HELP!!
I have spent a month trying to get a direct answer to a fairly simple question. Here is the question:

Which of the following three heaters is the most quiet:
Qmark (CWH Series)
Berko (FRA Series)
King (LPW Series)?

I have contacted the manufacturers, retail outlets, and distributors.
I have tried five other forums.
I have gone into retail stores and contractor shops to listen to any one of the heaters and have been told that they can't hook them up.

As yet I have not received a definitive answer to my question.
I can't even get information on how quiet (or noisy) any one of these heaters is.

If there is anyone out there who can help me please reply.

Thanks.
artmann