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AIR FILTERS
To maintain efficient operation, the air filters should be checked monthly and renewed as required. Because renewal intervals
may vary with environmental conditions and filter type, each unit is equipped with a filter clog switch which warns of restricted
air flow through the filter compartment by activating the 'Change Filter' alarm.
1) On downflow models the filters can be removed from the top of the unit, whereas on upflow units the bottom front panel
contains the filters.
2) Fit new filters, refit the unit front panel on upflow units and restore the power supply.
STEAM GENERATING HUMIDIFIER
Remove the unit front panels and examine the humidifier for any loose electrical connections. Retighten any loose connections.
Examine all pipes and connections for defects, damage and security of attachment.
Ensure that the steam generating canister is properly secured to the unit frame. Refit the unit front and side panels and restore
the electrical supply to the unit. Record and report any defects found during the inspection.
CHILLED WATER COIL
1) Remove the unit front panels and inspect the coil for defects, damage or corrosion.
2) Check that the coil fins are in good condition. If they are found to be bent, they should be carefully straightened using a
proprietary fin comb.
3) Inspect the pipework connections for any signs of leaks.
4) Refit the front panels and restore electrical supply to the unit.
5) Record and report any defects found during the inspection.
CHILLED WATER VALVES
1) Remove the unit front panels.
2) Visually inspect the valve(s) for damage and ensure that the connections are not leaking.
3) Ensure that the valve(s) are securely mounted in position.
4) Ensure that the actuator(s) are securely fitted to the valve body.
5) Refit the unit front panels and restore the electrical supply to the unit.
6) Record and report any defects found during the inspection
ELECTRICAL PANEL
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INSPECTION AND FUNCTIONAL CHECKS
Open the unit front, inspect the electric panel for any damage or loose electrical connections and re-tighten as necessary.
Note: -The functioning of all control circuits can be tested by actuating each of the main functions, by adjusting the set points.
COOLING FUNCTIONAL TEST
Select a set point for a temperature of 6oC below room temperature.
a) A call for cooling should be observed.
b) The chilled water valve should open, and the equipment should begin to cool.
c) A high temperature alarm may enunciate. Disregard it.
Return the set point to the room temperature.
REHEAT FUNCTIONAL TEST
Select a temperature set point for 6oC above the room temperature.
a) A call for heating should be observed.
b) Both heating contactors should energise, and the heating elements should begin to heat.
c) Disregard the low temperature alarm.
Return the set point to the desired temperature.
HUMIDIFICATION FUNCTIONAL CHECK
Set the humidification to 10%RH above the room humidity reading.
a) For a steam generating humidifier, you will immediately hear clicks as it energises. After a short delay, the canister will fill
with water. The water will heat and steam will be produced.
Return the humidity setting to the desired room relative humidity setting.
