Resideo (Honeywell) AEL-222214 Automatic Expansion Valve – AEL 4.0 | 1-7 bar Constant Pressure, 1/4" × 3/8" ODF

Resideo (Honeywell) AEL-222214 is an automatic expansion valve (constant pressure valve). Its difference from a thermostatic valve: it works according to evaporating pressure, not superheat — it keeps the evaporator pressure constant at the set value. It opens when the load drops and throttles when the load rises; this keeps the evaporator pressure, and therefore its temperature, constant.

Constant Evaporating Pressure: Dehumidifier and Ice Machine Applications

According to the official Honeywell documentation, the AEL series is designed for systems with single-injection evaporators without a distributor: air conditioners, dehumidifiers, air dryers, water coolers and ice machines. The load in these applications varies greatly; while a thermostatic valve goes into hunting, a constant pressure valve keeps the evaporator stable and prevents freezing.

Technical Specifications (Official Honeywell Product Data)

• Model: Resideo (Honeywell) AEL-222214 | Valve Size: AEL 4.0
• Type: Automatic expansion valve — fixed orifice (3.5), internally equalized
• Nominal Capacity: 12.2 kW (R22) · 8.7 kW (R134a) · 8.6 kW (R404A) · 8.7 kW (R507A)
  at t₀ +4 °C / t𝒸 +38 °C, 1 K subcooling
• Evaporating Pressure Setting Range: 1 – 7 bar(a) | Factory setting 2.2 bar(a)
• Connections (ODF solder): Inlet 1/4" · Outlet 3/8"
• Max. Pressure: PS 25.5 bar(a) · test pressure PF 28 bar(a) | Max. ambient temperature 100 °C
• Dimensions: C 58 · D 36 · E 106 · F 54 mm | Weight: ≈0.16 kg — official dimensional drawing in the 2nd image
• Body: Hermetic construction, stainless steel head + stainless diaphragm welded under protective gas
• Compatible Refrigerants: All CFC / HCFC / HFC refrigerants — not for use with ammonia (R717)

• 🔧 Adjustment: The factory setting is 2.2 bar(a). Turn the adjusting screw in small steps and wait for the system to stabilize; lowering the pressure lowers the evaporator temperature.
• Where not to use it: This valve is not suitable for evaporators with a distributor or multiple circuits — an externally equalized thermostatic expansion valve (TXV) is used there.
• Cool the body with a wet cloth during soldering; keep the flame away from the adjusting spindle and diaphragm area.
• Family: The same series includes AEL 0.5 / 1.0 / 2.0 / 3.0 / 5 / 6 sizes; selection is based on capacity.