Discuss Help with replacing this discontinued Dimplex Programmer? in the Electrical Forum area at ElectriciansForums.net

Welcome to ElectriciansForums.net - The American Electrical Advice Forum
Head straight to the main forums to chat by click here:   American Electrical Advice Forum

Reaction score
0
Hey everyone,

My flat has all electric panel heating and uses a Dimplex PW4 programmer that has died. It's also discontinued, i can see why as you need to be a rocket scientist to set it anyway.

Help with replacing this discontinued Dimplex Programmer? 20201024_225343 - EletriciansForums.net
Help with replacing this discontinued Dimplex Programmer? 20201024_225350 - EletriciansForums.net

As this is just a switched live switch am i right in assuming it could simply be replaced with any other range of programmer such as Nest, hive etc even though it's for electric panel heating and not gas?

Help with replacing this discontinued Dimplex Programmer? Screenshot 2020-10-26 at 00.59.26 - EletriciansForums.net
 
I'd also forgot to mention that there's only one pilot wire in contact 1 and nothing in 2 3 or 4 so doesn't look like it's zoned off.
 
I've seen 3 of these now, all in Barratt flats installed about 2005. Every single one has failed in the same way, with a bulging component on the board - so they clearly weren't well designed in the first place.

Shameful that they don't offer a suitable replacement now though and try to upsell you to their latest expensive system.

I just disconnected them as they didn't seem to offer much benefit, even if you could work them out. From the little research I did, there is just a single live pilot wire from it to all the heaters and the storage heaters had a 4 core input so that the thermostat can override the convection controls.

The 2 recent ones I've seen even had them wired as far as the bathroom heaters so that you could turn those on too (Not actually connected) which mean 3 switches for every storage heater and 2 for non-storage - no surprise that the tenants never worked out how to use them.

In the refurb I did I replaced the radiators with Q-Rad models which are no longer storage, but probably more suitable for tenants who are out at work most of the day.
 
I've seen 3 of these now, all in Barratt flats installed about 2005. Every single one has failed in the same way, with a bulging component on the board - so they clearly weren't well designed in the first place.

Shameful that they don't offer a suitable replacement now though and try to upsell you to their latest expensive system.

I just disconnected them as they didn't seem to offer much benefit, even if you could work them out. From the little research I did, there is just a single live pilot wire from it to all the heaters and the storage heaters had a 4 core input so that the thermostat can override the convection controls.

The 2 recent ones I've seen even had them wired as far as the bathroom heaters so that you could turn those on too (Not actually connected) which mean 3 switches for every storage heater and 2 for non-storage - no surprise that the tenants never worked out how to use them.

In the refurb I did I replaced the radiators with Q-Rad models which are no longer storage, but probably more suitable for tenants who are out at work most of the day.
Ah that makes sense. Yeah I'd basically just left it on continuous as i couldn't work it out.
These are the radiators in the flat. Can't get any to work without replacing this programmer which is annoying as I'd never used the programmer anyway.

Help with replacing this discontinued Dimplex Programmer? 20201026_112536 - EletriciansForums.netHelp with replacing this discontinued Dimplex Programmer? 20201026_121312 - EletriciansForums.net

So as this zoned pilot wire just seems to be a switched live when the programmer calls for heat I'm guessing most standard programmers should work without the need for another pointless zoned programmer?
 
Looks like a slightly different setup - maybe they've been replaced at some point? Is the first heater in the lounge or a bedroom?

The ones I've seen had the pilot wire running to the storage heaters (off peak and on peak supply plus a switch for the programmer feed) and bedroom heaters (on peak supply plus switch for programmer feed).

So they could be used in manual mode regardless of the programmer working or not. The feed to the heaters was 4 core with a live from the heating circuit and a live from the progammer, so perhaps someone has replaced them in your case and wired to the programmer feed, rather than the switched on peak feed .

The programmer had a normal back box behind it in my cases, so you could just replace it with a fused spur and just use as a switch - or I guess any programmer should work, though it might depend on what load it is actually switching.

I've just inspected two identical flats in the same block with them - One of them had the feed for the programmer on it's own circuit, the other was fed from the bedroom heater circuit - so make of that what you will.

Might be worth getting someone to work out the wiring as there may be a better solution to avoid using the programmer completely and keep each room separate.
 
Looks like a slightly different setup - maybe they've been replaced at some point? Is the first heater in the lounge or a bedroom?

The ones I've seen had the pilot wire running to the storage heaters (off peak and on peak supply plus a switch for the programmer feed) and bedroom heaters (on peak supply plus switch for programmer feed).

So they could be used in manual mode regardless of the programmer working or not. The feed to the heaters was 4 core with a live from the heating circuit and a live from the progammer, so perhaps someone has replaced them in your case and wired to the programmer feed, rather than the switched on peak feed .

The programmer had a normal back box behind it in my cases, so you could just replace it with a fused spur and just use as a switch - or I guess any programmer should work, though it might depend on what load it is actually switching.

I've just inspected two identical flats in the same block with them - One of them had the feed for the programmer on it's own circuit, the other was fed from the bedroom heater circuit - so make of that what you will.

Might be worth getting someone to work out the wiring as there may be a better solution to avoid using the programmer completely and keep each room separate.
Yeah it's a strange one. Dimplex were helpful. They now say you can't replace the programmer as I'd now need to replace every electric heater to all have their own thermostat and programmer for each one.
 
Are these controllers switched live to the outputs? IIRC they are switched neutral, but my memory could be failing.
 
Yeah it's a strange one. Dimplex were helpful. They now say you can't replace the programmer as I'd now need to replace every electric heater to all have their own thermostat and programmer for each one.
Yes, and even the simplest wall heaters are expensive, at least partly because of the Lot20 requirements.

Just replaced the storage heaters in one of the flats with Dimplex QRad radiators, which cost (though a lot less than replacement storage heaters), but do have their own thermostat/programmer and look quite nice.
 
Are these controllers switched live to the outputs? IIRC they are switched neutral, but my memory could be failing.
The one's I've seen have switched live pilot wire, through a 10A switch, and utilised the local on peak neutral for each heater, but there may be different ones.

This is a pic from the first one I encountered earlier in the year, which was only 2 zone

Help with replacing this discontinued Dimplex Programmer? Dimplex - EletriciansForums.net
 
I get the impression from the installation manual that the pilot wire is a communications link (despite being mains voltage) as it seems to be able to instigate different functions. Maybe that's why you can't just use a normal programmer.

How about replacing yours with a one channel version:
https://www.ebay.co.uk/itm/Dimplex-...371768&hash=item3fe53a2200:g:p90AAOSw1NxfDy~O
 
There's definitely a market for a simple on/off panel heater that's controlled by a central programmer. The programmer would take a feed from a thermostat located in each room. If this could have an App that runs alongside it, so much the better.

Sadly, from what I've read... I think Lot20 rules prohibit this.
 
Hi Karl
As I suggested in post #12, I believe the 'pilot wire' carries an encoded signal. I don't believe it's just zero or 230v depending on whether the heater should be on or not. But I have been unable to find any explanation of the pilot wire signalling protocol, so I can't back up this hunch!
Personally I don't think you can use a current programmer to activate the old Dimplex units as originally intended, but I'd be happy to be proved wrong.
 
Have any of you got pictures of the inside of the failed units? It's probably just a capacitor gone down. If anyone wants to send me a failed unit I'll take a look and see if they can be repaired.
 
The 'pilot wire' signalling protocol seems to have been a French development, specified in a GIFAM standard. I suspect finally dropped in the UK because the pilot signal seems to be referenced to the Economy 7 Neutral, giving a risk of 'borrowed neutral' problems.
After a bit of Googling I've convinced myself there's little point in trying to control a pilot wire heater from a typical on/off programmer or smart controller. At best all one can do is to switch the heater between 'comfort' and 'Eco' by applying mains to the pilot wire, unless one starts designing something with diodes!

I did find a Test House spec (in English) which has as an appendix describing the pilot wire protocol (but in French!), page 24, if anyone is interested!

So I fear anyone with Dimplex pilot wire heaters are stuck with keeping, mending or replacing the existing Dimplex 'programmer' (some models still available), or changing the heaters.

Help with replacing this discontinued Dimplex Programmer? 1A2F0C67-0146-4728-8CF7-763EF5539AB8 - EletriciansForums.net
 
Have any of you got pictures of the inside of the failed units? It's probably just a capacitor gone down. If anyone wants to send me a failed unit I'll take a look and see if they can be repaired.
This is one I took at the most recent job with one - Not a great pic I'm afraid - hard to see but there is a bulge in the circled area - and it's been the same on every one I've seen (4 or 5 now) - The first one I ran into on a job last year was even clearer with a melted/burn mark in the same place.


Help with replacing this discontinued Dimplex Programmer? IMG_20210205_170157 - Copy - EletriciansForums.net

I left the unit this pic is of on the job unfortunately and fairly sure I binned the one I did take from a job some months back, but I'll have a rummage. If I take one out again in the future I'll keep one for you.
 
Wonder if transformer has overheated and the internal thermal fuse gone?
 

Reply to Help with replacing this discontinued Dimplex Programmer? in the Electrical Forum area at ElectriciansForums.net

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electrical Goods - Electrical Tools - Brand Names Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

Electrical Forum

Welcome to the Electrical Forum at ElectriciansForums.net. The friendliest electrical forum online. General electrical questions and answers can be found in the electrical forum.
This website was designed, optimised and is hosted by Untold Media. Operating under the name Untold Media since 2001.
Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock