[Amps] Water cooled amp question

[Joe Subich, K4IK]

Donii at sympatico.ca writes: 
> 
> When the transmitter was turhed off a simple $5 110v 
> automotive engine block heater would have kept things 
> from freezing.

Not in that transmitter ... the cooling system contained 
about 100 gallons each.  The transmitter was in an unheated 
building, the reservoirs were stainless steel and uninsulated, 
the pipes were uninsulated copper and the heat exchangers had 
several thousand square feed of effective area.  

At zero degrees Fahrenheit or below, the block heater would 
have needed to be several KW and auxiliary pumps would have 
been needed to move the warmed water through the exchangers 
to keep them from freezing.

It isn't an issue these days since most commercial stations 
never sign off but 15 or 20 years ago, a lot of stations 
went dark between midnight or 2 AM and 6 AM local.  

73, 

   ... Joe, K4IK