ch wiring

[bigfeet84]

hi i have a danfoss fp715si programmer which controles hw or ch
when i have ch on the motorised valve opens but boiler doesnt fire unless you also hit the hw on.

any1 know much about the wiring for these

also posted in plumbing section cause i wasnt sure where to put this

 

[EFLImpudence]

The boiler and pump are actually switched on by the valve when it fully opens.

Everything wears out so you will have to test for voltage at the relevant terminal.

 

[bigfeet84]

Untitled

• bigfeet84
• 24 Oct 2011
• 2

basic diagram of the wiring

that is basic diagram of how my system is wiried

 

[EFLImpudence]

Or -

I take it the two squares top-left of your diagram are the valves.
If so what I said before still stands.

Edit - top left

 

[bigfeet84]

the two squares are 3 pin plugs from boiller and pump. the socket is not live it is wired to the programmer and becomes live when programmer is switched on.

when i switch hw on the valve is closed, the boiler fires and it heats my water but not my raditors. perfect however when i switch CH on the valve opens but boiler dosent fire, therefore i have to switch both on to get my heat.

its hard to explan, everthing is new also

 

[EFLImpudence]

Then, as said, it would appear that the CH valve is not making contact to switch on the boiler and the pump.

You will have to examine the valve to determine that it is opening fully and then making contact.

Replacement motors are obtainable but if you don't know what to do you will need an electrician.

 

[EFLImpudence]

everthing is new also

Has it ever worked or have you just done it and it doesn't work?

 

[holmslaw]

..

 

[bigfeet84]

i think i understand but like i said the valve is only new and i cant understand how it can send power to the boiler would i not need to link 3 on 6 on my diagram to make that switch work or somthing like that.

the man who fitted it told me that i needed to put both on for ch. but for hw i only have to switch hw on. i rang danfoss today and they said it was probley the wiring was wrong and that they should both work independant.

i will check the valve

 

[EFLImpudence]

The cables from each of the devices - programmer, valve(s), boiler, supply etc. are supposed to go to a central point to be connected.

I know your diagram is not exactly technical but, according to you,

when calling for DHW the pump is energised and

when calling for CH the boiler, but not the pump, is energised.

 

[bigfeet84]

when calling for CH the boiler, but not the pump, is energised.

wrong neither bolier or pump is energised but the valve opens aloud water to circulate

when calling for DHW the pump is energised and

dhw everthing works as it should valve dosent open stoping water goin to the raditors. water only cirulates around hot water tank.

sorry about the spelling. http://danfoss-randall.co.uk/PCMPDF/38161v01s7-06.pdf this is the installation guide with wire diagrams

 

[EFLImpudence]

when calling for CH the boiler, but not the pump, is energised.

wrong neither bolier or pump is energised but the valve opens aloud water to circulate

when calling for DHW the pump is energised and

dhw everthing works as it should valve dosent open stoping water goin to the raditors. water only cirulates around hot water tank.

I believe you. I was merely pointing out the flaws in your diagram.


We don't seem to be getting very far.
I have said what I would think the problem to be if I was at a customer's house.

However, you say the system is new (although faulty new items are not unknown) therefore I may think that it is wrongly wired.

You say the man who fitted it told you that is how it should work and that is how it does work so either get him or someone else to alter it so that it works as YOU want.

 

[LearningSpark]

From your diagram the socket which has the burner and pump plugged into only becomes live when the heating is on via output from terminal 6. When the hw is on the only thing getter a supply is your other pump at the bottom of the picture via terminal 5. Where is your 2/3 way valve and how is that connected into your system. You may need a hw off (satisfied) output from your controller to the 3 way valve to allow htg to run without hw.

 

[bigfeet84]

my mistake that pump at the bottom of my diagram is not a pump its a motorised valve

 

[SimonH2]

It's not wired right, or ...

As already stated, the HW output on the controller is opening the valve, the CH output is running the boiler. It sounds like your plumbing does not allow heating without hot water - hence only the one valve. As already asked, is this a 2 port valve (ie just 2 pipes) or 3 port (3 pipes connected to it) ?

I see two ways around the issue.
1) On your valve, there will be orange and grey (IIRC) wires which connect to a microswitch inside. These could be connected between terminals 2 & 6 on the controller so that when the CH is on, the valve opens, and the microswitch will turn on the boiler. This has the flaw that you can program the timer so that it demands only heating - but you'll still be heating the water. For this reason, I'd suggest a different change ...

2) Set the programmer to "10" mode, or gravity mode, or whatever it calls it. This limits you so that you cannot program heating on with water off. So whenever the heating is on (valve opened by power from terminal 5), the boiler will also run because the hot water output (terminal 6) is also on.