Air Conditioning

15 articles

• AC Annual Service UK: Filter, Coil & Refrigerant Check
  Full annual service checklist: filters, evaporator/condenser coils, condensate, refrigerant pressure (superheat/subcooling), F-Gas log update; mandatory leak check frequency by CO₂e threshold; commercial systems twice-yearly; service report format
• AC Condensate Drainage: Pump Sizing & Discharge Guide UK
  1–2 litres/hour condensate from 3.5 kW unit; primary vs secondary drain; 1:50 minimum gradient; MDPE/ABS pipe (not copper); discharge hierarchy (soil stack preferred); condensate pump head/flow sizing; check valve requirement; Part H compliance
• AC Electrical Supply Requirements: BS 7671 UK Guide
  BS 7671:2018+A2:2022; dedicated circuit sizing; Type C MCB for motor inrush; cable sizing steps; 30 mA Type A/F RCD for outdoor equipment; lockable outdoor isolator (IP44/65); earthing for TN-C-S/TT; Part P notification
• AC Energy Efficiency: SEER & SCOP Ratings Explained UK
  SEER for cooling, SCOP for heating; ErP label reading (Class A minimum SEER 3.60, SCOP 3.40); running cost calculation; heat pump vs gas cost comparison; EPC impact; AIA replaced ECA scheme for commercial AC
• AC in Listed Buildings: Planning Consent & Installation Guide
  Listed Building Consent required for any works; working with conservation officers; fan coil and cassette concealment strategies; reversible fixings; Historic England/HES guidance; Conservation Area outdoor unit rules; Scotland/Wales/NI equivalents
• Air Conditioning & Part F Ventilation Requirements UK
  Part F:2021 ventilation requirements; recirculating AC does not satisfy ventilation; MVHR interaction; SAP 10.2 AC declaration; Part L SEER minimums; CIBSE TM65 embodied carbon methodology
• Air Conditioning Permitted Development Rules: UK Siting Guide
  GPDO 2015 Schedule 2 Part 14 Class A conditions; 1 m boundary setback; no highway-facing walls; BS 4142 noise assessment; flats and listed buildings excluded from PD; Conservation Area rules; Scotland/Wales/NI differences
• F-Gas Regulations 2024: Certification & Leak Checks UK
  UK F-Gas Regulations; CO₂e charge calculation; leak check thresholds (5/50/500 tonne CO₂e: quarterly/monthly/semi-annual); Category I/II technician certs via City & Guilds 2079; logbook requirements; HFC phase-down schedule; refrigerant recovery obligations
• HVAC Commissioning & Handover: F-Gas & Airflow Checks
  Nitrogen pressure test; two-stage evacuation to <500 microns; weigh-in refrigerant charge (±10g scales); top-up from pipe length tables; 8–12°C supply/return differential; airflow balancing ±10%; F-Gas label and log; mandatory leak test thresholds; customer handover pack
• Multi-Split Air Con Design: Capacity & Piping Limits UK
  Outdoor unit capacity vs sum of indoor units; 80–90% diversity; Refnet branch junction design; total equivalent length limits; oil trap requirements; refrigerant top-up calculation from pipe lengths; mixing indoor unit types; 10-step commissioning sequence
• Portable AC vs Split System: Performance & Cost Guide UK
  Single-duct portables create negative pressure negating cooling; EER 2.0–2.5 vs 3.5–5.0 for splits; noise 52–58 dB vs 19–42 dB; running cost comparison; when portables are justified; installer opportunity converting portable users
• R32 vs R410A vs R290 Refrigerants: GWP & Flammability UK
  R32 (GWP 675, A2L), R410A (GWP 2088, A1, being phased out), R290 propane (GWP 3, A3), R1234yf (GWP 4, A2L); ASHRAE flammability classes; A2L installation precautions; R290 charge limits in occupied spaces; phase-down timeline
• REFCOM Certification UK: F-Gas Registration & Licence Guide
  REFCOM company certification for F-Gas; annual returns by 31 March; REFCOM vs REFCOM Elite; Contractor Competency Scheme for natural refrigerants; how to verify contractor status; record-keeping requirements for refrigerant purchases and recovery
• Split System AC Installation Guide: UK Sizing & Positioning
  Indoor unit clearances (15 cm sides, 20 cm ceiling); outdoor unit siting and vibration isolation; pipe sizing (6.35 mm liquid/9.52 mm suction); flaring and nitrogen pressure test; evacuation to <500 microns; condensate drainage (1:50 fall); electrical supply (dedicated circuit, Type C MCB, Type A RCD, local isolator)
• VRF/VRV Systems: Design, Piping & Controls Guide UK
  VRF vs VRV naming; 2-pipe vs 3-pipe heat recovery; BCU function; equivalent length limits (165 m total, 50 m height); Y-junction vs header branch kits; BACnet/Modbus/LonWorks integration; commissioning software; appropriate for 5+ zones