Isolation transforners

[jam19895]

When I am plugged into shore power using line "A", one of my two isolation transformers in the port transom locker has a soft buzz. Recently I had the opportunity to plug in both 30 amp lines to shore power (my marina only offers one 30 amp plug), and an extremely loud buzz persisted from one of the transformers, obviously the one for line "B". I spoke to a representative of the company who makes the transformers and she said they should not buzz. Fortunately, the company replaced them under warranty sans labor. Most unfortunately, the Hunter service department in my area states that it will take 2 men approximately 4 hours to replace the transformers for a total of $480. I have found limited information on transformers, their diagrams, and installation. I also have discovered that some Hunter 36 owners have only one transformer, while I have two. Why? In the Hunter boat reviews I did find comments about transformers buzzing and subsequent replacement of those transformers.Has anyone else experienced similiar problems with the isolation transformers? I would appreciate any information on this issue. Thanks!

 

[Randy Conkling]

Buzzing transformer

I have a 2004 306. Shortly after taking delivery of the boat, the transformer started buzzing very loudly. You could hear it on the dock 3 slips down. Forget trying to sleep in the aft cabin. If you unplugged shore power for a few minutes and then plugged it back in, the buzzing was almost gone. Within a few seconds, the buzzing would return and build back to the loud level within minuets.Hunter sent a replacement transformer and paid for the installation labor. The boat was only a few months old when this occurred. I believe that the transformers are very heavy and difficult to handle during installation. This is why you were quoted the high labor charge. The mechanic that installed mine complained about his aching back for a week afterward.The new transformer still hums, but you can only hear it if you stick your head into the locker.