Currently reading:
problem with Dimplex Duo300n heaters

Discuss problem with Dimplex Duo300n heaters in the UK Electrical Forum area at ElectriciansForums.net

Agaxyz

DIY
Reaction score
5
Hello, I’m not an electrician and I have a question in relation to Dimplex Duo300n.

Some background information: a couple of months ago I have moved into the property where those heaters are in place (there is 5 of them).

The people who used to live in this apartment before, used RXPW4 control panel for majority of them (they also said all heaters were working). It was end of summer when I moved in, so I switched off this central RXPW4 control panel as I did not need that much heat during the day and planned on only using the heat from the night storage.

  • One of the heaters, seems not to be previously connected to this main control panel plus it has been on all the time (even at the end of the summer) for the night storage only and it works perfectly – this heater just an example how those heaters can work.

  • The 2nd heater once I turned it on by turning all 3 switches on on the wall, had a constant buzzing noise. Well, I was told by the previous tenants that sometimes the heaters might give clicking, buzzing noises when turned on but I did not assume it might be for that long, as once I turned on that one and it was buzzing for 30 min, at the end I turned off as it must be simply broken. I do not know if it would store the heat overnight because I’m not going to leave it on with that buzzing noise for the whole night. Having said that, I did run the diagnostic on it (the link will be below) and somehow the result came as the 2nd bar from the top flashing so it should not have a problem? But this constant buzzing?

However, the most important question I have is in relation to 3 other heaters – they do not seem to store the heat overnight (even though I would set the overnight storage temperature to max or one bar below max) though they would “work” on the day tariff. The description on how they actually work is below:

  • The 3rd heater, once turned on (what I mean by that is turning on all 3 switches on the wall) is slightly buzzing for a couple of seconds. Next the noise stops. Again does not store the heat overnight. For the day heating, it starts to heat when there are 8 read bars on the heater day control panel. However, it stops heating on its own after about 10 -20 minutes, even though the temperature in the room is less than 21C. It seems to heat constantly when all 9 indicators are red. So it does not heat when there is anything between 1 to 7 red bars on the control system. The heating it provides when on level 9 is not as strong as the heating provided by heater no 3 (described below).

  • The 4th heater once turned on is quiet so this is ok. Again it does not store the heat overnight either. For the day heating, it starts to heat when there are 3 read bars on the heater control panel. However, it stops heating on its own after about 20 minutes, even though the temperature in the room is less than 21C. When I increase the heat control to 4 red bars it also heats up only for about 20 min and turns itself off. It seems to be heating constantly when there are 5 red bars on the control panel for the day heating.


  • The 5th heater, once turned on is also quiet so this is ok. Again, it does not store the heat overnight. For the day heating, it starts to heat when there are 3 read bars on the heater control panel. However, it stops heating on its own after about 50 minutes, even though the temperature in the room is less than 21C. When I increase the heat control to 4 red bars, it seems to work constantly and provides better/warmer heat at this level 4 than heater no 1 at level 9.


What I did so far to try to sort this out is below plus my questions as well:

  • I found the video how to run the diagnostic, the link is here
    , did it for all 4 heaters and all the them had the 2nd bar from the top flashing so they seem to pass, all is fine somehow? Why would they not store the heat overnight than?
  • I turned all 3 heaters (= heater no 3,4,5) off for the couple of hours and back on – no change, still do not store heat overnight
  • I turned all 3 heaters off for about 10 second and back on – no change, still do not heat overnight
  • Shall I try to turn them off and on almost immediately? Maybe this somehow will “kick start them?”
  • I thought that maybe I should set up this RXPW4 control panel so the heat comes during the night (not as a background/night system, but maybe somehow on the day system will turn itself on during the night though it will be at a night rate so still cheaper?), in that case I could heat up the flat at night. However, once I waited deep into the night when the night electrical tariff comes on and turn on a couple of bars for the day tariff on each of 3 heaters – nothing happened, they stayed cold (not surprise here as it was night not day, but it was just an idea worth trying…)

As mentioned, the previous tenants told me that all heaters worked well when they lived here. It does seem a bit odd that 3 of them suddenly stopped working properly by not even storing the heat overnight….

I was also told that it might sound like the room temperature has a fault however Dimplex Heater no longer making parts for this heater (those heaters were discontinued). Additionally, I was told that there might a loose connection or they might need a heater full replacement (I cannot afford this).

Would anybody have any better idea what the problem/s might be for each of those heaters? What might help, what I might still try to do? Would calling an electrician to look at in person help if there are not parts for those heaters?

Thank you very, very much for reading this whole story. Hopefully there will a solution to all of this.
 
Just a question, is it safe to take the module out and leave the heater without it for a week or so? - not sure how long the repairs will take.
You must isolate the heater, ie turn it off on the wall or fusebox before removing the module, and I suggest leaving the heater switched off while it's being repaired. No harm will come to it if you do that.
Disconnect the leads at the module, remembering where they go! Photo's are useful. Don't send leads with the module as (accidentally) you may not get them back!
 
One more question: on the top (inside) the heater Dimple duo300n there are those two small parts :

1. Over Temperature Cut-Out

2. Smarty & Manual Reset - it seems on some websites it is also called "limit thermostat"

Could someone please tell me if either of them is not working or both of them are not working, how would the heater perform in that situation (if at all)? For example if no 1 that is "Over Temperature Cut-Out" is broken but not 2 is ok would the heater not heat at all? And what happens when no 2 is not working (but no 1 seems to be ok), plus what happens when both no 1 and no2 are not working?
 
Hello, I think I own everyone who read this whole story and/or provide support/advice the ending: I decided to fix all 5 pcb casue it seem none of those heaters was working correctly. First I sent 2 to be fixed, just to check, if they will be repairable at all and how they would work after the repair. Next I sent the other 3. When the electrician came it also appeared that in 2 heaters, the over temperature cut-out and limit thermostat parts were broken - they have been replaced with the "duo part". Four heaters work ok now, the 5 one works ok on the day rate but accumulates very little heat overnight. The pcbs after the repair have 1 year warranty which is great, plus one heater, once it accumulates the heat overrunning give so much heat during the day that is enough on most of the winter days. Fingers crossed all will be ok for the years to come. The end :)
 
Hello, I think I own everyone who read this whole story and/or provide support/advice the ending: I decided to fix all 5 pcb casue it seem none of those heaters was working correctly. First I sent 2 to be fixed, just to check, if they will be repairable at all and how they would work after the repair. Next I sent the other 3. When the electrician came it also appeared that in 2 heaters, the over temperature cut-out and limit thermostat parts were broken - they have been replaced with the "duo part". Four heaters work ok now, the 5 one works ok on the day rate but accumulates very little heat overnight. The pcbs after the repair have 1 year warranty which is great, plus one heater, once it accumulates the heat overrunning give so much heat during the day that is enough on most of the winter days. Fingers crossed all will be ok for the years to come. The end :)

Nice one, thanks for letting us know.
 

Reply to problem with Dimplex Duo300n heaters in the UK 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
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