PART 1 GENERAL

A. SCOPE

1. Furnish an air/water atomizing humidification system as specified here, on the equipment schedule and engineering drawings.  

2. Operation of the system shall be controlled automatically to maintain ___% relative humidity (R.H.) at ___°F with a tolerance of +/-___R.H. with outside design temperature of ___°F and ___%R.H.  

3. Warranty system for a period of one year from date of beneficial use by the owner.  

4. Provide owners equipment and manual detailing installation, startup, operation and maintenance.  

5. The manufacturer shall guarantee in writing that the system will maintain the desired level of R.H. as stated above, based on the design information provided.  

PART 2 EQUIPMENT

A. CONTROLS

B. CONTROL SECTIONS

1. Each humidification system shall have two control sections, consisting of a supply water control section and a compressed air control section. System controls shall be provided complete with space humidity sensors, or the system controls shall be supplied to accept the building management system (BMS) signal, as stated in the project specifications.  

2. The water control section shall consist of a gate valve, pressure regulator with strainer, pressure gauges, and three-way solenoid valve. Water pressure to the control section shall be 50 psi and water pressure to the atomizing heads shall be maintained at 40 psi. For potable water, the water control section shall be fabricated from Type "L" copper, and brass components. For deionized water, the water control section shall be fabricated from 304 and 316 stainless steel components. The water control section shall be factory assembled and tested prior to shipment.  

3. The air control section shall consist of a gate valve, pressure gauge, two-way solenoid, pressure regulator with gauge and strainer and an air pressure switch. Compressed air pressure to the control section shall be 60 psi and air pressure to the atomizing heads shall be maintained at 30 psi. The compressed air control section shall be fabricated from Type "L" copper and brass components. The compressed air control section shall be factory assembled and tested prior to shipment.  

4. All control section solenoid valves shall be 24, 120 or 230 volt single phase.  

5. Water piping, field installed, shall be Type "L" copper, PVC or stainless steel, as stated on the engineering drawings.  

6. Air piping, field installed, shall be Type "L" copper, PVC or stainless steels, as stated on the engineering drawings.  

C. ATOMIZING HEADS

1. Atomizing heads shall be of the compressed air and water internal atomizing type. External mix heads are not acceptable. Atomizing heads with external appendages are not acceptable. Internal atomization design shall use no more than 0.12 SCFM of compressed air at 30 psig for each pound of water per hour humidity required. Atomization shall produce water droplets averaging no greater than 7.5 microns in diameter.  

2. Atomizing heads shall be of the self-cleaning type, incorporating a spring loaded stainless steel cleaning needle, neoprene diaphragm, and silicone water valve seat. The stainless steel needle shall automatically clean the water atomizing orifice every time the humidifier cycles, displacing any mineral deposits that may form. The silicone water valve seat shall prevent dripping, spitting and ambient contamination of the water.  

3. Atomizing heads shall be of materials not adversely effected by the purity or aggressiveness of the water, easily disassembled for servicing with self-cleaning and purging feature to provide a complete drip-free operation. Average droplet size will not exceed 10 micron at 100% output and will decrease as the system modulates downward. Documentation of droplet size available on request. 

D. OPERATING SEQUENCE

1. On a fall in relative humidity in the space, the humidistat will activate the system. Should the humidity level exceed the setting of the safety humidistat, the water will be shut off from the system.  

2. A power failure or compressor failure will automatically shut the system down.  

3. If water pressure is lost or reduced, the atomizing heads will sputter. Complete loss of the water supply will cause the atomizing heads to blow air only.  

PART 3 EXECUTION

A. GENERAL

1. Install system(s) as detailed on the drawings and/or as recommended by the manufacturer. Shop drawings, indicating piping sizes and atomizing head capacities, shall be provided by the manufacturer. Manufacturer's representative shall provide analysis, design and startup support of the custom engineered humidification system(s).  

2. Compressed air supplied to the air control section manifold of the humidification system shall be at ambient temperature, and supplied via a moisture separator, trap and a coalescing filter capable of cleaning the air to 0.5 micron.  

3. Water supplied to the water control section of the humidification system shall be at ambient temperature, potable, filtered and treated, or deionized.  

Dual Pneumatic Systems are manufactured by Herrmidifier,
Trion Inc., 101 McNeill Road Sanford, NC 27330