What a correctly commissioned MVHR system actually costs to run.
Primary question · Once the install is paid for, what should I realistically expect to pay each year to keep MVHR running properly?
A well-commissioned MVHR unit draws between thirty and seventy watts in normal occupied operation, which works out at roughly £60 to £140 a year in electricity at current price-cap rates. Add a set of filters every six to twelve months and the realistic operating budget for most British 3-beds sits between £90 and £180 a year. The heat recovery offsets a meaningful slice of this in winter, though not enough to justify the install on its own.
Anyone trying to forecast the real running cost rather than the marketing one.
Electricity: £60 to £140 a year. Filters: £30 to £80 a year. Annual half-day clean: do-it-yourself or roughly £120 if outsourced.
- The fans are genuinely low-power on a sensible unit
- Filter changes are simple and the unit tells you when they are due
- Heat recovery offsets a useful slice of the winter bill
- Skipping filter changes for two years can double the electricity draw
- A poorly commissioned unit runs harder for the same result
Diary the filter change at the six-month mark for the first year, so you discover early whether your household needs it sooner.
MVHR rewards households that diary the maintenance. The unit that gets a set of filters in November and a vacuum of the core every spring quietly disappears into the background. The one that does not slowly turns into a fan running at the wrong speed for years.