Just wondered if anyone has experience of running an ASHP using the cheaper rate economy 7 tariff and whether it makes any real difference in running costs. I seem to remember that you have to pay a slightly higher day rate if you have E7, and that, coupled with the fact that the ASHP would be running at night when it might be cheaper but also colder would seem to maybe cancel any financial benefit. Also, it seems that running an ASHP 24/7 makes better sense and it's unlikely to be able to run an ASHP on normal rate during the day and E7 at night.
Thanks in advance to anyone who can shed some light on my ignorance!