A fire that forced a Blenheim couple to flee their home was started by a fault inside a heat pump, a fire investigator says.
Fire Service Marlborough fire safety officer Lewis Jones, who investigated the blaze, said he suspected there had been a malfunction in the heat pump’s internal fan motor, which caused it to overheat and catch fire.
The fan was on, which helped spread flames quickly, Mr Jones said.
“As opposed to smouldering, it got involved reasonably quickly into a full-blown fire in the unit.”
The fire spread through ducting into the wall, he said.
Meryl and Peter Pentchev were woken by a smoke alarm early on Friday morning and saw flames coming from the heat pump in the living room of their Weld St house.
Mr Jones said fires started by heat pumps were unusual, but not uncommon.
The heat pump was about 10 years old, but there was no history of how the machine was maintained before the Pentchevs bought the home in September.
“What has caused the malfunction will remain a mystery,” he said.
“It’s like any engine. A bearing can get tight or it can get choked up with dust and cause resistance and make them work harder.
“People can still be confident that heat pumps are a good unit, but it proves that they have to be maintained and serviced.”
Three independent electrical experts helped with the investigation, Mr Jones said.
Cuddon refrigeration and airconditioning manager Neville Patchett said he was surprised at the findings.
Mr Patchett did not recall any major problems with heat pumps in 20 years, and incidents like the Pentchevs were rare, he said. As long as people kept filters clean and rubbish clear of the outdoor unit, there was no reason for problems, he said.
Cleaning filters enabled better air flow and improved efficiency, he said. If people looked after their heat pump, it should not need servicing.
TIPS FOR LOOKING AFTER A HEAT PUMP
Clean your heat-pump filters twice a year.
Filters can be found by opening the front panel of the unit.
Keep rubbish away from the outdoor unit of the heat pump.
Heat pumps can be serviced, but this needs to be done by a professional.
Units usually need to be serviced only when there is a problem.
REFERENCE: http://www.stuff.co.nz/marlborough-express/news/3848905/Warning-Keep-heat-pumps-clean