Salus RT500RF Connection Issue / Vokera Compact HE boiler.

[GeorgeyV]

Hi all -

We have inherited a problem with the thermostat in our house.
We have a Vokera Compact HE boiler which functions absolute fine, using the timer on the front (which is a pain) - we have a Salus RT500F which has never worked, I've not been able to connect it (red light always on no matter what procedure I have followed) A plumber who came to service noticed is only connected to the power at the boiler end (pic attached below) so we have 2 loose wires which connect to the Salus Receiver next to the boiler, and then 2 black wires which must be original to the boiler.

https://ibb.co/f1CkOG

I'm thinking there was a problem with the thermostat in the past so this has been done as a temp bodge - does it sound familiar to anyone?

I am considering a replacement of the same Salus Unit (though a newer model, our receiver looks different to the ones currently available) as they're not too expensive and they look fairly simple to fit - I'm fairly competent and don't feel phased with fitting, but troubleshooting the existing set up is a bit beyond my grasp!

Cheers all.

 

[stem]

I can't see your photos unfortunately, but if the red light is always 'on' then the remote thermostat isn't switching the receiver off.

The first thing I would try, is changing the RF address code setting of the receiver, pairing it with the thermostat and doing a reset. [The instructions tell you how to do this if you don't have them, you can download them here.]

The reason for changing the RF address code setting. This is because I have found several of these that have been left at their factory settings and being switched by a Salus thermostat in a neighbouring property. There is no point in going any further until the thermostat is communicating with the receiver and switching it receiver on and off.

 

[GeorgeyV]

Thanks - super helpful.

Will do this when I get home and report back.

P.S does this link work for the photo?
https://ibb.co/f1CkOG

 

[stem]

Yes I can see this with your above link.



But unfortunately it doesn't help, because the terminals are not identified and it's difficult to see what wire goes where. But as I said earlier, until the two devices are communicating, there's no point in looking at the wiring.

 

[GeorgeyV]

Thanks Stem,

Have had a look at the above: Changed the thermostat sender and receiver channels from the factory ones, reset the sender and turned the receiver back on. Still have power but no green light. The sender displayed the flickering flame but still nothing at the receiver/boiler.

As far as I can see from the receiver, the L and N are connected up as they should be, NO and COM are routed to the boiler but left unconnected. NC has no connection at all.

I'm hazarding a guess the thermostat has conked out at some point and as a bodge it's been disconnected at the boiler but left in situ.

Does this seem like it could be the case? If so am I best the replace the whole unit? It looks like my receiver is an older model, it doesn't have the same look as the others I've seen.

 

[stem]

Usually the receiver looks like this

The bottom red light shows that the unit is receiving power, and the green light above only comes on when the thermostat has switched the heating on. This unit doesn't have a NC connection, so yours as you say may be different.

However, if it isn't switching, then your theory could well be correct and would explain why it has been disconnected.