Baltimore Aircoil Company, Inc. (BAC) Maintaining the Mechanical Integrity of Evaporative Condensers – HVAC Insider
September 14, 2022
Evaporative condensers are an productive and cost-efficient heat rejection solution for various applications—food and beverage refrigeration, industrial equipment cooling, and HVAC. The units operate by condensing superheated refrigerant vapor inside of a coil that is regularly sprayed with h2o. As the h2o evaporates, admirers reject the heated drinking water vapor to the ambiance. By decreasing procedure condensing temperatures, evaporative condensers cut down compressor horsepower requirements, ensuing in vitality personal savings of up to 15% when when compared to air-cooled techniques.
For each individual inspection, it is important to doc the inspection course of action and all results, the day of the inspection, the name of the human being accomplishing the inspection, any actions taken. If any added potential actions or repairs are vital conduct for every manufactures suggestions or industry standards. Digital photos are a useful method for documenting existing ailments and demonstrating changes above time.
To make certain employee protection, all correct lock out-tag out techniques for the unit and any internet site security procedures need to be followed prior to starting inspection or servicing function. Additionally, measures need to be taken to ensure there is no refrigerant still left in the coil. This is ordinarily carried out by employing a vacuum program prior to getting into or servicing the condenser. Always observe field ideal tactics concerning the use of suitable PPE and “one in-a single out” methods.
Advised Inspection Applications
Most people today have a smartphone with a good electronic digicam, which is a beneficial software for photographing or recording inspection findings. Other advised equipment include things like an infrared thermometer, an infrared camera, an ultrasonic metallic thickness meter, a vibration meter (ultrasonic or accelerometer), a laser alignment instrument, a multimeter for voltage and amperage, a micrometer depth gauge, and a dye penetrant check kit to detect cracks. Importantly, a comprehensive inspection kit will also incorporate the manufacturer’s set up, operation, and upkeep manuals and lock-out / tag out varieties.
1. Adequate anchors and supports for device
A comprehensive upkeep software starts with a visible inspection of the fundamental structural integrity of the process. This phase features inspecting the condensing unit’s supports and anchors to guarantee that it is securely mounted. . An inspection should really also be designed of any improperly supported piping, which could overstress coil connections and trigger a leak. Each assistance must be visually examined, hunting for cracks, lacking or loose fasteners, and any corrosion.
2. Corrosion of enclosure, tubes, piping and supports
Condensers really should be inspected for corrosion at least on a yearly basis and more typically as problems demand. If still left untreated, pitting can degrade the wall thickness of a tube or pipe, maybe leading to leaks and burst pipes. Excessive tube scale causes missing condensing ability and decreased performance. Visually examine all seen coil surfaces with a flashlight or electronic digicam. When even further assessment is essential, specially of locations that may not be commonly visible, a versatile, lighted borescope can be practical. Wherever achievable, measure the depth of huge pits with a micrometer depth gauge.
3. Scale develop-up on tube bundle
Guarding from scale is critically significant to sustaining the potential of the condenser, which is why condensers should really be consistently inspected for scale make-up. Infrared cameras are productive for measuring thermal degradation thanks to scale. In Figure 1, the picture on the remaining demonstrates a 9-degree F variance because of to delicate scale establish-up the picture on the right demonstrates basically no temperature difference, indicating the coil is thoroughly clean.
4. Cracks in supporter assemblies
As a mechanical ingredient, admirer assemblies want to be inspected at the very least every year. Fan blades can split off and bring about destruction to encompassing areas. A loosened motor mount can result in a enthusiast assembly to slide, which may perhaps final result in substantial hurt to the condenser. During inspection, glimpse and listen for any vibrating areas — larger sheet steel sections will commonly be the most recognizable. Watch the supporter in operation, seeking for any vibration as it rotates. Listen for unexpected modifications in sound levels or tones, and visually examine the lover assemblies for cracks.
5. Shafts, bearings, motor mounts, belts, and fasteners
A thorough inspection contains detection of overheated bearings, belts, or motors making use of an infrared camera and conducting a visible research for cracked or frayed belts and lacking fasteners. A rotating ingredient may fall short so abide by recommended upkeep strategies in the manufacturer’s operations and servicing handbook to keep away from personal injury and mechanical challenges.
6. Scale or grime construct up in drift eliminators and the water sump
Visually examine the mist eliminators and basin for biological progress, scale establish-up, or dust accumulation. These disorders bring about minimized airflow, ensuing in enhanced operating temperature and pressure, which may induce the spray water pump to clog and therefore prohibit or halt the flow of water in excess of the coil bundle. If needed, drain the basin, take away any international substance and both cleanse or swap mist eliminators as necessary.
7. Safety gadgets
Check out that any basic safety units, such as vibration switches, are operating appropriately. Stick to the manufacturer’s guidance for the frequency of, and procedure for, tests every gadget. Malfunctioning or missing basic safety gadgets could end result in unsafe procedure of the device. For illustration, a disconnected vibration swap could are unsuccessful to detect a vibrating admirer assembly, which could result in catastrophic fan failure and mechanical harm.
8. Electrical connections
Wiring also wants to be inspected for unfastened connectors or indicators of electrical overheating (black marks) as very well as for melting or cracking wire insulation. Visually inspect electrical connectors and use an infrared camera to discover overheating electrical components that could fall short or catch fireplace. Contact an electrician to maintenance or switch faulty electrical components that clearly show signals of have on.
9. Spray nozzles
Visually check that spray nozzles are not plugged and are offering a uniform spray sample. Poor h2o spray to the coil surface area could final result in larger operating temperature and condensing force and compromise functionality. Always use spray nozzles from the primary tools maker to make certain best h2o coverage.
10. All isolation valves and purge valves
Isolation valves must be checked to ensure that they are working and in superior problem. Visually inspect the valves to make positive they are no cost from signs of main corrosion and take a look at the valves to make absolutely sure they run accurately — opening and closing effectively devoid of leaks. Replace valves that are malfunctioning or displaying too much corrosion.
Try to remember, do not wait around right until the condenser fails to carry out maintenance. To increase the functioning everyday living of your process, preventative upkeep is critical. Effectively-preserved machines will increase uptime and performance and support to maintain your procedure hygienic and harmless.