Relacing Faulty Salus rt300rf Wireless Thermostat

3 Mar 2008
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United Kingdom
The thermostat (receiver) on my RT300RF is faulty, I can get a same for same replacement so I thought, locally. However when comparing the wiring diagrams on Salus web page, the latest model appears different, what I need to know is the equivalent wiring on the newer model compared to the faulty model.

The faulty stat shows the following wiring.

SL (Off) - Heat Off*

L – Live

SL (On) - Heat On

N – Neutral

The newer model shows the following.

1 NO Normally Open [N/O]

2 COM Linked Live feed (230V AC heating applications only)

3 L Live feed (230V AC)

4 N Neutral

The L & N are obvious, but would appreciate explanation as to what wiring on the new model relates to those on the faulty model.

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Is there not a comm on the faulty one??
NO is SL on
There is a COM, but is only used when the unit is configured as Volt Free, if Volt Free a Link must be removed, the unit is configured as 230v which is the default, and has been wired as such. As the unit has worked fine for 4 years.
bit unsure how its been wired but what you should have on the old one for a 240vac system is live and neutral connected, live to the common and then SL on connected back to the boiler, NO on your new salus. regardless of weather its 240v or low voltage something needs to go into the common so the power can then be put back to boiler to switch it on. manufacturer says to connect this way, If its 240vac

Permanent live goes to common
Neutral to neutral
Link common to live
SL on then back to boiler heating on terminal

if its low voltage:
Permanent live 240v to Live
Low voltage feed from boiler to Common
SL ON back to low voltage return (heating on) at boiler.
Post up the type of boiler, and we can work out what needs to be done.
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Sorry not to reply sooner.
I should in my originall post mentioned that the "fault" was the thermostat was switching off the c/h before the set temp was reached, a lengthy session with Salus Support indicated a faulty unit. But I was not to sure, so I carried out the following checks.

Swiched Off all other Wireless devices in the house incase there was interference . Still the thermostat behaved erratic.

Changed the RF code (Dips and jumpers), to another code, just in case another wireless thermostat within the 60m max range was causing the problem. Bingo problem solved, although I did have to Reset the thermostat which may have been prob.

Thanks anyway for your info, I have also manged to obtain the identical Model on Ebay, so if prob recurs will swap it out.

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