Dimplex Quantum installation requirement

Debolina

I want to replace my old panel radiators with modern Dimplex Quantum storage heater. The engineer from the local Dimplex dealer  told me that, although I am on Economy 7 tariff and have a economy 7 meter, I do not have a separate night time circuit and distribution box which is required for Quantum storage heaters. So essentially my electric system is not compatible. My question is

1. If I move to a standard 24 hours tariff, would my current circuit still be inadequate for Quantam? That is, will I still need a second night time circuit?
2. If no to the previous question, does it make economic sense to run quantum on single tariff?

Gerry1

Welcome to the forum.

IIRC the Quantum can be programmed to work on a 24h supply but to shadow the E7 cheap rate times for charging.  However, you need to be absolutely sure of your meter's E7 times (beware the two hour gap after midnight in some areas).

Don't even think of running an NSH on a single tariff, it will be cripplingly expensive.  You might as well use a £15 fan heater.

danrv

Debolina said:

I want to replace my old panel radiators with modern Dimplex Quantum storage heater. The engineer from the local Dimplex dealer  told me that, although I am on Economy 7 tariff and have a economy 7 meter, I do not have a separate night time circuit and distribution box which is required for Quantum storage heaters. So essentially my electric system is not compatible. 

Similar problem here. I have Economy 10 but with a seperate night time circuit. However it’s no use for the Quantums as it powers a central warm air storage heater.
One way around it as mentioned is to time each unit and use a ring main. 
I’m not sure I’d want to do that. I’d rather leave those for regular use.
The wiring problem is holding up my Quantum installation.

matelodave

Gerry1 said:

Welcome to the forum.

IIRC the Quantum can be programmed to work on a 24h supply but to shadow the E7 cheap rate times for charging.  However, you need to be absolutely sure of your meter's E7 times (beware the two hour gap after midnight in some areas).

Don't even think of running an NSH on a single tariff, it will be cripplingly expensive.  You might as well use a £15 fan heater.

Read the Dimplex FAQ regarding a single supply - they will not even discuss it. Other manufacturer's have heaters that can be configured but it appears that Qantum's cannot (they probably could but Dimplex wont support it) https://www.dimplex.co.uk/quantum-faqs


ELNUR have the capability to run from an unrestricted E7 or E10 sungle supply - https://www.elnur.co.uk/news/single-supply-storage-heaters-what-is-required/. See page 8 of the installation manual https://www.elnur.co.uk/wp-content/uploads/2020/04/ECOMBI-HHR-Smart-Storage-Heaters.pdf

Gerry1

matelodave said:

Gerry1 said:

Welcome to the forum.

IIRC the Quantum can be programmed to work on a 24h supply but to shadow the E7 cheap rate times for charging.  However, you need to be absolutely sure of your meter's E7 times (beware the two hour gap after midnight in some areas).

Don't even think of running an NSH on a single tariff, it will be cripplingly expensive.  You might as well use a £15 fan heater.

Read the Dimplex FAQ regarding a single supply - they will not even discuss it.

You mean these instructions?

matelodave

They must have updated their instructions but not the FAQ's - apologies. I did have a look for them but obviously not hard enough.
Good info to give to the installer though if he is as useless as me 

Gerry1

matelodave said:

They must have updated their instructions but not the FAQ's - apologies. I did have a look for them but obviously not hard enough.
Good info to give to the installer though if he is as useless as me 

No problem, the customer-friendly Dimplex instructions aren't easy to find !

This single supply facility should certainly be helpful for people replacing old NSHs, e.g. those on E10, THTC, White Meter etc.

kpower7619

I wouldn't recommend fitting the quantum to a 24hour single supply, I have Eco 7 and wired mine to charge on the night tariff and my bills are still pretty high just from the heater charging at night.

Gerry1

@kpower7619 Welcome to the forum.

IF the Quantum is programmed correctly the bill will be EXACTLY the same regardless of whether it is connected to a seven hour supply.

Sounds like there's a mismatch between the programmed times and the meter times.  That can happen quite easily for several reasons, e.g.

• The Quantum is still on its default settings, and they are not appropriate;
• The E7 times in your area are not what you expect them to be;
• The meter has a clockwork timer that's drifted;
• The Quantum clock has drifted;
• GMT/BST issues;
• You have a radio teleswitch, where the times can vary by +/ 15 minutes.
• There's also the possibility that other items are adding to the bill, e.g. an E7 immersion heater with a local timer that's not mimicking the E7 times correctly, or the boost immersion heater (halfway up, on the 24h supply) has been left permanently switched on.

It's imperative to watch the meter and see exactly when it switches from normal to low rate (and vice versa) and to programme the Quantum accordingly..  Don't forget that some areas have a two hour interval at normal rate in the early hours so that also needs to be programmed in.

• What are the kWh costs and the daily charge?  If you are on an expensive tariff you will have expensive bills.
• Do a meter sanity check, if it's external make sure it's really your meter, not that of a neighbouring flat, and make sure the rates aren't transposed on the bill.

worlestone

Gerry1 said:

matelodave said:

They must have updated their instructions but not the FAQ's - apologies. I did have a look for them but obviously not hard enough.
Good info to give to the installer though if he is as useless as me 

No problem, the customer-friendly Dimplex instructions aren't easy to find !

This single supply facility should certainly be helpful for people replacing old NSHs, e.g. those on E10, THTC, White Meter etc.

Excuse my ignorance, I've been reading this thread to try and work out whether Quantum heaters would work for us.

We have E7 and older Dimplex NSHs, there is one electric supply coming into the house, the (new smart) meter shows both day and night rates which as far as I know switches the whole house electric @ 12:30 - 07:30 GMT (01:30 - 08:30 BST), but we have two separate RCD/Fused board things, one for sockets/lights/cooker/immersion/etc and another with the NSHs/immersion on. Does this mean we have a single mains supply or two as we have two separate fuse boards?

Asking as we are considering updating the heaters to give a boost in spring evenings, as it's been so cold lately, but it would mean additional wiring and the associated costs.

Thanks in advance

Gerry1

@worlestone If you have only an E7 meter (i.e. not THTC or some other legacy two-meter tariff) it will switch the whole output to the low rate overnight.  It won't know or care what the downstream circuit arrangements are.  It may have a 5th terminal that's only live at the low rate times, or it may operate an external contactor to do the same thing, but after the witching hour everything connected to that meter will be at the low rate.

Some modern meters have a Boost button that can be pressed to liven up the switched circuits for an hour, but this would be at the expensive daytime rate, and they are probably all smart meters.  It could avoid chilly evenings but the response times will be slower than with an inbuilt convector and if used frequently it rather defeats the point of having NSHs.

Modern NSHs such as Dimplex Quantum use a fan to release heat only when needed.  IF they are properly dimensioned AND correctly programmed they would not need to use the daytime supply for heating, although they have a convector for use if necessary.  They can also operate from only a 24h supply so the rewiring could be minor and not necessarily need extra cabling.  Unfortunately Quantums are not cheap, although they may (eventually) pay for themselves by reducing the heat lost overnight when it's not needed (and also during the day if you're usually out).