Replacing an old Economy 7 heater with a modern one, will I save much on electric bills?

RedFraggle

Modern storage heaters like Dimplex Quantum only take the energy they need. Some nights they don't charge at all. You wouldn't need to manipulate the charge time just get them set up correct and don't use any secondary heat source. When it was really cold mine still had heat in them at 10pm. 

Dandytf

RedFraggle said:

Modern storage heaters like Dimplex Quantum only take the energy they need. Some nights they don't charge at all. You wouldn't need to manipulate the charge time just get them set up correct and don't use any secondary heat source. When it was really cold mine still had heat in them at 10pm. 

Due to be installed tomorrow, I'm reding info that 2 circuit install is preferred.
Not sure if I want to switch from SP eco 7 (White Meter) tariffs depending on how DQ is installed.
I'm expecting surge for initial overnight heating, hopefully settling down consumption+energy cost wise over this week.
Have slightly raised DD to cover SP SVR rates post 2 yr fix.
I hope nearer winter to programme maybe 2 hrs pre 8 a.m. heat then 2 hrs 17:00-19:00 to start with.
Though if Electrician demands Single circuit install I could consider making switch to another supplier-not my preferred option by any means.

thanks

Stubod

...all our NSH are single supply, and I don't want / need to change them all. Ours are normally "fully off" between April and October, ('ish). Ideally I probably need to change 2, the living room and the hall, bith of which I can probably run a spur to get the dual supply. Every supplier I have spoken to has told me I need 2 supplies. At least that way the "main heating power" will only be on during the normal economy 7 time period..

Gerry1

Dandytf said:

RedFraggle said:

Modern storage heaters like Dimplex Quantum only take the energy they need. Some nights they don't charge at all. You wouldn't need to manipulate the charge time just get them set up correct and don't use any secondary heat source. When it was really cold mine still had heat in them at 10pm. 

Though if Electrician demands Single circuit install I could consider making switch to another supplier-not my preferred option by any means.

thanks

The electrician should do what the customer wants.  However, it may mean lifting floorboards etc, so perhaps that's not in his skill set.

Two circuits are better because you can't end up charging at day rate if there is a variance between the actual E7 times set by the meter and the cheap rate times programmed into the Quantum.  The E7 times could change or there could be GMT/BST issues so it gets rid of the risk.

However, you still need to ensure that the expensive daytime boost isn't set to come on automatically without your knowledge.  That could make your bills rocket, undoing all your good work.

If you do end up with a single circuit, take great care to check all the programming yourself.  Don't rely on the electrician because he won't be around at midnight to check the switchover takes place at the right time.  Make sure one switched circuit outlet has a neon indicator so you can see at a glance when the cheap rate is in operation.

But why are you thinking of changing supplier if it's a single circuit?  You should be using the same amount of energy at the same times so it won't make any difference.

markin

Gerry1 said:

markin said:

Heat pumps have a cop of 3 to 5 that means 1kwh of energy in is 3 to 5kwh of heat out

Those figures seem a bit optimistic, especially for an ASHP.  Even a GSHP might struggle to reach COP5 consistently.

This panasonic air to water SCOP 5.12
https://www.aircon.panasonic.eu/GB_en/happening/aquarea-k-l-series/


Air to air models

NZ series 

Heating capacity 6.5 kW
Efficiency SCOP 5.00
Energy efficiency class for heating A++

FZ super-compact • R32   ,  2.5 kW model  COP 4, Scop 4.2

https://aircon.panasonic.eu/GB_en/product/fz-super-compact-r32/

Dandytf

@Gerry1


Whilst 2 Circuit Install remains no 1 priority, I'm not sure how much control I have over this preference.
I only mention possible Supp switch as I thought there are potential better Single Rate Tariffs from SP competitor's .
That 2 Circuit Floorboard comment, is that what could be required say if a new Circuit has to be added, I see my current Eco 7 Circuit +Standard Circuit may not be enough as I'll need 'Dedicated 24/7 Live Circuit'

Hopefully find way forward today.
Dimplex Hub 'Control App' downloaded.

thanks mser's this is my most important home improvement during '23 and completes what's been achievable which is nice. 

Dandytf

Gerry1 said:

Dandytf said:

RedFraggle said:

Modern storage heaters like Dimplex Quantum only take the energy they need. Some nights they don't charge at all. You wouldn't need to manipulate the charge time just get them set up correct and don't use any secondary heat source. When it was really cold mine still had heat in them at 10pm. 

Though if Electrician demands Single circuit install I could consider making switch to another supplier-not my preferred option by any means.

thanks

If you do end up with a single circuit, take great care to check all the programming yourself.  Don't rely on the electrician because he won't be around at midnight to check the switchover takes place at the right time.  Make sure one switched circuit outlet has a neon indicator so you can see at a glance when the cheap rate is in operation.

But why are you thinking of changing supplier if it's a single circuit?  You should be using the same amount of energy at the same times so it won't make any difference.

Haven't got times in front of me though easily downloadable, almost certain Eco7 aka White Meter is from t.b.c. could be from 22:00-08:30 re check tonight.
Smart Meter has incredible Digital Countdown Bars via IHD with Scrolling Text ahead of rates switch each night and next morning.

Due to change from Low rate to Day Peak rate- 60 mins from 07:30.-08:30

thanks

Gerry1

Don't even think of a Single Rate tariff if you have storage heaters.  By definition  they're only cost effective if charged up on a (relatively) cheap overnight tariff.

The only exception might be during the summer months when the NSHs are switched off: single rate might then be slightly cheaper if you don't use much hot water, but you'd have to remember to switch back to E7 in the autumn.

RedFraggle

Set the Dimplex to charge for your off peak period but don't reduce it down manually. It'll work out when to stop charging itself based on your demand for heat. Unlike the old NSHs it won't charge for the whole period to a fixed temperature it'll take the charge needed to supply you with the heat demand of your heating programme. 
They take a few days to get it right so don't let the first few days charging panic you. 

Mine are off now but across winter I had my 2 1200 quantums set to maintain 21C from 7am to 10pm and this is the charge taken

Stubod

I have heard the the Dimplex Quantums are "difficult/complicated" to set up. Just wondering what users experiences are and whether they are worth the extra over the more conventional types. I would certainly like to get at least one new heater installed before next Winter?