Accurex Make Up Air Unit Maintenance Instructions

Keeping air units in peak condition is an essential part of being a technician. Service calls can go well when you know exactly what maintenance you need to accomplish. If you need Accurex make up air unit maintenance instructions, follow our tips below. 

Routine Maintenance

V-Belt Drives

• Inspect V‑belt drives regularly for wear, proper tension, alignment, and dirt buildup.
• Check belt tension by measuring deflection and verify alignment using a straight edge across both sheaves.
• Improper tension or misalignment can lead to premature belt wear, excessive noise, slippage, overheated sheaves, and bearing failure.
• Never pry belts on or off; loosen tension fully and remove belts by lifting them off the sheaves.
• Replace all belts on multi‑groove drives at the same time, and never install new belts on worn sheaves—replace sheaves as needed.

Motors

Motor maintenance typically includes only cleaning and lubrication. Some best practices to keep motors in peak condition include:

• Removing dust and grease build-up on the motor
• Cleaning the exterior
• Don’t allow water or solvents to enter the motor or bearings 
• Never spray motors and bearings with steam, water or solvents

Wheels

Supply wheels generally require minimal maintenance when handling clean air; however, periodic oil or dust buildup can happen and cause imbalances. When this happens, the wheel and housing should be cleaned for proper operation.

Bearings

• Lubricate bearings prior to extended shutdowns or storage
• Rotate shaft monthly to prevent corrosion 
• If fan is stored more than three months, purge the bearings with new grease prior to start-up

Filters

Maintaining filters is a quick and easy process. Whether the unit has permanent or disposable filters, follow any of these maintenance tips:

• Filter maintenance typically involves routine cleaning or replacement
• Aluminum mesh filters can be washed with warm, soapy water and may be treated with an adhesive spray to improve efficiency
• Disposable filters should be replaced when light no longer passes through them
• Always reinstall filters according to the airflow direction arrow on the filter
• Replacement filters must match the original manufacturer and size specified for the unit

Evaporator Coolers

Proper cooling media maintenance is essential for maintaining evaporative cooling efficiency and preventing mineral buildup that can reduce system performance and lifespan.

• Cooling media should be lightly brushed in an up‑and‑down motion while flushing with water to minimize mineral buildup
• Heavy mineral accumulation requires cleaning or replacing the media and increasing the water bleed‑off or drain‑and‑fill rate
• Cooling media typically lasts 3 to 5 years, depending on water quality and bleed‑off or drain‑and‑fill practices

Cooling Coils

Always follow the coil manufacturer’s cleaning recommendations and use caution when venting coils, as high‑pressure or high‑temperature fluids can cause serious injury. 

• Inspect coils for corrosion or leaks, repairing any leaks as needed
• Clean dirty coil surfaces from the leaving air side to flush debris out
• Inspect and clean the drain pan to prevent algae and biological growth

Chilled Water Coils

• Test the circulating fluid for sediment, corrosives and contaminants
• Make sure fluids are properly filtered and at accurate levels
• Drain/flush coils during winter to protect against freezing

Blowing-Out Coils

• Step 1. Close the valves on both the supply and return lines
• Step 2. Open the drain valves and/or drain plug. Remove vent plug to allow the coil to drain faster
• Step 3. After the coil is fully drained, connect a blower to the caps. Don’t connect the blower to the air vent or drain plug
• Step 4. Close the vent plug on the header that the blower is connected to. Open the drain valve or cap on the other header
• Step 5. Turn on the blower for 30 minutes and place the mirror at discharge. If the mirror fogs up, repeat the procedure until no fog appears on the mirror
• Step 6. After drying the coil, wait a few minutes then repeat step 5
• Step 7. Leave the drains open and don’t install the plugs until the beginning of the colder season