How to check if new storage heaters and washer cylinder installed correctly.

Scot_39

White Meter 1 according to the list of SP electrical heating tariffs - sounds pretty much like their old white meter 8-8.5 hr version of E7 - unlike some of the more complex 3 rate twin meter comfort tariffs etc.

https://www.scottishpower.co.uk/energy-efficiency/energy-efficiency-toolkit/electric-heating

Regarding the Quantum 150 - 1500W - its important when thinking about running costs to remember - that is only the nominal heat output - not the actual continuous - and in terms of electrical input - it's not the charge element rating (3.3 kW at 240V) - or the daytime boost element rating (1100W at 240V on the 150).

Some manuals also tabulate a max 2kW / 2000W output in the tables - e.g.

https://www.dimplex.co.uk/sites/g/files/emiian551/files/media_import/medias/docus/14/08_83324_0-3 QMRF Online G13 23-023.pdf

The 150 is the largest model and it charges at c3.3kW - at 240V nominal - and rated so can charge as much as 23.1 kWh at 240V - in the default E7 7 hour overnight window.  

The OP has whitemeter not E7 - so if discharging heat during the charge window - it can potentially take an even higher input charge.

In the Elnur equivalents - their shipped iirc with a target to take 80% of max on first charge before that charge adapted as needed if left in auto mode - not sure about the Quantums - but if similar - thats around 20kWh on the 150 model

20 kWh at SR c 26p  £5.20

The OPs night rates ?

Last time I saw SP WM rates was years ago - and not as steeply biased scales / balance vs others in south (off peak not as cheap).

Note therefore the heater is in theory capable of delivering more heat out than can be stored in a single charge - and has a boost heater in order to help it do so.

On models like Elnur - the boost heater can be triggered automatically - not sure about the quantums.

But for instance - if switched on in the middle of the day - without having had an overnight charge - the boost element would be the only source of heat.

And its important any boost modes then disabled / minimised as best possible - for the second day onwards

As the OPs 150 is dual wired - assuming one is meter controlled restricted - the Quantum manual says they auto detect when the restricted input is active - so in theory shouldn't have to set the charge times.

However their is also a boost heater - 1.1 kW - on the 150 - which could have been accidently triggered by the OP to charge at day rate - or left enabled by installer by accident - if heat actually required on the day of install. 

EssexHebridean

Could do with the OP returning and giving us some kWh figures rather than £ ones. That will rule out at least one possibility from the mix.