Central Heating Controls - Help!

My house has electric rads throughout, with no obvious centralised control regulation and it came with no user manual for the system. In addition, because the original owner only used it as a holiday rental, I suspect renters simply switched them on and left them on to heat the house when needed!

Now I’m living here and obviously want to keep warm over winter as economically as possible, my problem is that nowhere can I find anyone who is familiar with these controls, nor online either - even the manufacturer’s website only offers the manual for their current system.

It’s clear (photo attached) that there’s an on-off switch, a dial to give temperature gradient (but probably trial and error - and why is there a little sun on the dial?), then another switch which is apparently day (sun), night (moon) and a clock (but no way of setting any clock that I can see!).

Help - please - if anyone else has come across this system? I want heat in the morning when I get up in the colder months, but not all night!

This is my umpteenth try at posting thanks to everyone - the screen simply locks and it won’t post. Here goes yet another attempt. Thanks everyone for your advice, really appreciate it. Looks like I’ll have to resign myself to getting a tradesman in, what I dreaded most!

Peter. I forgot to say that the relays I have are rated at 2kw although when I opened one up it actually said 3kw on the actual relay . Mine operate on 1 & 2 kw stuff with no probs.

It really is great gear at give away prices considering the norm in France. I had several conversations with their helpful technical director when my transmitter screen faded after a few weeks & a replacement from the brico store did the same. He sent me a replacement which has been fine ever since. It must have been a duff lot. It's simple to wire up. I used round boxes to put the relay in & cut a square cover plate to enable the front of the relay to show. You really need to see the relay as it has a light to show if it's on & also to go through the 'pairing' system with the transmitter.

Vic - This looks like a great system. Unfortunately, the Otio site doesn't currently appear too clear about which products do what, or how to purchase them.

It seems that Castorama sells the transmitter/3 relay product for €62.90, which is about right after allowing for a bit of inflation. I'm definitely going to get a set for the cold days ahead.

Cyndy. I would have mentioned the stuff Peter did but didn’t want to muddy the waters until certain things had been established. You need to know how the rads are wired up. If they are simply connected, Live, neutral & earth without any master time control such as the Fil Pilote system it is still possible to achieve what I consider to be an excellent control strategy for all of the house using a system developed by Otio. www.otio.com. It’s very cheap, very effective & has been in use in my house since I fitted it 3 years ago. At that time I paid 59 euros for 1 transmitter & 3 wireless relays. I added more relays for other rads later. You can control lots of zones to different times using this system. It’s a simple wiring job to interpose a relay on the rad cable or plug in a relay if the rads are ‘plugged in’. The photo shows the handset control & a relay which I built in to make flush. If you want any more info. just ask

Cyndy -

Further thoughts about using the system as it stands, some of which you may have worked out already.

To get heat, the on-off switch, leftmost in the photo, should be on, and the rocker switch should be in the middle, sun, position. The thermostat wheel then controls the temperature. To cut heating entirely, just switch off.

Given what Ian has said, you could try switching the rocker switch to the moon position overnight, which shouldn't use too much electricity as the heating will only come on if the room temperature drops by about 3.5°C. This won't give you heat in advance, as only a timer can do that, but might stop it getting too cold overnight.


What you have is very similar to lots of French electric radiators, though there might be minor differences between manufacturers. However, lots of foreigners, me included, didn't bother to wire them up completely because they didn't understand how these radiators were supposed to be operated. This is what Vic is talking about with the fil pilote system, and why he's asking about the number of wires. Unfortunately, these wires are bundled inside the grey cable that is all that you see.

What you need to do is to get an electrician or handy-man(-person), taking the necessary electrical precautions, to open up the wall box and see what connections are made in there. Given the markings on your photograph, there is bound to be an extra wire, often black & known as the fil pilote, coming from the radiator. The others are typically: i. blue; ii. brown or red (but could be something else); iii. green/yellow. The latter may be missing if it's quite old. The issue is whether the extra wire, the pilot wire, is connected to a wire coming from the wall. If it isn't there is one kind of solution available, if it is there's two possible solutions.

The first solution is to fit a local timer for the radiators that you want to switch on in advance, as there doesn't appear to be the necessary wiring going back to the main switch box. There are lowish cost ways of doing this and other, more elegant but more expensive, ways.

The second solution is to trace the pilot wire connection back to the switch box and fit a central timer there.

The first solution could be carried out by an electrically competent handy-person, or an electrician, the second probably needs an electrician.

Hope this isn't too technical.

One of them has “Applimo” on the front, Alan, so I assume they’re all by the same manufacturer. I visited the Applimo website, but the only manual I could find was one for their latest models. They look, from the outside, just like the latest model and quite modern, metal panelled. The switch appears to be level for the sun symbol, back for the moon and forward for the clock. I’ve tried all settings and still can’t fathom it out. Also, as you can see on the photo,mother dial has a “frost” setting and a sun on it - but to be used in conjunction with which setting on the switch…?!

Hi Cyndy,

Is there definitely no manufacturer name visible or even a model reference? Otherwise maybe switch off the power and take the cover off to find them? If it's up to ten years old I would think it should be possible to get instructions, maybe even online.

The switch is three-way or only two-way?

I wonder whether you put the switch in a particular position and then somehow use the "wheel" to enter the settings desired under the relevant switch position?

Hello Vic. Yes, the control is on every radiator (slightly different in the bathroom heaters, but I thought I’d tackle them once I’ve got the main ones understood!). They appear to be wired in permanently and I can only see one grey wire going into the wall. There’s no timer on the main fuse board. Any help would be really appreciated.

Cyndy. Is the control you have shown on every radiator? Are the radiators wired in permanently or plugged in ? How many wires are there to each radiator & what colours are they? Do you have a timer thing in the main fuseboard ? Answers to these questions might help devise a solution. My immediate thought is that you have radiators which can be controlled by the Fil Pilote system, which could be pretty normal, but which are not if you get my drift as maybe the controller has not been fitted as part of an original control strategy. If you can answer the above I might be able to help you with a solution.

Yes, it’s a helpful start - thanks Ian! If the sun and moon set the temperature, though, I wonder why there’s a dial apparently to increase or decrease the temperature…? And does this mean I simply have to leave the rads on all the time? If so, I can’t fathom out how I get a cooler temperature once I’m in bed, but a warmer one for getting up the next day, other than keep going around the house and moving switches/dials on each rad! Aaaargh, this should be SO simple, surely?!

I found this bit of info :

"Le pictogramme représentant un soleil symbolise le mode « confort » et signifie que vous souhaitez une température confortable dans votre pièce en votre présence. En général, entre 19 et 21°C à votre choix.

Le pictogramme représentant une lune symbolise le mode « éco » et signifie que vous souhaitez réaliser des économies grâce à ce mode qui abaisse la température de -3,5°C en dessous de la température choisie en mode confort. Ce mode est idéal pour vos absences de 2 à 48h ou la nuit."

Hope this helps :)