Salus RT500RF supply fuse rating

[phil001]

Morning all,

I am replacing an old thermostat with a RT500RF this weekend.

I happen to have an unused switched fused spur very close to the thermostat location so should be an easy swap.

Just a quick question - what fuse rating should i use? (the spur will only be feeding the thermostat, nothing else)

The manual states 13A maximum, but that seems a bit large to me?!

Thanks

 

[Agile]

The correct fuse rating would be 1A but they are not so easy to find so use 3A.

But the receiver unit is located ( usually ) beside the boiler and its normal for the supply to the RX unit to be obtained from the boiler.

Tony

 

[phil001]

thanks for the reply, ill go with a 3A then.

I may move it to beside the boiler when i next decorate as it will leave cable and mounting holes in the wall if i move it now which i can cover with the new unit

Thanks again

 

[Agile]

You have not mentioned the boiler model.

But is it an older one with 230v switched live input and you have a wall stat with a live, neutral and switched live wires back to the boiler?

In that case you can power the RX unit from the live and neutral and use it to send the switched live to the boiler.

Thus not needing any further supply connections to the RX unit.

Tony Glazier

 

[phil001]

its a Biasi Riva Compact (i think)

Its just a switched pair at the thermostat, no 230v.

Cheers

 

[Agile]

Are you quite sure there is no neutral at the stat?

Most older stats required a neutral connection to operate a heat anticipator.

One side of the Biasi connections is actually a live.

Tony

 

[phil001]

Untitled

• phil001
• 10 Oct 2014
• 1

Untitled

• phil001
• 10 Oct 2014
• 1

got a feeling it was bodged in a bit to be honest, it was in when we moved there.

I can see where there should have been a neutral as you say.

One of these definitely live then? What voltage?

thanks