Drayton Flowshare relay

[Robert Tyrrell]

Can anyone tell me what the purpose of the Drayton Flowshare Relay RB2 is?
I was called to a property today only to find that there's no power from said relay to the boiler and as I can't find one at a decent price I'd like to remove it but I'm not too sure if it's practical to do so?

 

[Mike Jackson]

You also need to replace the 3 port valve if you remove the relay.

wiring

 

[Robert Tyrrell]

You also need to replace the 3 port valve if you remove the relay.

wiring

Thanks for that but why do I need to replace the valve, are they linked in some way?
i didn't get a chance to look in the airing cupboard 🙂

 

[Mike Jackson]

The valve used will have the TA/M4 actuator which doesn't incorporate an auxiliary switch to activate the boiler. The boiler is switched from within the RB2 relay box. There will also be no HW off wired from the programmer or the cylinder stat. It is apparently possible to replace the RB2 with a double pole changeover relay (DPDT) following the wiring diagram inside the lid of the RB2 but I've never done this so don't know how easy it is.

 

[Robert Tyrrell]

The valve used will have the TA/M4 actuator which doesn't incorporate an auxiliary switch to activate the boiler. The boiler is switched from within the RB2 relay box. There will also be no HW off wired from the programmer or the cylinder stat. It is apparently possible to replace the RB2 with a double pole changeover relay (DPDT) following the wiring diagram inside the lid of the RB2 but I've never done this so don't know how easy it is.

I realise that this is just wishful thinking but is there any chance that I could get a replacement actuator for the valve that works like the 4073A?

 

[Mike Jackson]

As far as I'm aware none of the Drayton TA range have both mid position and auxiliary switch.

 

[Robert Tyrrell]

Thanks Mike, what I actually meant, although I didn't explain it properly, was - can you replace the actuator with a normal one like the honeywell ones (Without the reliance on the relay). It's a moot point now in any case as Ive located a replacement through Plumbcenter.
The tenant has just texted me to say that the heating has come on now, so as it was definitely not working before, and it's been sporadic in it's activity, I'm presuming that the relay is definitely faulty.
I'm not good at electronics so if you, or anyone else knows how to check the relay using a multimeter I'd appreciate the information just in case I get this again 🙂