4REF knowledge base
ServiceServiceFeaturedEvacuating a system: why microns matter, not minutesTimed evacuation is a myth. What counts is the micron level and a decay test — here is how to dry a system properly.Read article HVAC-R knowledge base
Practical know-how for professionals: evacuation, recovery, flaring, and choosing & servicing Wipcool, Fieldpiece and Elitech tools.
Choosing equipmentChoosing equipmentChoosing a vacuum pump: CFM, two stages and A2L refrigerantsBigger isn't everything. Here is what to look at: stages, ultimate vacuum and working with R32.TechniqueTechniqueA leak-tight flare: 45°, finish and tightening torqueMost leaks start at a bad flare. Three things to get right every single time.RegulationsRegulationsRefrigerant recovery under F-gas: no venting to atmosphereVenting refrigerant is banned. How to recover it safely and what Regulation 2024/573 changes.DiagnosticsDiagnosticsLeak detection: electronic detector, UV or nitrogen?Each method has its place. When to reach for an electronic detector, UV dye, or a nitrogen test.MaintenanceMaintenanceVacuum pump oil: when and why to change itSpent oil means a shallower vacuum and a shorter pump life. Simple rules that extend equipment life.Buying guideBuying guideHow to equip an HVAC-R service crew: the must-have listStarting out or building a second crew? Here is the kit you can't work without — in priority order.ComparisonComparisonWipcool vs Fieldpiece vacuum pumps — which to pick?Two strong brands, different priorities. We compare capacity, serviceability and price to ease the choice.Choosing equipmentChoosing equipmentSelecting and Installing Condensate Pumps — Draining Condensate from AC Units and Heat PumpsA condensate pump is the component that determines the reliability of the whole installation when no gravity fall is available. Below is a practical guide to sizing flow rate and lift height, installation, and the field mistakes to avoid.MaintenanceMaintenanceCleaning and Disinfecting Heat Exchangers — AC Condenser and Evaporator CoilsA fouled coil raises operating pressures, kills COP/EER and breeds biofilm. Below is a service procedure for condenser and evaporator coils driven by measured criteria, not by eyeballing.TechniqueTechniqueHard-Brazing Copper Refrigeration Pipe Under Nitrogen Purge (OFN)Brazing copper without a nitrogen purge (OFN) leaves a layer of oxide scale inside the pipe that later travels with the refrigerant and destroys the compressor. Below is field practice: flow, filler, technique and inspection.ServiceServiceCharging refrigerant correctly: weigh-in method vs superheat and subcoolingAn undercharged or overcharged system means a short compressor life and lost capacity. Here is when to trust the scale and when to verify the charge with superheat and subcooling.
Stay up to date with HVAC-R
New tools, guides and B2B offers — no spam, unsubscribe anytime.