Scores of vulnerable and elderly residents were left without their Lifeline service at a sheltered housing block in Bexhill.
People at Thalia House in London Road said they also had no TV for several days and some housebound residents were forced to sit downstairs waiting to let people in due to the front door being broken.
Others said they had problems with their electricity supply.
Resident Lilian Piper, 80, said the problems started last Monday (November 12).
She said: “Having no Lifeline service was the most unacceptable thing. What would have happened if someone had had a fall? Around 100 people live here and many are housebound.
“One night everyone was kept up by the fire alarm going off throughout the night.”
An Optivo spokesman said: “We apologise to the residents at Thalia House following the recent loss of power in the building.
“The safety and wellbeing of our residents is of utmost importance to us and we have systems in place to respond quickly to issues like this.
“We were alerted as soon as the Lifeline system went down and we immediately prioritised dealing with the problem by contacting the provider.
“A representative from Lifeline attended the scheme that morning, checking all residents were OK and showing residents how to use their mobile phones to contact them in an emergency. The emergency pull cords in the individual homes were fixed that day.
“All of the power issues, including the fire alarm and door, were caused by a small kitchen appliance short circuiting all the electrics.
“Electrical contractors attended the site within hours to reconnect the power and deal with the individual issues.
“We are now undertaking a comprehensive review of the electrics at Thalia House to ensure a situation like this doesn’t reoccur. Once again, we apologise for the inconvenience this has caused to our residents.”
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