problem with Dimplex Duo300n heaters

[Agaxyz]

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.
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• 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).
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• 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.
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• 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.

 

[Avo Mk8]

You are not alone, there have been a few posts on this forum with people having such problems - search 'Dimplex Duo'

Is there a separate E7 night rate feed to your heaters from a dedicated off-peak consumer unit? If so, ensure that's 'on' and the individual breakers/ fuses are OK ! Since several heaters suffer from the same problem, I'm inclined to think there may be a supply or other common issue. An electrician would be able to check the off-peak feed to the heaters.

Some parts, such as thermostats and elements, are still available, eg through eBay (!), so if you don't feel competent to do the electrical detective work, you may be able to find someone willing to at least have a look.

I'm afraid the chances of diagnosing the cause of such faults over the web may be pretty slim

 

[Agaxyz]

You are not alone, there have been a few posts on this forum with people having such problems - search 'Dimplex Duo'

Is there a separate E7 night rate feed to your heaters from a dedicated off-peak consumer unit? If so, ensure that's 'on' and the individual breakers/ fuses are OK ! Since several heaters suffer from the same problem, I'm inclined to think there may be a supply or other common issue. An electrician would be able to check the off-peak feed to the heaters.

Some parts, such as thermostats and elements, are still available, eg through eBay (!), so if you don't feel competent to do the electrical detective work, you may be able to find someone willing to at least have a look.

I'm afraid the chances of diagnosing the cause of such faults over the web may be pretty slim

Thank you for the tip in relation to "Dimplex Duo" and all the other advice. I would say there is a separate E7 feed. Will probably have to ask an electrician to look at it, thought I was also advised that maybe I should put both the heating for the whole day and whole night on max and see what will happen than...? Would you say that if I start control them again via the main control panel they might start working? Is is possible that turning this main control panel off a while ago, might have triggered something and all of them stopped working?

 

[Avo Mk8]

Thank you for the tip in relation to "Dimplex Duo" and all the other advice. I would say there is a separate E7 feed. Will probably have to ask an electrician to look at it, thought I was also advised that maybe I should put both the heating for the whole day and whole night on max and see what will happen than...? Would you say that if I start control them again via the main control panel they might start working? Is is possible that turning this main control panel off a while ago, might have triggered something and all of them stopped working?

It is worth trying the main control panel. I believe these heaters are about 15 years old, and it is possible that turning the power off to the controller (if that's what you did) has caused a backup battery in it to give up, or some electronic fault, but that's unlikely.
I don't think playing with combinations of settings will achieve anything.

You are aware that to charge up a storage heater, ie to heat up the storage medium, it has to be on for quite a few hours before it's able to give out much heat (but that also relies on the controls working of course!).

 

[Agaxyz]

It is worth trying the main control panel. I believe these heaters are about 15 years old, and it is possible that turning the power off to the controller (if that's what you did) has caused a backup battery in it to give up, or some electronic fault, but that's unlikely.
I don't think playing with combinations of settings will achieve anything.

You are aware that to charge up a storage heater, ie to heat up the storage medium, it has to be on for quite a few hours before it's able to give out much heat (but that also relies on the controls working of course!).

The building was built about 11/12 years ago so this is how old the heaters here are. If turning the main RXPW4 control panel off might have caused a back up battery in it to give up, would it be possible for this battery to start working again just by turning this panel on again? Sorry, again I'm not electrician so not sure how it works. From my understanding all those heaters should work as an individual units, without being connected or controlled via RXPW4. And this is what heater no 1 does.

 

[Avo Mk8]

The building was built about 11/12 years ago so this is how old the heaters here are. If turning the main RXPW4 control panel off might have caused a back up battery in it to give up, would it be possible for this battery to start working again just by turning this panel on again? Sorry, again I'm not electrician so not sure how it works

I don't even know for sure if there is such a battery In the unit. I was just suggesting a possibility. And indeed after power is restored the battery should charge up and everything work again. But 10 year old batteries can be unpredictable.

I agree the units should work by themselves. I was thinking that if several of them were suffering from similar symptoms, it migt be from some outside influence, like a problem with E7, rather than each unit having developed an individual fault.

I don't have anything else to suggest. If you can satisfy yourself that both the normal rate supply and the off-peak supply are present at the heaters (assuming that is the intended arrangement), then you need help from someone experienced at repairing such appliances.

 

[Agaxyz]

I don't even know for sure if there is such a battery In the unit. I was just suggesting a possibility. And indeed after power is restored the battery should charge up and everything work again. But 10 year old batteries can be unpredictable.

I agree the units should work by themselves. I was thinking that if several of them were suffering from similar symptoms, it migt be from some outside influence, like a problem with E7, rather than each unit having developed an individual fault.

I don't have anything else to suggest. If you can satisfy yourself that both the normal rate supply and the off-peak supply are present at the heaters (assuming that is the intended arrangement), then you need help from someone experienced at repairing such appliances.

Ok, thank you for trying to help. I just checked with the previous tenants and previously all heaters including the water immersion heater were controlled by this panel. So now this one heater in the corridor, close to water heater works ( the water heater also works) and the rest not, probably there must be some kind of connection between those not working on night rate heater or just by bizzare luck they stopped working at the same time, rather strange - I will talk to the electrician. But the last question I have is: as mentioned previously once I waited till the electricity night rate starts (for an example lets assume it starts at midnight) and turn the day heating on at 1am on all 3 heaters. They did not work. Lets call this situation scenario 1. So last night I turned them on an hour before the night rate starts (so lets say at 23:00), so they were working on a day system, and I kept this day system on when the night rate started at midnight. Somehow they kept on heating. Next, I wanted to see if maybe they kicked off and started to heat on the night rate so about 01:15 I turn the day heating off and ...they stopped heating... (let's call it scenario 2) I just do not understand how come they did not heat up on the day system in scenario 1 but kept on heating on a day rate in scenario 2 - the only difference being that in scenario 2 day heating system was on when the night rate and night heating system should have started. I kind of thought that they would or should turn themselves off automatically when the night heating system kicks in. Would this normally happen, if their night storage system was working properly? Or if the day heating system is on when the night heating should start, the day heating will also stays on?

 

[Avo Mk8]

Ok, thank you for trying to help. I just checked with the previous tenants and previously all heaters including the water immersion heater were controlled by this panel. So now this one heater in the corridor, close to water heater works ( the water heater also works) and the rest not, probably there must be some kind of connection between those not working on night rate heater or just by bizzare luck they stopped working at the same time, rather strange - I will talk to the electrician. But the last question I have is: as mentioned previously once I waited till the electricity night rate starts (for an example lets assume it starts at midnight) and turn the day heating on at 1am on all 3 heaters. They did not work. Lets call this situation scenario 1. So last night I turned them on an hour before the night rate starts (so lets say at 23:00), so they were working on a day system, and I kept this day system on when the night rate started at midnight. Somehow they kept on heating. Next, I wanted to see if maybe they kicked off and started to heat on the night rate so about 01:15 I turn the day heating off and ...they stopped heating... (let's call it scenario 2) I just do not understand how come they did not heat up on the day system in scenario 1 but kept on heating on a day rate in scenario 2 - the only difference being that in scenario 2 day heating system was on when the night rate and night heating system should have started. I kind of thought that they would or should turn themselves off automatically when the night heating system kicks in. Would this normally happen, if their night storage system was working properly? Or if the day heating system is on when the night heating should start, the day heating will also stays on?

Hi
Presumably you have the instruction leaflets for the radiator and the control panel?
When you say 'kept on heating' and 'stopped heating' you are presumably referring to what the indicator lights are showing?
It seems the controls are doing something, even if we can't make sense of it!

When it comes to actual heat output, the only element you would be aware of being hot in the short term is the radiant one. The off peak element is buried in the thermal store, so it would take quite a while for heat to appear from that.

I also remembered there is a thermal fuse for the storage part of the heater, so there is a possible explanation for the stored heat not working, although if the heaters worked for the previous owners it seems very unlikely that three units would all suffer from that.

There's lots of info on the web on these units, and it seems spares are still available (not made by Dimplex, but supported by them I think)

https://www.dimplex.co.uk/sites/default/files/assets//DuoHeat_N_Installation_Instructions_Issue_5.pdf

Module pcb REPAIR SERVICE Storage heater Dimplex Duoheat 300n 330 etc N 87389B | eBay

Any Storage Heater. Brief Fault Symptoms. This is a Repair Service. Test and repair of your module/pcb What you need to do. Quality House. Quality Electronic Repairs.

www.ebay.co.uk

PS That link is not because I think your module is faulty - it was just to let you know in case such parts turn out to need attention!

 

[Agaxyz]

Hi
Presumably you have the instruction leaflets for the radiator and the control panel?
When you say 'kept on heating' and 'stopped heating' you are presumably referring to what the indicator lights are showing?
It seems the controls are doing something, even if we can't make sense of it!

When it comes to actual heat output, the only element you would be aware of being hot in the short term is the radiant one. The off peak element is buried in the thermal store, so it would take quite a while for heat to appear from that.

I also remembered there is a thermal fuse for the storage part of the heater, so there is a possible explanation for the stored heat not working, although if the heaters worked for the previous owners it seems very unlikely that three units would all suffer from that.

There's lots of info on the web on these units, and it seems spares are still available (not made by Dimplex, but supported by them I think)

https://www.dimplex.co.uk/sites/default/files/assets//DuoHeat_N_Installation_Instructions_Issue_5.pdf

Module pcb REPAIR SERVICE Storage heater Dimplex Duoheat 300n 330 etc N 87389B | eBay

Any Storage Heater. Brief Fault Symptoms. This is a Repair Service. Test and repair of your module/pcb What you need to do. Quality House. Quality Electronic Repairs.

www.ebay.co.uk

PS That link is not because I think your module is faulty - it was just to let you know in case such parts turn out to need attention!

In terms of 'kept on heating' and 'stopped heating' - yes in relation to the situation 1 I turned the day panel on, so the days lights/indicators were on, it was 1am but the heat was not produced. The night rates for than example starts at midnight. In terms of situation 2 the day lights/indicators were on from 23:00ish till 1:15ish in the morning and as long as they were on the heat was produced. Once I turned the day lights off the heat was stopped being produced. I do have instruction etc but there is nothing about problem solving/troubleshooting. I assume if I call the electrician and explain the problem over the phone, when he/she comes they would have at least those thermal fuses or some parts to try to solve this on the spot, if possible? Not sure what equipments and parts the electricians on avage carry with them. Again thank you for your help.

 

[Avo Mk8]

In terms of 'kept on heating' and 'stopped heating' - yes in relation to the situation 1 I turned the day panel on, so the days lights/indicators were on, it was 1am but the heat was not produced. The night rates for than example starts at midnight. In terms of situation 2 the day lights/indicators were on from 23:00ish till 1:15ish in the morning and as long as they were on the heat was produced. Once I turned the day lights off the heat was stopped being produced. I do have instruction etc but there is nothing about problem solving/troubleshooting. I assume if I call the electrician and explain the problem over the phone, when he/she comes they would have at least those thermal fuses or some parts to try to solve this on the spot, if possible? Not sure what equipments and parts the electricians on avage carry with them. Again thank you for your help.

Thanks for the explanation.

One thing I'm not sure about is what happens to the local controls when the pilot wire is connected to the RXPW4 controller.
You mentioned the one heater that is not connected to the controller works fine.
I wondered if the heaters with their pilot wire to the controller were overridden by the settings of the controller, or maybe the controller has to be on a particular setting for the heater buttons to work. Just a thought.
It might be worth the electrician disconnecting a pilot wire (it's at mains voltage!) and seeing if that changes the behaviour of that heater!