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ORANGE COUNTY 230913-2 <br /> <br />Emergency Management Warehouse Building Dehumidification Instrumentation and Control <br /> Devices for HVAC <br /> <br />Temperature Sensors: 1 <br /> 2 <br />Space Sensors: Space sensors shall be negative temperature coefficient thermistor type within wall-3 <br />mounted enclosures with blank covers and no temperature display. No setpoint adjustment by occupants 4 <br />shall be provided. Select thermistor resistance and temperature/resistance curve for maximum accuracy in 5 <br />the range of 50-100 deg F. 6 <br /> 7 <br />Indoor Air Relative Humidity Sensors: Analog type with polymer element for comfort conditions monitoring and 8 <br />platinum element for critical areas including laboratories, hospital procedure rooms, etc. Space sensors shall have 9 <br />blank covers and no humidity display and no setpoint adjustment unless specifically indicated on the drawings. Duct 10 <br />sensors shall meet the requirements specified below for outdoor relative humidity sensors. 11 <br /> 12 <br /> 13 <br />ELECTRIC CONTROLS ELEMENTS 14 <br /> 15 <br />Low-Voltage, On-Off Thermostats: NEMA DC 3, 24-V, bimetal-operated, mercury-switch type, with adjustable or 16 <br />fixed anticipation heater, concealed set-point adjustment, 55 to 85 deg F set-point range, and 2 deg F maximum 17 <br />differential. 18 <br /> 19 <br />Line-Voltage, On-Off Thermostats: Bimetal-actuated, open contact or bellows-actuated, enclosed, snap-switch or 20 <br />equivalent solid-state type, with heat anticipator; listed for electrical rating; with concealed set-point adjustment, 55 to 21 <br />85 deg F set-point range, and 2 deg F maximum differential. 22 <br /> 23 <br />Electric Heating Thermostats: Equip with off position on dial wired to break ungrounded conductors. 24 <br />Selector Switch: Integral, manual on-off-auto. 25 <br /> 26 <br />Remote-Bulb Thermostats: On-off or modulating type, liquid filled to compensate for changes in ambient 27 <br />temperature; with copper capillary and bulb, unless otherwise indicated. 28 <br />Bulbs in water lines with separate wells of same material as bulb. 29 <br /> 30 <br />Bulbs in air ducts with flanges and shields. 31 <br /> 32 <br />Averaging Elements: Copper tubing with either single- or multiple-unit elements, extended to cover full width 33 <br />of duct or unit; adequately supported. 34 <br /> 35 <br />Scale settings and differential settings are clearly visible and adjustable from front of instrument. 36 <br /> 37 <br />On-Off Thermostat: With precision snap switches and with electrical ratings required by application. 38 <br /> 39 <br />Modulating Thermostats: Construct so complete potentiometer coil and wiper assembly is removable for 40 <br />inspection or replacement without disturbing calibration of instrument. 41 <br /> 42 <br /> 43 <br />FINAL CONTROL ELEMENTS AND OPERATORS: 44 <br /> 45 <br />Control Dampers: Provide dampers with parallel blades for 2- position control, opposed blades for modulating 46 <br />control. Dampers shall be in accordance with Section 233300. 47 <br /> 48 <br />Control Valves: 49 <br /> 50 <br />Valve bodies shall be designed for not be less than 125 psig working pressure or 150% of the operating 51 <br />pressure, whichever is greater. Class 125 bronze body valves and Class 150 stainless steel valves shall 52 <br />comply with ASTM B16.5. Cast iron components shall meet the requirements of ASTM A126, Class B. 53 <br /> 54 <br />Select and size control valves as hereinafter specified and submit complete valve selection list with shop 55 <br />drawings. 56 <br /> 57 <br /> 58 <br /> 59 <br /> 60 <br />DocuSign Envelope ID: 7668B866-6C26-485C-9A45-DAAB5D4BD951