[VACList] electrical question

["Dick Parins" <2867@xxxxxxxx>]

The installation instructions for my new water heater are very specific 
that if used with a converter there must be a battery in line and the 
converter power must be "filtered (pure DC)".  The instructions say to test 
the circuit by using a multimeter set on the AC voltage scale.  It says "If 
the reading is more than 1/2 volt, the circuit is not DC voltage and should 
not be used."

My converter is a new 40 amp Intellipower 9100 with a charge wizard.  It 
is supposed to be filtered but I thought I'd check.  My multitester  
indicated about 27 volts on the AC scale with the battery connected and 
the converter on, It appeared to give the same reading with the power to 
the converter switched off and on a 12 volt battery which was completely 
disconnected.  Can someone tell me what's happening here?  Two 
possibilities come to mind:  I am doing something completely wrong or 
my old inexpensive "multitester" does not do the same thing a modern 
"multimeter" does.

Any help would be appreciated.  I really don't want to fry the electronics in 
this water heater.

Dick
'62 Bambi