A New Plymouth factory's furnace fire proved a little too hot to handle and sent smoke billowing out of the building this morning.
Firefighters were called out to Cambrian Engineering on Carrington St just before 7am.
Senior station officer Ian Drewery said firefighters went into the factory with breathing apparatus and used a thermal imaging camera to find the source of the smoke.
''They have a furnace for hardening steel and the heating is electronically controlled. There was a malfunction in the electronics and it got too hot and the salts in it caught fire.''
Firefighters tried to use dry powder to put out the fire, but also used water to lower the temperature of the furnace.
''It's contained and stable but it's 600kg of molten salts so it's going to take a while to cool down. We left it in the hands of the company.''
Mr Drewery said the firefighters had also taken out some windows in the factory to help vent the smoke.
Cambrian Engineering did not want to comment.
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