Central heating controlled by raspberry pi and relay switch

[poumpouris]

Hey guys, im not a professional electrician, I just have a basic knowledge of some stuff.
In order for me to be able to explain what i want to do, I will first explain what is in place at the moment.
We have a 3 zone programmer which we never use as a programmer, we just turn on each zone manually when we want.
So i thought, since this is all done manually i could put together a raspberry pi connected to a 4 channel relay board and control the whole thing from my smartphone. I found all the software and hardware i need and i can make the relays open and close but I am not sure what to connect where on the relay in order to get the central heating to work as it works now.
Here is a picture of what the wires look like behind the programmer at the moment. The letters for the wires from left to right are: E,N,L,1,3,5



Here is a picture of the relay i have although the picture is of a 2 channel relay instead of 4 channel.


From my basic understanding, what i thought i should do is connect N and L together and then connect them to the COM terminal of the relays. Then connect 1,3,5 to the NO of each relay but I'm not really sure and I don't want to burn anything.

Can you please advise me on what to connect where?
Thank you in advance.

 

[buzzlightyear]

have not heard of a system hive or nest ?

 

[MJPD29]

What do you mean connect L and N together?

 

[The Ghost]

An interesting project. Look at your controller wiring diagram that should yield what is doing what. Is your boiler old or new, would it void the warranty if you control it with a non approved system? Talk with the manufacturer of your boiler and controller, tech department and discuss it with them.

 

[Leesparkykent]

Do you know the make of programmer? Is that existing programmer just doing one heating zone and hot water?

 

[poumpouris]

@buzzlightyear I have heard of them but i don't really need any of that, i just saw something that is done manually and found a project for my self

@Matthewd29 I meant connecting the black and the first red wire, if what im saying is idiotic just say so, thats why i asked before doing anything.

@Vortigern This is the wiring diagram from the programmer manual

The boiler is about 20 years old so i dont think there is still warranty on that.

@Leesparkykent The programmer is a Channelplus h37xl and it controls 2 heating zones and hot water at the moment

 

[MJPD29]

No don't connect them together, connect the live to the common terminals and use the switch lives from the time clock on the 2 normally open terminals (presume normally open for what you need) The neutral doesn't seem to be needed on the relay shown

 

[Leesparkykent]

Link live across the commons and switch lives to normally open.

 

[poumpouris]

Ok, but if neutral is not needed, why is it there? To power the programmer?

 

[Leesparkykent]

Ok, but if neutral is not needed, why is it there? To power the programmer?

yes the existing programmer requires a neutral, that's why it is there.

 

[MJPD29]

Yep that is indeed why. But the relay shown doesn't need it.

 

[poumpouris]

Great, thanks for the help guys! I will give it a try in a few days and post back.

 

[AJshep]

First off you only have 2 relays however you have a 3 Channel Programmer !

If you want to control all of the channels individually your need another relay.

Another thing to note If you have a Y plan then your also need to use the nc contact on the relay you use for hot water for hot water off.

Other than that Rpi works well I have a similar setup with mine a switching my garden lights.

***edit sorry just read its for CH only and you have 4 relays ***

 

[poumpouris]

@AJshep I dont know if i described it in a wrong way,i intent to use the 2 zones and the hot water. I will search a bit to find out how exactly Y plan works and see if it is what i have

 

[telectrix]

dunno anything about this raspberry pie. i like this though:

 

[telectrix]

and of course same band was first ever play on radio 1, before it went into shyte "music". september 1967.

 

[danzor]

I need to design a system like this, but for panel heaters.

I thought raspberry pi was for TV’s, come on abut lately?

 

[AJshep]

You would probably make alot of Money. I noticed a thing called "Wise Box" the other day in a local wholesalers looks like a Rpi with a relay board but 4x the price with just basic wifi control.

 

[davesparks]

Another thing to note If you have a Y plan then your also need to use the nc contact on the relay you use for hot water for hot water off.

It’s clear from the picture in the OP that it’s not a Y plan system but a three zone system.

 

[AJshep]

It’s clear from the picture in the OP that it’s not a Y plan system but a three zone system.

Yes I know the OP was pretty clear I didn't read it properly.

 

[gnuuser]

your raspberry pi or arduino would be better suited if replacing the thermostat but would require writing a complex control program to handle it. ( either in c++, java, python, or ruby language)
as your zones would be relays activated by your processor (these relays controlling the thermostat voltage)
if they were connected parallel they would often override each other
your heat source (boiler, etc.) would need to function on multiple heat calls, zone control on the other hand can be handled many ways.
for instance my own heating system is a hybrid forced air furnace.
instead of a single blower it has 4, each zone has its own thermostat and blower(all controlled by a micro plc).
programs written to the effect that i can isolate any zone from running with either the zone isolation switches or uploading the proper program.
steam radiators zone controlling using a solenoid type valve at the radiator or its supply pipe can be controlled by plc, relay operated by arduino or raspberry pi easily.
these can be selectively operated remotely with your cell phone