Electric heater comparison

danrv

matelodave said:

If you went for E7 then there's no doubt that your timings would be reset and you would only get off peak energy between midnight and 7am so you be using your convectors on peak rate energy - unless you are a night owl and only heat the place overnight. 

Thanks. Yes, thought so. 
Midnight - 7.00am at around 9p a unit would be an improvement on nearly 13p a unit off peak at the moment.
Whether that will balance out the direct heating at 17-18p per unit on E7 against 7 hours off peak use during the day at 20.408p (current E10), remains to be seen.

coffeehound

matelodave said:

If you went for E7 then there's no doubt that your timings would be reset and you would only get off peak energy between midnight and 7am 

There were a couple of examples on here where people on E10 transferred to E7 and -- as far as could be seen from their posts -- allowed to retain their E10 off-peak hours.  i.e. the supplier just swapped tariffs without any adjustments on site.  

Whether that is an unofficial policy to avoid households being left without enough stored capacity, perhaps only extended to vulnerable customers, who knows.  It would be very useful to know for sure.  Perhaps danrv you could ask some questions of your supplier before deciding.  E10 hours at E7 prices would be a good situation.

danrv

coffeehound said:

 Perhaps danrv you could ask some questions of your supplier before deciding.  E10 hours at E7 prices would be a good situation.

Thanks. Yes, would be good especially as mine are approx. 5.10am to 3.10pm.
Eon have said they can quote for a switch to single rate but for the best deal on E7 or other, it wouldn’t be with Eon.
Maybe would have to be for any chance of keeping the times.

As far as I know, the mechanical timer is the original from the 70’s and was last reset Feb ‘98 according to the sticker.
Looks like a digital Multirate meter was installed in Feb ‘08.
I take it that any changes made here would be down to the new supplier if I switched. But then what happens to the times?
I thought anyway that they are set by the DNO.

coffeehound

@danrv it would be worth just asking the question.  If you were to say that your installed C/H is an off-peak warm air system that is too expensive to run on E10, but won't have sufficient stored capacity to use E7 hours, and that you can't afford a new Lot-20-compliant install, there might be room for discretion there, who knows.

danrv

coffeehound said:

@danrv it would be worth just asking the question.  If you were to say that your installed C/H is an off-peak warm air system that is too expensive to run on E10, but won't have sufficient stored capacity to use E7 hours, and that you can't afford a new Lot-20-compliant install, there might be room for discretion there, who knows.

Thanks. Yes, maybe. 
I would be happy to try the warm air system on a 7 hour charge to see how it goes.
It was mentioned before and does still kick out heat even though the exterior is cold. While there’s the ‘why fix it if it ain’t broke’ view, the main problem is not being able to clean or the cupboard it’s in. 

I’d overhaul it and the ducting too if it wasn’t for the possibility of containing hazardous materials. It’s caused cracks in the walls through decades of warming and cooling and is a sort of no go area. 
Trying to do my best to find an alternative. 
Not sure what the new Lot 20 compliant install refers to (Quantum NSH’s maybe) but budget under 6k is not really a problem.
I’ve ruled out fitting these throughout due to the rewire and wall chasing required. Could manage a couple maybe in rooms nearer the CU.

Might seem like I’m not getting anywhere with the heating situation but turning off the warm air heater and trying cheap convectors I hope is a step in the right direction. 
The ability to redecorate the house interior prior to fitting any heating is important. I don’t mind then if the system adds value as long as it’s cheaper to run and modern.

coffeehound

I think you said previously that the warm air system stores 10 kWh?  It's doubtful that would keep the house warm for 17 hours between charges.  By suggesting that Quantums would be too costly, you maximise your chance of a sympathetic response, if you see what I mean.

danrv

coffeehound said:

I think you said previously that the warm air system stores 10 kWh?  It's doubtful that would keep the house warm for 17 hours between charges.  By suggesting that Quantums would be too costly, you maximise your chance of a sympathetic response, if you see what I mean.

The Unidare heater stores up to 73 kWh. 10kw input rating.
I see what you mean now. Referring to what to ask and simplifying it.

danrv

matelodave said:

If thats your plan then just dont look at costs - you need to know how much you use in kwh, not £££'s.

Read your meters at least twice a day for a few weeks, before you go to bed when most stuff is off and in the morning before you start turning stiff on, so you can get a view of you day/night consumption especially if you've still got your hot water on off-peak. Its the only way you can determine whether a single rate tariff will work for you.

 However  don't be surprised if your electricity bill sky rockets whilst you are using "on-demand" heating on an off peak tariff because peak rates ae generally around twice the cost of the off-peak one although you do have the flexibilty of only heating one room at a time.

During the cold spell, I’m using an average of 40kwh a day. Sometimes up to 43kwh.
With the E10 times at 5.10am to 3.10pm, there’s a little more off peak use than peak.
A recent day reading was:
22 kWh off peak at 12.969p a unit = £2.85
18 kWh peak at 20.408 a unit = £3.67
Total £6.52.

If I keep using the convectors, I’d need a very good single rate deal (14p or less) to make a decent saving on electricity bills.
Probably no point in switching to E7 and not use storage heaters. A couple of Quantum QM125’s (2760w input) and a QM100 (1650w input) on E7 off peak rate of 8.937p hopefully will be cheaper heating for main living spaces.

danrv

matelodave said:

Bear in mind though that it could still be radiating heat during the charging period so ideally the damper should be closed right down during the charge period to achieve it's maximum storage capacity. 

Yes, that heat leakage can be beneficial even though it’s a downside to storage heaters in general.
Don’t necessarily need heat between 12.00 -7.00am so if a Quantum retains it much better than standard NSH’s, they should be a bit cheaper to run. 

matelodave

High heat retention storage heaters
The most efficient modern storage heaters are called ‘high heat retention storage heaters’, and are up to 27% cheaper to run than standard storage heaters. In addition to the features of other modern storage heaters, these models achieve even better heat retention and are able to estimate the next day’s heating demand based on user heating habits and climatic conditions (meaning you do not need to worry about adjusting input settings). High heat retention models include Quantum heaters (from Dimplex/Creda and Heatstore), Elnur (Gabarron) Ecombi HHR heaters and the Stiebel Eltron SHS and SHF range.

Replacing old storage heaters with high heat retention models may also improve the Energy Performance Certificate (EPC) rating for the property

It seems that Quantum have become the defacto name for HHR heaters in much the same way as people called vacuum cleaners "Hoover's"