven't paid him in full

 

[fredfat]

I wouldnt have a clue regards what speed the pump is set sorry, I have know technical knowledge and certainly dont intend to be making any adjustments myself. I'm really just looking to pick the brains of people with experience so when i speak to the installer i have a little knowledge. and yes the firm has been paid as they completed the job i have only discoverd the problem in the last few days

 

[happyflyer]

Good luck then Fred, come back if you are not happy with his good time bed stories and his tall tales, the plumbers from :reddevil:

 

[fredfat]

Cheers Happyflyer, could I ask you another laymans question please? as the 2 zone valves are on the return side there are 2 return pipes going back to boiler, does that mean that the flow side feeds All the rads or will that also be split into 2 zones ?

 

[happyflyer]

You will have one main flow and one main return back into the boiler, somewhere down line both pipes will split into two, it is unusual these days for a plumbers to fit valves on the return they are normally fitted to the flow, but it matters not and in fact that is where the water is the coolest, the valves will run cooler and may last longer.

The return is split into two and he has put a valve on each, that's Ok, BTW is the system a sealed system, in other words do you have a filling loop he has shown you how to top up the system.

 

[happyflyer]

Fred,

At this rate you will soon know more than me...:rockon2:

 

[fredfat]

yes its a sealed system with filling loop and he did show me how to use it briefly! So just to clarify the flow will be split some where to feed the 2 zones independently ? cheers

 

[fredfat]

I doubt that . My worry is that I might have more knowledge than the chap i hope is going to make it work haha

 

[plumber0808]

It's a pipework problem, if they have had the same problem before then they are getting it wrong every time.
Why fit the 2 port on the return? Boiler flow on to bypass on to 2 port valves one feeding down stairs one feeding upstairs.
the return should have one circuit for downstairs one circuit for upstairs teed in together close to the boiler.

 

[fredfat]

Hi Plumber0808 and thanks for your reply. Since they haven't fitted the valves in the flow side even if they have at some point split the flow into 2 how does the heated water not run through all the rads ? please excuse my ignorance if this doesn't make sense

 

[doitmyself]

I have checked the motorised valves and I think they are working, based on the return pipe of the zone that is turned off being cold.

Is the return pipe cold on both sides?

It sounds as if there is convection circulation in the zone which is turned off: not surprising with the zone valves on the return!

It might be worth checking that the zone valves are the correct way round (arrow on the side of the brass body, or IN at A, OUT at B).

 

[happyflyer]

 

[happyflyer]

This should help, it may not be exactly like this but this, there is always a chance that gravity circulation can take place even if the valve is shut on one circuit, especially upstairs, there is a way around this the installation of a loaded none return valve, its probably getting a bit too much after all we are in the trade, but the plumber from hell should put it right and stop gabbling about the number of rads on the system

 

[fredfat]

Hi doitmyself, thanks for your reply. the return pipe on the zone that is switched off is cold directly before the valve.The return pipe of the zone that is switched on is hot before valve. After the valve the 2 pipes return into a single pipe going back to the boiler and this pipe is also hot.

The zone valves are both facing in the right direction. many thanks for your help

 

[doitmyself]

there is a way around this the installation of a loaded none return valve,

I know that's the solution for reverse circulation, but would it work for the OP's problem? The valve would have to be fitted to allow circulation when the zone is open; and there could easily be enough pressure from the pump to open the valve.