Sauter Detach Motorised Valves

Detach 3-port valve

In a traditional central heating system - where you have a boiler and a hot water cylinder i.e. not a Combi boiler - the boiler itself has no idea what it is heating. All it knows is that cool water comes into it and - with luck - hot water leaves. Where that hot water goes is none of its concern.

The same cannot be said for the homeowner, who is often very concerned as to where all that fully-paid-for hot water is going, so most CH systems will have within them one or more ‘motorised valves’. These are usually hidden in the airing cupboard next to the hot water cylinder and they control what gets hot; the radiators, the hot water cylinder, or both.

To perform this vital function they contain a number of moving parts and the sad thing about moving parts, especially ones constantly immersed in water, is that sooner or later they give up the ghost and expire, usually in the dead of winter when they are needed most. As such they are one of the most frequently replaced parts of a central heating system.

We went through the process of how to replace these valves within the Haynes Home Plumbing Manual but at the time I had never heard of the “Detach” motorised valves by Sauter, possibly because they weren’t sold in the UK at the time. This was a shame because they seem to be very good valves that offer real benefits to plumbers and DIY enthusiasts alike.

First off they come with a detachable lead. This doesn’t sound like much but it’s the wiring that is often the most daunting aspect of replacing one of these valves. Quite why, in the vast decades that motorised valves have been around, no one else had ever thought of inventing a lead that could just be unplugged is one of life’s great mysteries, but fortunately Sauter did make that breakthrough and life is now just that little bit easier as a result.

Of course this is of little help if you’re putting a Sauter valve in for the first time but at least any subsequent repairs and replacements will be considerably easier.

Another nice point is the easy-to-detach head. This is where the actual motor – often called an actuator – resides and it is often this part that dies well before the main valve. As such it’s very handy if this can be removed quickly and easily. Fortunately most manufacturers offer this feature these days - Honeywell being the notable exception. 

Bizarrely, the Sauter valve doesn’t just rely on a nice simple button to remove the valve but insists that you remove a small screw first. This seems unnecessarily inconvenient bearing in mind that these valves are usually set in fairly cramped conditions, but there you are.

Finally, this is one of the few valves that actually tells you what it’s doing. Rather than listening for the sound of the motor, or trying to catch a glimpse of the lever arm moving this valve has a two lovely little lights, one labelled CH and the other HW. Again, a really simple improvement that was somehow beyond the wit of every other manufacturer.

To put the icing on the cake, they are also pretty well priced and rumour has it that they are looking to develop heads that will fit onto other manufacturers valve bodies, so you can get all the benefits of the Sauter Detach without the hassle of replacing the old valve completely.

All in all a very welcome product.