Storage Heaters: Quantum or Duo

radiant

My two bedroom flat was built in the early 1990s has Econ 7 electric supply and the original Dimplex storage heaters (one CXL unit in the living room, XL in the hallway and bedroom and a panel heater in the other bedroom).

My plan is ultimately to replace all the storage heaters and have panel heaters in both bedrooms, but initially I'm tackling the living room. The existing heater does not have adequate output to keep the room warm so I'm going to add an additional storage heater and possibly replace the exiting unit (if funds allow). I don't want to be dependent on any fans or boosts at any time and most of the heat I'll be using will be in the evenings.

For the choice of storage heaters I'm guessing it's between the Dimplex Duo and Quantum ranges. I don't have any long term plans for integrated heating control between rooms; I just want whatever is in the room to its job as effectively as possible. I've been told that the running costs of the Quantums will recoup the price difference over Duos within a few years. I like the idea of the Duos though as they seem simpler to operate and I'm not sure I need all the extra stuff the Quantums offer. So, I'd be grateful if anyone could answer the following:

1) are Quantums more efficient at storing heat than the Duos? Given I only want to use stored heat, this could be a big plus?
2) is running the Duo as an uno (i.e only stored heat) possible or sensible for this unit?

I'd also like to confirm the size of heaters I would need. My living room measures (in feet) approx 19 x 12 and 7.7 in height which I reckon requires 3.6 kW to heat, so I should aim to get the largest output unit of whatever range I go for (i.e. 1.5kW for Quantum or 1.4kW for Duo)?

Many thanks.

Richie-from-the-Boro

If you intend room heating without a central all-house control then the cheaper DUO will be just as good. As far as I'm aware the DUO and Quantum both have nano-blanket type insulation quantifiably better than the older types such as rockwool or ceramic types in use. You can simply change like for like at any point in time each individual storage heater, its just 3 wires out and the same 3 wires in. Room size :

Storage of the cheap stuff is the trick, the DUO will store marginally less kWh total output than the old school cans, for example if you had a 3.4kW heater in your living area that was not holding enough then you would need more cheap stored heat to begin with, two heaters are better than one if you have the real estate - what size is the one currently in your living room ?. Read this one of hundreds of threads and get back with questions. Best of luck.

radiant

Thanks for the reply - I'll have a read at the thread (I did read quite a few but missed that one).

The Dimplex dealer I spoke to didn't even mention the Duo range; he just quoted either an XLS18 or Quantum 070 as suitable additional units. When I enquired about Duo he stated they weren't as cost effective as a Quantum.

I think it's a CXL24 model I currently have (going by its dimensions) which is 3.4kW. However, it's located close to the living room door and at the opposite side of where the windows are - it's this area that needs some additional heat. My neighbour directly one floor below me (i.e. same living room layout) replaced his CXL unit with a Quantum and it hasn't addressed the problem of heating the entire room.

Richie-from-the-Boro

2 is better than one and radient is better than convected and line of sight is better than none line of sight. Both DUO and Quantum if used correctly will in addition to the existing 20a wiring need a 13a switch close to the new heater. Stored quantity is not really complex. If 3.4 was inadequate an extra small DUO in the same room will bank an extra 25% of the cheap stored stuff and stop the DUO or Quantum switching on its 13a full price day-rate spplementary panel element.

Having the panel element available, even if you never intend to make everyday use of it is an excellent insurance against any eventuality. Two half kW front on demand radient heaters will bump even a sub arctic cold spell back into the comfort zone very quickly.

The bedroom and bathroom panel in today's energy cost spiral is a workable and flexible on demand alternative, and any good e-stat and timer will do that so you could buy a non Dimplex but the quality of the e-stat would in my opinion be critical. I'm out till later tonight but there are many competant people here who will jump in and help. Best of luck,

1+2 cyanogen

radiant

Thanks again - really appreciate the help!

One last question on the Duo. Having had a quick look at the controls manual it seems there are two user controls: Background (storage) and Comfort (panel). How would you be able to limit the amount of stored heat released during the day with this system i.e. if I wanted to store as much heat overnight as possible but not release the bulk of it until I get home in the evening? I'm quite happy to have a cool living room during the day then have more heat in the evening.