The New Zealand Professional Firefighters' Union has blacklisted yet another truck saying it's a safety risk to its members.

The Christchurch City Fire Station's main truck is the second firefighters are refusing to use.

Northern branch secretary and spokesman Boyd Raines says the issues are generic and affect New Zealand's entire fleet.

He said the risk to firefighters and the public is too great.

He said the trucks have failed to pump water, door handles have fallen off and gears have stuck.

"When a truck fails to start when it's called to a fire that's pretty serious. It's not the first time. This truck and other trucks of the same make have failed in this way."

The Union claimed there have been 215 faults in the more than a dozen engines operating across the country, since they were introduced 18 months ago.

After the blacklist of the Auckland vehicle, Raines said it's only a matter of time before a truck fails on a job and somebody gets killed - whether it's a firefighter, or a member of the public.

Meanwhile, the Fire Service is rejecting claims about Auckland City's main truck - the first to be blacklisted, which was taken away for repairs on Friday.

Assistant National Commander of the New Zealand Fire Service, Kerry Gregory, doesn't share the concerns.

"I've got no concerns for the safety of the public or our firefighters - if I did I'd be taking them off.

"I would have no hesitation in removing any appliance myself, if I felt there was a genuine safety concern."