People living in 11 blocks of flats around Exeter Place, just off Wellingborough Road, had work carried out on their communal entrances to improve security. Existing gates were replaced by Northampton Partnership Homes workmen with opaque doors
But it unfortunately means daylight cannot activate sensors behind the doors, which are connected to the communal lights.
There the flatblocks' lighting system believes it has been dark since February 4 and has left the hallways and stairwells illuminated for 17 days straight.
Residents association co-chair Dee O'Neill said: "We pay the bill for communal areas, split between us.
"Who's going to foot the cost for all this? It will be the tenants."
In Dee's case she will have to pay a comparatively large percentage of the forthcoming charge because, as a leaseholder, it is worked out by the size of the bedrooms in her flat. With two double bedrooms, she fears an inflated bill for four people.
A public meeting was held about the issue on Wednesday as tenants feel their protestations are falling on deaf ears.
Michael Spittles said: "We have tried to speak with the overseer of Exeter Place and Portland Place complex, but he just ignores us, he doesn't listen."
A spokesman for Northampton Partnership Homes said: "This has happened after an upgrade of security,
"The photo cell that recognises whether it is light or dark is shielded by the new doors.
"Unfortunately, we can't switch the lights off on stairwells and corridors for safety reasons."
The spokesman did say that NHP was working on a solution, and an upgrade of all the communal lights to a low-energy system.