965f801a   
   From: Impedance@UgotOCD.invalid   
      
   Manufacturers never recommend two units in series but rather in parallel.   
   The minimum BTU requirements must be met or the burner will not ignite. Min   
   was 15,000 BTU and the new one is lower. People all look at the top end with   
   the scare tactics you are putting out. Top end is not a problem and lots of   
   reserve capacity is had with anything over 120,000BTU/h . Two showers and   
   the dishwasher,  simultaneously never bothers mine but rather the well pump   
   capacity.   
      
   3/4" gas line is all that is required. Just another tap off from the   
   manifold.   
      
   I have my heater backed up from my solar system electrical. My power has   
   never failed more than a few hours in severe storms.   
      
      
   ----------------"bob haller"  wrote in message   
   manufactuers sometimes recommend 2 tankless in series in cold   
   climates, and some of the issues have no easy work arounds.   
      
   take power line units which use the power line for powered venting.   
      
   a power failure in this type mean zero hot water during any power   
   failure.   
      
   and running new gas lines all the way back to the meter or even   
   possibly a complete new serice can cost thousands.....   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)