Raypak NH - Manual (Page 23)

1. Estimate total length of supply and return loop.
Refer to table.
2. If multiple loops are used:
(A) Use multiple pumps and size return pipes
according to table; or
(B) Use one larger recirculating pump with
balancing valves on each return line.
3. First fixture on supply line must be a minimum
of 20 feet from the heater.
4. Supply line size must be 2" minimum. If not
possible, add a tank between heater and first
fixture.
TYPE NH - DUAL MODELS 514-1826
23
MINIMUM INPUT ADJUSTMENT
Model Types NH and WH have minimum input ratings as specified on their individual rating plates. Minimum
input controllers have been pre-set at the factory. Consult with factory representatives if a minimum input
problem should occur.