Lakesh Jakhu, 47, and his family are temporarily homeless after a blaze that left a workman needing hospital treatment for severe burns.
Mr Jakhu was sitting in the front room of his home in Pencombe Drive, Goldthorn Park, when he was shaken by the sound of the blast at 6.15pm yesterday.
The workman's van on the drive was engulfed in flames after, it is believed, a generator inside exploded. The van was destroyed and the house severely damaged.
"I ran outside and saw the flames," said Mr Jakhu.
"My first concern was for the workman - I wanted to make sure he was OK. I thought he was in the van.
"I put my hose on but there was so much fire and black smoke it did not make any difference.
"I then saw him run across the path and realised he was alive, but he was badly burned.
"I understand he was taken to the Queen Elizabeth Hospital in Birmingham."
Mr Jakhu made an emergency call and fire crews arrived to tackle the blaze, which took more than two hours to extinguish.
The workman, employed by IWJS on behalf of Severn Trent Water, had been working to clear a sewerage pipe of concrete running underneath the house.
Just an hour before the explosion Mr Jakhu had been celebrating his daughter's 17th birthday with his wife, Dipa, and two other daughters aged 21 and 7.
They had left to visit relatives and Mr Jakhu was in the house alone at the time of the explosion.
"They left about an hour before it happened," he said.
"I am relieved they were not here."
Mr Jakhu slept in his car outside the house while the property was made safe while his family stayed in a hotel.
The semi-detached house was badly damaged by the fire and the water used to put out the blaze. Black smoke has filled the rooms on the ground and first floors.
"Our family is devastated," said Mr Jakhu.
"We don't want to go back in there - it does not feel like our house."
This morning representatives from Severn Trent Water and IWJS visited the scene.
Mr Sarj Janagal, 33, who lives across the road, was at home when he heard the blast.
"I felt our home shake, there was a rumble," he said.
"A friend called and said 'what is going on in your street?'
"I went out into the yard and saw the van on fire just as the ambulance arrived. The house was ablaze - I could feel the heat from where I was standing.
"The fire brigade arrived and sealed off the area.
"It was very frightening."
A spokesman for West Midlands Ambulance Service said: "We were called to reports of fire on Pencombe Drive at 6.15pm on Monday. One ambulance, two paramedic officers and the West Midlands Care Team attended the scene.
"On arrival we discovered a van and house ablaze. We treated one patient, a man, for burn injuries before he was taken to Queen Elizabeth Hospital, Birmingham for further treatment."
A spokesperson for West Midlands Fire Service added: "At 6.16pm on Monday September 20, West Midlands Fire Service were called to reports of a house fire on Pencombe Drive, Wolverhampton.
"Initial crews arrived on scene within five minutes, with five fire engines with supporting vehicles and 25 officers in attendance at the height of the fire.
"This was a severe house fire which had spread from a van at the property and to the neighbouring house.
"Crews wore breathing apparatus and used hose reels to tackle the fire, along with main and covering jets.
"A gas pipe was damaged in the fire so as a precaution, the gas supply in the area was temporarily shut off to enable our crews to tackle the fire safely. The fire was put out by 8.30pm.
"All persons are accounted for and one man was taken to hospital by colleagues from West Midlands Ambulance Service having self-extricated from the property.
"The cause of the fire is believed to be accidental."
A spokesman for Severn Trent said: “We’re continuing to support the customer and a Severn Trent contractor, following a localised fire on Pencombe Drive yesterday evening.
"Our investigation to understand the cause of the fire remains ongoing.
"We’d like to thank West Midlands Fire Service for their assistance.”
A spokesperson for IWJS said: "We can confirm that a member of our team was taken to hospital following an incident in Pencombe Drive, Goldthorn Park, yesterday evening.
"A full investigation into the cause of the incident has been launched.
"Given the nature of our work, our priority is the health and safety of our people and the communities in which we work.
"We are currently liaising with the appropriate parties to establish the cause of this incident."