Aurora Star Tech https://validator.w3.org/feed/docs/rss2.html HVAC Error Codes & Diagnostic Codes HVAC Troubleshooting Guides Rinnai Tankless Water Heater: CO sensor voltage check (PCB connector C1) Rinnai Tankless Water Heater: Water leaking from pump housing Noritz Tankless Water Heater: Cleaning ignition and flame rods – Noritz Refrigeration: Won’t start cycle Refrigeration: Works, then warms up (repeating) Refrigeration: Zeotropic (400-series) system performing poorly after a vapor charge or after a large leak Refrigeration: Water overflow / drain pan full / condensate pump alarm Refrigeration: Won’t cut in / won’t cut out Refrigeration: Vacuum rises then levels off above 500 microns Refrigeration: Vacuum won’t reach target or rises steadily after isolating Refrigeration: Valve won’t open on warm start / long pull-down Refrigeration: Uneven oil levels between compressors Refrigeration: Unit runs excessively long or continuously Refrigeration: Unit will not run Refrigeration: Tube pitting or scaling Refrigeration: TXV chatters/opens on off cycle (display case door openings) Refrigeration: Uneven coil temperatures, part of coil warm Refrigeration: Suction pressure/temperature drops too low, system cycles off early, coil freezes Refrigeration: System pressures don’t match P/T chart / high head with normal load Refrigeration: Thermal overload trips repeatedly Refrigeration: Stuck compressor Refrigeration: Suction line heavily frosted at start-up, compressor struggles to start, possible slugging Refrigeration: Sight glass bubbles Refrigeration: Sight glass shows bubbles Refrigeration: Starved evaporator / low capacity Refrigeration: Runs all the time, too cold Refrigeration: Runs all the time, too warm Refrigeration: Short cycling Refrigeration: Runs all the time Refrigeration: Runs all the time, temp normal Refrigeration: Refrigerant migration / flooded compressor after power failure Refrigeration: Refrigerant/oil leak at shaft Refrigeration: Repeat compressor burnout Refrigeration: R-410A charged into R-22 components Refrigeration: Recovery slow Refrigeration: Refrigerant loss with no visible leak Refrigeration: Pressure/temperature control faults (refrigerators, coolers, freezers) Refrigeration: Product partially thawed / ice crystals on product; box warms during defrost Refrigeration: Pump won’t pull a deep vacuum Refrigeration: Overheating / burnout, metal chips in system Refrigeration: Pressure drops over 1 h / 24 h Refrigeration: Pressure rises ≥10 psi within 5 min after recovery Refrigeration: Oil-pressure control trips Refrigeration: One case too cold / too warm; erratic cycling Refrigeration: Overfilled recovery cylinder, rising ambient Refrigeration: Oil drained is dark, pungent, has metal chips Fast, Reliable Heating and Cooling Repair You Can Trust Blog