Mr Stewart claims his boiler failed at the beginning of August and he called Scottish Gas to investigate.

When an engineer came out, he ruled that the boiler was beyond service and hung a sign on it warning that it should not be used.

The Stewarts thought they were in line for a new boiler fairly quickly due to a free repair or replacement offer by Scottish Gas.

However, when they called up to follow up on the progress of their claim, they were allegedly told that Scottish Gas was “awaiting parts”. The confused family explained that their boiler had been condemned as they were told parts could no longer be secured for that model.

They were allegedly told there were still parts available but that they were rare. The delay in fixing the boiler was said to be down to the difficulty in securing these.

However, as Dundee plunges deeper into winter, the family’s situation is becoming more desperate, and they’ve been forced to move into a single room.

Mr Stewart said, “I’ve had to move my bed into the living room and our youngest girl Stevie (age two) has been sleeping in with us.

“The other kids, Alex (20) and Michael (13), have also taken to sleeping in the living-room as it’s the only place we can get heat.

“I’ve got heart trouble and I’m on Warfarin, which thins the blood and makes it hard for me to keep a heat.

“It’s also murder for little Stevie who is prone to the cold.

“We used to have our grandson living with us as well but he’s had to move to his other grandparents’ house because its so cold in here.

“It’s got to the point where I actually look forward to getting up and going to work in the morning as it’s the only place I can get warm.”

A spokesperson for Scottish Gas said the complaint was now being investigated.

She added, “Scottish Gas regrets if there has been a problem with a customer care service and we are doing everything we can to resolve the situation as soon as we can.”