Head scratching???!???

[AP Electrical]

Just wired a c plan heating system boiler with programmer and rf room stat, took what felt like ages to get going, anyway now when energised all works good apart from roomstat heats cylinder and vice versus ???,followed wiring plans and checked again but cant seem to see prob with wiring?, this is a refit so all pipework old any ideas anyone?

 

[AP Electrical]

Forgot to mention the two port valve is on the ch not hw I thought it was meant to be other way round, be great if so cause then its plumbers problem!!!!!!!!!!!!

 

[Chr!s]

Have you fitted a new port valve, if so has a changeover auxiliary switch?

Have you wired up the port valve correctly?

 

[AP Electrical]

Same port valve Chr!s, as for wiring as per manufacturers diagram, and I cant see wiring making much of a difference as both go through the same cables into port valve. I could swap cables at timer but on the lcd it would say ch on hw and vice versa. whereas on old timmer it didnt have lcd display....just switches.

 

[Chr!s]

Well, the room stat demand is wired to the auxilary switch(white) and the pump Line, this fires up the pump and boiler via orange.
The HW stat is wired to the brown, this energizes the motor on the port valve which in turn activates the switch and powers the boiler via the orange.

Just to add, the pump Line is only connected to the demand of the room stat.

When a cal for hot water is made power is made to the orange, this brings on the boiler only(no pump). I assume this is a gravity hot water system?

You also need to consider the position of the port valve and also the issue regarding gravity fed circulation around the primary circuit when their is a demand for hot water only.

Regards Chris

 

[AP Electrical]

Well, the room stat is wired to the auxilary switch(white) this fires up pump and boiler via white. The HW stat is wired to the brown, this energizes the motor on the port valve which in turn activates the switch and powers the boiler via the orange.

No white just brown,blue, orange and grey which is perm live i think.

 

[sxsparky]

Hope this plan helps

 

[Chr!s]

Just added a bit more above if that makes it any clearer.

 

[Chr!s]

No white just brown,blue, orange and grey which is perm live i think.

That's an L plan then

 

[sxsparky]

are your sure it not a 3 port y plan mid position

 

[sxsparky]

Has anyone seen these kits, hope plumbers dont start using them it will put us out of work, plug and play things really simple

 

[sxsparky]

i hate all them wiring centres, give me a strip of terminal blocks in an surface box with blank plate any day

 

[AP Electrical]

That's an L plan then

L plan :s this is just getting silly, sxsparky deffo only one two port with pump wired directly onto boiler

 

[sxsparky]

sounds like you must have a 3 port that does heating and hot water. as there is nothing to control the hot water, how can the cylinder stat control the water if its not switching anything

 

[Chr!s]

The demand of the Room stat connects to the brown on the valve this powers the pump via the orange, also in the same terminal connect the satisfied of the cylinder stat this powers up the boiler.

The hot water is powered through the programmer directly to the demand on the cylinder stat which powers the boiler only through the "C" common. Again i assume this is gravity fed.