They made efforts to reduce their bills by switching off standby appliances and turning the thermostat down by one degree. But their bills continued to rise until a plumber visited and gave them some advice that saved them hundreds of pounds.
Writing in the Manchester Evening News, consumer writer Harriet Morphy-Morris shared the experience of her and her partner.
They are on a standard variable tariff with EDF and pay by direct debit, and up until recently, their bills were far beyond the average for the size of their household.
She explained: “It was only when we had to get a small leak repaired we realised we had left our immersion heater and consequently racked up a hefty bill.
“After seeing the immersion was on the plumber asked ‘if we had experienced any issues with our boiler’, I’m assuming he thought that could have caused the leak, after saying no and that our boiler was running fine we quickly realised our mistake. We had been throwing money away by using our immersion every day.”
Immersion heaters use electricity to heat the water for a property, even if a home has gas central heating.
Immersion heaters have been branded “insufficient” by experts at Which? because they use electricity constantly to heat water which is more expensive than gas.
In the couple’s rented home, they have a boiler and an immersion heater, and the latter can be turned on as a back up in case the boiler breaks or needs servicing.
They moved into their first house in early summer 2022, with their monthly bill increasing from £125 to £240, which was “a lot more than expected”.
They tried to bring down their bills by using their gas appliances as efficiently as possible, and submitting readings before the price cap rose in October.
This was when the Energy Price Guarantee was introduced, with average annual bills increasing to £2,500 a year.
Ms Morphy-Morris said: “When the October 2022 price cap came, at the same time as our EDF direct debit review (in this period customers are made aware of any credit on their account), we were defeated at the minimal credit amount on our account, less than £100, and continual £240 bill.
“It wasn’t until we had work done on a small water leak we realised that we had been ridiculously overspending by using our immersion heater.
“And by turning it off in October we have now accumulated £372 in bill credit – which is not surprising now that we understand how immersion heaters work and how much they cost to run.”
“By looking at the small amount of credit we had before October and comparing to now, we figured out (with the help of the EDF call handler) that the majority of the £372 credit was from reduced electricity usage.
“The amount of money we’ve saved since turning off the heater in October is a ‘calculated guess’ and a small proportion of the credit will be from overpaid direct debit payments.
The last substantial credit amount we were aware of was £172 between November 2021 and April 2022.”
A spokesperson for EDF explained what customers should do if they want a credit refund.
They said: “Anything over £150 at the end of their direct debit cycle is refunded back to the customer. If a customer wants a refund and has been billed up to date, they are welcome to request one.
“Direct debit monthly payments will be recalculated following this as the credit would usually be used to offset seasonal spikes.
“EDF was one of four suppliers to be assessed by Ofgem as having “no significant issues” with the way it manages its customers’ direct debit calculations earlier this year.
“This means our customers can be reassured that our Direct Debit process is robust. We’ll continue to work closely with Ofgem to make sure we’re following industry best practice for our customers.”