OSO water heater & energy bill help!

jamphss

Hi,
We have just moved in to a studio flat in Cardiff (2 of us), and are struggling to get our head around how to work the boiler/water heater.
Our first energy bill came through and it worked out about £120 for the month, which to me sounds far too expensive, so I am wondering whether we have the boiler set up wrong or inefficiently. One of us is working from home however are energy usage is relatively low with everything else (hardly ever have electric heating on, careful with lights etc..).
Our water heater is a "OSO Hotwater Direct 20 RD Unvented Water Heater", would really appreciate some advice from anyone on how to bring down the costs of running this while still being able to have hot water available for the evenings.

Thank you!! 

macman

Is your bill estimated or actual? £120pm tells us nothing, please can you post your actual kWh usage and the relevant dates?
What sort of electric heating do you have? You mention a boiler, but the picture shows a pressurised hot water tank-nothing to do wit the heating.
What tariff and supplier are you on?

Robin9

Is this supplying a conventional wet water system and radiators ?  If yes it looks like the most expensive way of heating your property known to man - it uses on peak electricity.

macman

OP refers to electric heaters, so probably this is for DHW only. It's a pressurised hot water tank, not an electric boiler.
Cheap convectors for the heating most likely, all on single rate.

Hasbeen

Well its not a BOILER its a modern version of a hot water cylinder that only heats hot water. Boilers are for central heating, and hot water.

It looks as though it has two immersion heater elements installed. Which one if any, is on all the time? Electric heating LOL   Are you on E7?

Google for instructions / E7 Tariffs /  Storage heaters etc. should have been left with hot water cylinder?

Someone with more expertise will be along to give advice 

Edit: As above.

Gerry1

If you have Economy 7, follow the cable from the upper immersion heater and make sure the outlet (possibly marked Boost) is left permanently switched off.  It's only there to give you half a tank of very expensive hot water from the 24h supply if you run out during the day, so think of it as Emergency Use Only.

The lower immersion heater outlet should be connected to the E7 switched supply and should be left permanently switched on.  At some stage, do a check that it's on the E7 switched supply by leaving it switched off until the water is cool, then switch it back on during the day.  You shouldn't get any hot water until the cheap rate kicks in around midnight.

However, if the room heaters are not Night Storage Heaters (i.e. they will warm up quickly at any time if switched on but go cold quickly when switched off) then you should be on a single rate tariff and start looking immediately for a new flat with gas, otherwise the setup will bankrupt you.

jamphss

macman said:

Is your bill estimated or actual? £120pm tells us nothing, please can you post your actual kWh usage and the relevant dates?
What sort of electric heating do you have? You mention a boiler, but the picture shows a pressurised hot water tank-nothing to do wit the heating.
What tariff and supplier are you on?

Hi, my meter reading was 66716 on 21/8/20 and then 67635 on 10/10/20 if that helps. 

Our heating appears to be just electric “radiators” with switches next to each of them, but we rarely use these!
tariff is “standard SC electricity DD” with npower 

jamphss

Both cables from the upper & lower immersion heaters go into this box if that helps  

Gerry1

jamphss said:

macman said:

Is your bill estimated or actual? £120pm tells us nothing, please can you post your actual kWh usage and the relevant dates?
What sort of electric heating do you have? You mention a boiler, but the picture shows a pressurised hot water tank-nothing to do wit the heating.
What tariff and supplier are you on?

tariff is “standard SC electricity DD” with npower 

AAAAaaaarrrggghhh !

You're on a cripplingly expensive standard tariff.  You can check your rates here.   In my area your tariff would be 17.6631p/kWh plus a daily charge of 24.5007p.  I'm paying 12.11343p per kWh plus a Daily Charge of 13.2825p, so you can see how you're being ripped off.

You'll need to switch to a competitive tariff PDQ.  Whatever you do, it's still going to be expensive if you don't have gas.  It'll be expensive if you have storage heaters, cripplingly expensive if you don't and bankrupcy inducing if you're running non-storage heaters on an E7 tariff.  Not what you want to hear, but there's no gentler way of putting it I'm afraid, that's the reality of being all electric.

The first thing you need to do is to find out whether you have storage heaters and, as previously asked, are you on single rate or Economy 7?

The box on the wall allows your main immersion heater to shadow the cheap rate times of an E7 tariff if you have a cheapskate installation that has only a 24h circuit rather than a switched E7 supply and a 24h circuit for emergency top ups.  If you're on an E7 tariff it's very important to make sure the box is accurately programmed to mimic your meter's cheap rate times.  The main switch would be left permanently on and the boost should only be used for an emergency top up of half a tank of hot water if you've messed up and run out of hot water during the day.

 Over to you to do your homework and report back !

Gerry1

jamphss said:

macman said:

Is your bill estimated or actual? £120pm tells us nothing, please can you post your actual kWh usage and the relevant dates?
What sort of electric heating do you have? You mention a boiler, but the picture shows a pressurised hot water tank-nothing to do wit the heating.
What tariff and supplier are you on?

Hi, my meter reading was 66716 on 21/8/20 and then 67635 on 10/10/20 if that helps.

Pro rata that would be 6709kWh per year, but obviously you're likely to use a fair bit more when it's cold and dark.  Perhaps make a guess at 10,000kWh?  You haven't given any other figures so that suggests you're on single rate and have non-storage heaters.  So 'cripplingly expensive' but not quite 'bankruptcy inducing'.

When you've confirmed the facts, start comparing using Citizens Advice and 'Switch with Which?'.  Ignore all claimed savings, just compare annual costs (not the DD amount) based on your guesstimate of annual consumption in kWh.

If you don't have E7 and don't need it, you could set the wall timer to give you perhaps an hour or two before you get up, and then give it a quick boost in the evening if necessary.  That will reduce the losses during the day; every little helps.

macman

Can you post a pic of your meter please?