ashp running costs

aleary5a

i have a grant aerona ashp fitted to a 4 bedroom bungalow built approx 3 years ago electric bill for last quarter was approx £1000 does this seem excessive anyone got any tips on how to reduce my electric bills

Cardew

Welcome to the forum.


Is the £1,000 bill based on actual meter readings and not estimated meter readings?


Of course £1,000 is excessive, it would be excessive if you heated the house with straight electrical heating; especially in a 3 year old property which must have high insulation standards.


However you need to post more details of the system and how you use it - under-floor heating? Radiators? temperature of water? Retrofit or installed from new? etc


The normal cause of high electricity consumption with an ASHP is an immersion heater in a thermal store operating for long periods. Although in a mild winter, nothing should come close to £1,000.


There are a few experts on heat pumps who visit this area and they will be able to advise.

[Deleted User]

aleary5a wrote: »

i have a grant aerona ashp fitted to a 4 bedroom bungalow built approx 3 years ago electric bill for last quarter was approx £1000 does this seem excessive anyone got any tips on how to reduce my electric bills

Our EcoDan munches through about £650 per anum. 100+ year old house in rural Scotland.

matelodave

Dunno what our 11kw Daikin uses on it's own, but despite my wife's best efforts with the washing, drying, cooking, cleaning, lighting, TV & computers etc we used less than 8000kwh last year in our 1986 three bedroomed detached bungalow. We are at home all day as well so the heating is running nearly all the time. Our total electricity bill was just over £800 last year on a single rate fixed tariff (ie not E7)


So you've got something seriously wrong if you are using all that energy. Either it needs the settings checked or there's a fault somewhere. Did you use this amount of energy last year? What tariff are you on E7 or standard? Has anyone been tweaking the controls? Do you use a backup heater to heat the water, if so, it's possible if you are on E7 that the timer on the heating system is out of sync with your low rate.


Ignoring the cost, what is your weekly energy consumption in kwh and how does it compare with last year, bearing in mind that this winter has been a lot warmer than last years so you should be using a lot less (we used 1500kwh in Jan 2013 but only 905 in Jan 2014).
The only way you are going to see what's going on is to read your meter very frequently to see when all the power is being used.

aleary5a

my electric is economy 10, hot water temp is between 35 and 45, ufh is in all rooms, there is a electric hot water boost on water tank this was set to come on for an hour every day could this have caused my high bill, i have now set it to come on at weekends only for one hour it was fitted to a new build house by mcs registered installer, four bedroom bungalow 160 sqm two people living in it

lovesgshp

Are you talking about your UHF heating temp or DHW @ 35-45? Please forgive me, as I am not up on Economy 10 heating, but I presume you only have 10 hours at a cheap rate.
What temperature have you got the rooms set at?

aleary5a

that is the temp on the control panel inside the house, most rooms are set at 18 none are higher than 20, i have multi fuel stove in living room that is on most evenings and weekends, i assume you are correct on the e 10 rate

lovesgshp

Thanks. 18-20 House temp looks perfectly okay for UHF. What temp is the DHW set at?
If you have a multifuel stove that is on most evenings, then that should reduce the running hours on the pump.
I do not know the Grant unit, but has it a section on the menu where you can look at the running hours of the heat pump?

lovesgshp

Just had a look at the E10 rates. It looks like you can have 3 hrs in the afternoon, 2 in the evening and 5 overnight. Are you operating it on a 24/7 basis, or timed for the cheaper cost only?

matelodave

I'm on a standard tariff £0.1105p a kwh with a standing charge of £0.221 per day. How does that compare with your E10 tariff. I'm not convinced that an E10 or E7 tariff is suitable for a heating system that's running virtually all day. What size is your heat-pump, if it's undersized then it will be running all the time.


Try reading your meter daily for a few weeks to see what's happening. Our bungalow is 140 sq.m so not much smaller than yours, built in 1986, 300mm loft insulation, cavity insulation of an unknown quality, double glazing fitted in 1999 and no underfloor insulation. I'd expect that you should be using significantly less than us and certainly less than £1000 a year

aleary5a

the heat pump is switched on 24/7 at first i had it set to come on at the cheap rate but was advised against this as the unit is designed to be switched on all the time, i have had the installers and the manufactuers check that the heat pump is sized correctly and they assure me that it is, there is no section to check the running hours on the control panel it is a 13kw output