Refrigerant Charging and Service Procedures for Air Conditioning — 2nd Edition - HVAC School

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Refrigerant Charging and Service Procedures for Air Conditioning — 2nd Edition

April 17, 2021

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HVAC School – For Techs, By Techs

HVAC School – For Techs, By Techs

Real training for HVAC ( Heating, Ventilation, Air Conditioning and Refrigeration) Technicians. Including recorded tech training, interviews, diagnostics and general conversations about the trade.

Premature Coil Failure in Ductless Mini-Splits & VRF Equipment – Short #303

byBryan Orr

In this short podcast, Bryan and Roman discuss premature coil failure in ductless mini-splits and VRF equipment.

These coils are susceptible to a few different types of corrosion. Warmer coil saturation temperatures and shorter runtimes result in lower latent capacity; whatever moisture is on the coil dries on the coil instead of draining out. Minerals and chemicals (including chlorides from bleach or cleaners) interact with the coil and may cause corrosion, including formicary (“ant’s nest”) corrosion. Leaks and corrosion may be environmental rather than entirely attributable to manufacturer defects.

Technicians can use proper cleaners with correct dilution ratios and rinse the coils. In situations where the environment contributes to coil corrosion, such as with substances off-gassing or dealing with coastal air, we will need to dilute the pollutants by ensuring proper ventilation. Dilution needs to be intentional, especially in hot-humid climates, and ventilating dehumidifiers with good filtration may be a good move. Source control and filtration are also good mitigation strategies, and clear, open client communication can help clients understand the problem and make informed decisions about their HVAC system.

This episode contains embedded sponsor messages from Refrigeration Technologies, Carrier, NAVAC, and Fieldpiece.

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Coil Corrosion w/ Kevin Hart and Bryan Orr
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Premature Coil Failure in Ductless Mini-Splits & VRF Equipment – Short #303

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VIPER SNIPER UNIVERSAL AEROSOL TRIGGER SPRAYER The Viper Sniper is an ergonomic trigger sprayer that fits all standard aerosol cans. Designed for comfort and control, it reduces finger fatigue and delivers a smooth, consistent spray, especially in those hard-to-reach areas. Features quick-attach side clips for easy, secure use. Compatible with all standard aerosol cans —including Viper Aerosol Coil Cleaner and Coil Coating Spray. Fits Any Aerosol Can Full Hand Ergonomic Grip Easily Clips On and Off 2 Sprayers per pack

VENOM PACK CONDENSER PURE CONCENTRATE COIL CLEANER

VENOM PACK CONDENSER PURE CONCENTRATE COIL CLEANER Venom Pack Condenser Cleaner is a high foaming pure concentrate liquid designed to tackle the toughest soils. The proprietary blend of specialty detergents will liquify heavily embedded grease and grime to restore heat transfer and increase the efficiency of the coil.

Viper Condensate Pan and Drain Treatment

Viper Condensate Pan and Drain Treatment Viper Condensate Pan and Drain Treatment is a sprayable gel. It coats the pan, p-trap and drain piping with a lubricative film to improve flow and prevent future soil adhesion. The slow dissolving enzyme gel will outperform and outlast conventional tablets and strips.

Nylog Blue Gasket -Thread Sealant for AC/R Systems

Nylog Blue Gasket -Thread Sealant for AC/R Systems One drop of Nylog on your rubber hose gaskets prior to attaching your core tools, hoses or vacuum gauge will assure that things do not bind or leak during evacuation. Derived from refrigeration grade lubricants. Non-hardening, non-drying fluid which bonds tenaciously to many different substrates. Typically, one drop of Nylog can be stretched about three feet before breaking.

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