taken our H reg 813 cargo horse box for test all ok , but when dumping the air the tanks would not refill in time, got home and did the same again tank filled up as normal repeated many times and all ok. Got up next day and again air will not build up quickly. left for 20mins and tryed again all ok. Please help as need to retest Thanks

Jase, August 2009

They used to suffer with blockages in the steel pipe from the compressor to the air drier. the pipe gets blocked with carbon on the inside. if left to tick over,t he air pressure eventually builds up. hope this helps, in my experience the only cure is to replace the pipe.

paul, August 2009