Drayton Wiser WT724R Hub

[Moon_Fire]

Hello,
I failed to install the Hub and managed to burn a component on the PCB in the process.
So in order to fix my mistake I managed to ask a friend of mine that knows his way around boards and how to replace faulty components.
Is there anyone who can take a detailed (or more picture) with the back of board the one with resitors and such? Or the Board diagram would be more helpful as the burnt component can't be recovered... I know, don't even start.
So please, I beg you to help me.

 

[mcprinter]

Is this what you need?

Fauty Wiser HubR

My Wiser HubR developed a fault of constantly resetting /rebooing every 10 minutes. Been onto tech support for some weeks without any progress apart from normal basic questions. I sent videos, they apparently logged into it and couldnt see any problems. After lots of fault finding I found that...

www.diynot.com

 

[Moon_Fire]

Is this what you need?

Fauty Wiser HubR

My Wiser HubR developed a fault of constantly resetting /rebooing every 10 minutes. Been onto tech support for some weeks without any progress apart from normal basic questions. I sent videos, they apparently logged into it and couldnt see any problems. After lots of fault finding I found that...

www.diynot.com

Yeah I think that's it. I forwarded it to my friend. Pending reply. Thank you for the swift reply!

 

[Moon_Fire]

Well it turns out that the picture isn't detailed enough for the resistance to be identified. I wonder if i can find the PCBs wiring diagram or even better still if someone (who I will be forever in debt) can measure the 2 resistances that are in the center.

 

[PhilHornby]

Most of those components have no markings. My Brymen BM235 says they have no resistance either! (well maybe 0.001Ω) - so are they just links?

 

[Moon_Fire]

Thanks a lot for the pictures and the Resistance measurement!

 

[PhilHornby]

Do you need anything else, or can I re-assemble the hub?

 

[Moon_Fire]

You are very kind sir and i am in debt to you. I hope I won't need any more help regarding this issue.
I do however have a dilemma. If i want to connect my Drayton hub to a regular boiler that only serves as heating what ports should I use?
It failed when I used ports 1&2. So the correct answer is 1&3?

 

[PhilHornby]

If i want to connect my Drayton hub to a regular boiler that only serves as heating what ports should I use?
It failed when I used ports 1&2. So the correct answer is 1&3?

On that hub, Pin 4 goes LIVE (230VAC) when there is demand for heat. So I would say just PIN 4 and Neutral direct to the Boiler&Pump. (Assuming there are no motorised valves that need to be energised).

I think

PIN 1 goes LIVE when HW is OFF
PIN 2 goes LIVE when CH is OFF
PIN 3 goes LIVE when HW is ON
PIN 4 goes LIVE when CH is ON

 

[Moon_Fire]

Hey Phil thanks again for your time and effort.
I think that my Heating boiler needs something else than this hub provides. As in my previous Thermostat had 4 pins: The regular N,L and 2 extra pins. If the thermostat fell below the required heat measurement all the thermostat did was to short the pins 3 and 4. That what my Boiler needs. It requries that the 2 extra pins (i think they're 5V or so, low voltage) are set to "connected" with each other. I tried with a single wire that came out of port 1 and enters the port 2 and the heating starts.
Does the wiser hub run this kind of operation?

 

[Moon_Fire]

PIN 1 goes LIVE when HW is OFF
PIN 2 goes LIVE when CH is OFF
PIN 3 goes LIVE when HW is ON
PIN 4 goes LIVE when CH is ON

Also can you please explain what HW and CH mean?
I think there is some piece of info that I'm missing

 

[PhilHornby]

As in my previous Thermostat had 4 pins: The regular N,L and 2 extra pins. If the thermostat fell below the required heat measurement all the thermostat did was to short the pins 3 and 4. That what my Boiler needs. It requries that the 2 extra pins (i think they're 5V or so, low voltage) are set to "connected" with each other.

The WT714R (one channel) hub does what you want. It has relay connections that are 'voltage free', so it's just a switch.
Pins 1 and 3 on that hub form a simple switch, that closes when heat is demanded.

The WT724R (two channel) hub has one side of each relay contact internally connected to the Live 230VAC. It would not be easy to modify it, since it is a multi-layer PCB and the related tracks are internal, within the board. You'd have to drill holes to try and sever the link. Not a simple task...

You could use the 230VAC output of the WT724R to operate an external (mains-powered) relay, and connect that relay's switch to your boiler.

Not a cheap option though:

DIN Rail mounted 'contactor'

or

Mains Relay

You would need some sort of enclosure to mount them in.


Maybe there's an alternative though.

Link your boiler's thermostat inputs together (so that it would be permanently ON), then disconnect the boiler's main's Live feed and connect it to Pin 4 on the WT724R instead. When the Wiser hub calls for heat, 230VAC would power the boiler directly and since its thermostat inputs are shorted, it should power up.

(Assuming it's a gas or oil boiler (because the Wiser hub's relays are rated at 5A max.))

Also can you please explain what HW and CH mean?

HW = Hot Water
CH = Central Heating (Room / 'Space' Heating)

 

[Moon_Fire]

Huuuge thanks with the explanations! You totally lit my room now. I get what you're saying.
But i have another idea: what if I could use a regular relay that I connect to the Board and use the relay as an intermediary between the board and the heat boiler. So I can separate the 230V AC circuit and the other one that gets used just for the short/switch?

 

[PhilHornby]

I had a thought on my idea about controlling the boiler directly via Pin 4.

Though it should work for old gas boilers and any oil boiler, new gas boilers contain a lot more electronics and may not like being frequently power-cycled; they may go through a lengthy initialisation. (I don't have one, so I don't know).

what if I could use a regular relay that I connect to the Board and use the relay as an intermediary between the board and the heat boiler.

That sounds technically plausible, but I think it might prove quite tricky/fiddly in practice (just from a soldering point of view). There's a possibility that the drive transistor could be overloaded, if the old relay is left in-situ as well. The data sheet for the existing relays is HERE (the 24VDC version).

Another idea:

The Wiser output feed would normally drive a motorised valve. (I don't know if these are common in Romania), but they have a small motor that turns a valve and when it reaches a certain position, a microswitch is activated. That microswitch is normally used to send power to the boiler / pump, rather than the Wiser itself.

You can buy replacement actuators for these valves (containing just the motor and switch(es). There are lots of different brands, but this Honeywell version was one of the cheaper ones I found. There is a datasheet (for the entire valve) HERE. (You wouldn't need the actual valve part).

Electrically it's inferior to the other relays I linked to (too many moving parts!), but at least it's the sort of thing you might expect to find connected to a boiler

 

[Moon_Fire]

Ok I think you have helped me understand what this Hub can and cannot do!
But let's talk now on the subject. My boiler which is does Heating and Hot Water is called Buderus Logamax GB072 V2 which I can't find an user manual in english for you to read.
I'm going to speak to a friend of mine that knows his way around this stuff and work a solution. But if it gets more complicated I might just give up and buy the WT714R you mentioned above.