IV. Annual Lamp Replacement

CHECK LAMP OPERATION

The preferred method for checking lamp operation is to measure the current draw of the lamp using a clamp-on ammeter. To detect the low current of the UV lamp, the ammeter must be capable of measuring 100 mA and above. To prevent accidental exposure to

harmful UV germicidal light during this procedure, the location where the amperage measurement is taken must be in a separate compartment from where the UV lamp is installed. To measure the current draw of the lamp:

a. First, shut off power to the HVAC equipment.

b. Next, in the control panel for the HVAC equipment, locate the hot and neutral wires that were installed to provide power to the lamp.

c. Place the clamp-on ammeter around either the hot or neutral wire. Make sure the ammeter is set to read amps in the mA range. Again, make sure that the UV lamp – or light from it, if it were on – is not visible from where the ammeter is placed.

d. Next, turn the power to the HVAC equipment back on.

e. If the lamp has been installed correctly and is drawing power, the amp reading will be a minimum of 150 mA. For multiple lamps, the reading would be a multiple of this value, i.e., with two lamps installed, the amp reading will be at least 300 mA.

f. If the lamp is operating correctly, remove the ammeter from the wiring and put back any access panels that were removed during this procedure. If the lamp is not operating correctly, refer to the ‘Troubleshooting’ section of this manual.

Note: If other electrical components or accessories share the same circuit as the UV lamp(s), the current draw will be higher and the above method may not be an accurate indication of lamp operation.

The Aprilaire Ultraviolet Germicidal Lamp is designed for the lamp to be on at all times. After 9,000 hours of operation – 1 year of constant use – the effectiveness of the lamp inside the unit diminishes and needs to be replaced. Rarely will a lamp burn out in one year of continuous use; replacement is necessary because the lamp’s intensity decreases. Installation of the replacement lamp is best handled by a qualified HVAC Service Contractor.

LAMP REPLACEMENT INSTRUCTIONS (EXTERNAL & INTERNAL MOUNT UNITS):

a. Shut off power to the rooftop unit. Wait several minutes for lamp to cool before proceeding. Remove access panel(s) to the rooftop unit.

b. Remove Lamp from Unit. For External Mount Units, open the cover of the Unit Base, disconnect Lamp Retaining Bracket, and slide the Lamp to the large side of the keyhole slot and then pull straight out. For the Internal Mount Unit, simply disconnect Lamp Socket and remove Lamp.

c. Use alcohol to remove any dirt and/or fingerprints from the new Lamp. Insert Lamp into the unit and attach Lamp Socket to the Lamp.

Refer to ‘Troubleshooting’ section if the Lamp does not operate.

d. For External Mount Units, close and secure the cover of Unit Base.

e. Put access panels of the rooftop unit back in place.

f. Turn power to rooftop unit back on.

g. Refer to ‘Check Lamp Operation’ of the previous section to verify operation.

h. Record the date the lamp was replaced in this manual so that the date for next replacement is clear.

Under normal conditions, the Aprilaire Ultraviolet Germicidal Lamp should not require any maintenance other than annual lamp replacement.