Armstrong EHU-704 - Manuals

INSTALLATION 4) MOUNTING THE HUMIDIFIER MODEL EHU-701: Making sure the unit is level, hold it against the mounting surface and mark the hole pattern. Attach the units to studs or other sturdy structure with the two 3/8"× 1½" lagscrews provided. MODELS EHU-703 & 704: Making sure the mount...

6) WATER FILL SUPPLY Connect the unit to the building water supply (25 to 125 psig pressure). Install a shut-off valve near the humidifier. Connect the water supply to the 3/8" tube compression fitting on the fill valveadaptor. NOTE: ORDINARY (POTABLE) TAP WATER IS RECOMMENDED. IF POTABLE WATER ...

c. Use the template provided to cut installation holes in the duct for the dispersion tube as in Figure 7-2 (and optional drain tube,Figure 7-3). d. Insert the dispersion tube into the duct so the holes face upward. Fasten the mounting plate to the outside of the duct with sheet metal screws. If the...

CONTROL WIRING NOTE: Wiring to the low-voltage controls should not run in the same conduits as the power supply wiring because faulty signals could result.The use of either a metal conduit or shielded wire is required for all the control and / or safety wiring.When using metal conduit, the conduit m...

Wall Mounted Control Humidistat: Wall-mounted humidistats are usually installed 4 ft. to 5 ft. above floor level. Often, the best location isbeside a thermostat that controls temperature in the same space that is to be humidified, if that loca-tion meets the following criteria: • The control humidis...

Duct Mounted Control Humidistat: Duct-mounted control humidistats are also available for installation where sensing and control of returnair or exhaust air ducts is preferable. (Figure 10-1) Please refer to manufacturer's recommendations for further information on the location, mounting, andoperatio...

12) AUDIBLE ALARM There is an external alarm circuit provided. When an alarm condition is detected in the diagnosticroutines, a relay contact closes allowing activation of an external Class II device connected between terminals 27 & 28. This circuit is rated to 1 amp. 12 Main ControlHumidistat H...

INSTRUMENT PANEL The Mode select button is depressed for approximately ½ second to switch both the "display mode selected" indicator and the 3 MODE BUTTON, digit display between: INDICATOR, -DEMAND- % of humidistat control range. and DISPLAY -CURRENT- actual current in amps. -% POWER- ratio ...

START-UP PROCEDURE FOR ARMSTRONG SERIES EHU-700 HUMIDIFIERS The following steps should be performed on all newly installed Series EHU-700 Humidifiers to ensurethat the humidifier and the entire humidification system functions correctly. BEFORE TURNING ON THE POWER Figure 14-1 1) Examine the wiring a...

15) Verify that all of the input/output circuits are functioning properly by entering the input/output diagnostics mode. Press the mode button until the diagnostics indicator lights and wait ten seconds. The unit will do a complete self-diagnostic check. See CO in the diagnostics section of this man...

TROUBLESHOOTING GUIDE CAUTION!: Disconnect the electric power supply at the circuit breaker or switch whenever theunit is to be inspected or serviced. DO NOT USE THE TANK ON/OFF SWITCH ON THE HUMIDI-FIER BECAUSE THIS SWITCH DISCONNECTS THE STEAM GENERATOR TANK ONLY. PRINCIPLE OF OPERATION - AN OVERV...

A high-water float switch prevents water carry-over into the duct due to an excessive water level in thetank. When the high water limit is reached the HIGH WATER light comes on and the fill valve isblocked until some water is boiled away and the water level drops. This is common during startup. Ifth...

Monitoring Current: While the unit is filling, the current should increase. As the current approaches the maximum rating ofthe unit, it increases more slowly, especially in higher capacity units. With the tank on, and the fill anddrain circuits idle, the current should fall slowly. When the unit is ...

EHU-700 DIAGNOSTICS THE Series EHU-700 has built in diagnostics to detect system problems early, before they becomesevere. If possible, the diagnostic routine performs corrective measures. If necessary, the unit is shut-down and a dry contact is closed to enable a remote alarm. The diagnostic messag...

WATER QUALITY AND TREATMENT FOR EHU SERIES HUMIDIFIERS GENERAL Series EHU 700 electronic humidifiers use ordinary tap water in their operation. The quality of thiswater affects both the operation and the maintenance of the humidifier. How the EHU works: The EHU is an electrode boiler. When no water ...

Results: -Excessive time needed to reach set point during star-up.-Poor humidity control. Remedy: -Add 1/2 teaspoon of Epsom salts to the fill cup. After start-up the automatic drain program should maintain the unit at full capacity.-If problem persists, contact the factory. WHEN WATER CONDUCTIVITY ...

25 See Drawings on Page 28 EHU-701, -703, -704 Series Electronic Steam Humidifier Repair Parts Item Part No. Description Used On *1A D4417 1 Ph Low Voltage 120,208,240,277 Volts 701 *1B D4418 1 Ph High Voltage w/Barrier 380,480,600 Volts 701 *2A D4415 3 Ph Low Voltage (208, 240, 277 volts) 701 *2B D...

26 Item Part No. Description Used On 15 B2717 Drain Valve Assembly w/ Hose & (2) Clamps 701,703,704 16A B2582A-1 Float Switch Assembly 701,703,704 16B B2582A-2 Float Switch Assembly (Far Tank) 704 17A B4482 Fill Valve w/Flow W asher & Straight 3/8" Compression Fitting 701 17B B4480 Fill ...

27 Electrical Parts Item Part No. Description Used On 46 C2059 Display PC Board 701,703,704 47A A22925 Control PC Board Less Current Module 701 47B A22926 Control PC Board Less Current Module 703,704 48A B2895-7 CM-7 Current Module 701,703,704 48B B2895-12 CM-12 Current Module 701,703,704 48C B2895-...

MAINTENANCE RECOMMENDED MAINTENANCE SCHEDULE 1 TO 2 DAYS AFTER 1) Check unit operation. START UP 2) Look in drain pan for leaks.3) Check steam piping for leaks.4) Observe duct low points for signs of poor humidity distribution.5) Be sure unit is draining freely by pushing the manual drain button (th...

If the electrodes begin to disintegrate, the tank may turn black or red, and arcing or flashing may be visible inside the tank while it is operating. IF YOU NOTICE EXCESSIVE ARCING, SHUT THE UNIT OFF AND CALL THE FACTORY BEFORE RE-STARTING UNIT. To replace the electrodes, please refer to the "Ta...

STEAM GENERATOR CHEMICAL CLEANING PROCEDURE This procedure is intended as a guide only for the chemical cleaning of the generator in all EHU mod-els. Read and follow label directions on any cleaning product. Check local codes before disposing ofchemicals. Caution: Muriatic acid can cause severe chem...

TANK DISASSEMBLY, CLEANING, AND ELECTRODE REPLACEMENT MODELS EHU-703 AND 704, SINGLE AND THREE PHASE 1) Using a 7/16" wrench, disconnect the jumper wires from the steam generator. 2) Remove 24 metal clips by pushing gently on top of each clip with a screwdriver while cupping the clip with the ot...

b) While the tank is out, look into the lower end of the tank. Make sure the drain screen is in place. Also check for accumulations of lime at the bottom of the tank. Refer to "Steam Generator Disassembly" and "Cleaning Procedure" sections to rectify these problems. 3) If the tank dr...

HUMIDISTAT DATA AUTOCAL PROCEDURE 1. Measure the room humidity near the humidistat with an accurate hygrometer.2. Turn the humidistat set point dial to match the reading of the hygrometer.3. Push and hold the Autocal button for more than 3 seconds or until the internal red light turns On and Off. SE...

DIMENSIONS Figure 37-1. Dimension drawing. Duct Humidistat Note: Specifications and equipment are subject to change without prior notice. TABLE 5: SENSOR CHARACTERISTICS Voltage between black and white wire, terminals #6 and #7 37 WiringFrom Top "Autocal" Button(Invisible) WiringFrom Back Se...

AIR SUPPLY HIGH LIMIT HUMIDITY SENSOR The A 17898 (H270) includes a high limit circuit. This allows the use of a second humidity in the supply air. Input signalgoes to terminals #8 on the humidistat. High limit set point ispreprogrammed at 85%. It can be readjusted using theA19517 service tool. If y...

APPLICATION EXAMPLE Steam humidification system controlled by a 0 to 10 Vdc valve wired to output #1. Remote humiditydisplay using 0 to 5 Vdc signal is wired to output #2. The humidity sensor is located in the return airduct. A proportional high limit humidity sensor is installed in the supply duct....

Dimensional Information Limited Warranty and Remedy A H Q A H I S B B M K E G EHU-704 R K K E E M M EHU-703 EHU-701 S J J D D L L C Side Side P Conn. for Dispersion 2" ID Hose Conn. for Dispersion 1-1/2" ID Hose Front in mm in mm in mm "A" W idth 18 457 19-1/2 495 33-1/2 851 "B&#...