Control Of Duct Or Plenum Saturation; Figure 4. Condensate Drain Pan - Nortec NHPC Engineer's Manual

Maximum capacity of the NHTC/NHPC humidifier can be limited through the keypad.
C. CONTROL OF DUCT OR PLENUM SATURATION
(1) NORTEC always recommends the use of a high limit humidistat set at 85% relative
humidity in combination with an air-proving switch to assure air movement. Both of
these controls are wired in series across the primary control terminals of the humidifiers
so that should either of these conditions not be satisfied the humidifiers cannot operate.
(2) Low temperature, shallow ducts or branch ducts might require a field supplied
condensate drain pan and should be accessible to service and inspection (See
Figure 4.).
(3) The most effective method of ensuring controlled absorption distances is to install a
modulating high limit humidistat. By controlling the down stream [after distributor(s)]
humidity levels and modulating the humidifier's output, one of the variables affecting
absorption distance is now a constant. NORTEC recommends modulating high limit
humidistats on all economizer systems, VAV, VVT, and systems, which are primarily
cooling.
NOTE

Figure 4. Condensate Drain Pan

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