Parts for your 2001 Ford Mondeo-Tx valve

2001 Ford Mondeo TX Valve: What it does, where it lives, and when to service it

Yes, the 2001 Ford Mondeo (Mk3) uses a thermal expansion valve (TX valve/expansion valve) at the evaporator inlet. This setup is documented in Ford’s Workshop Manual (HVAC, section 412-00), which specifies a metering valve at the evaporator rather than a fixed orifice tube. Ford’s official parts catalogues (e.g., Microcat/ETIS) list a “Refrigerant Expansion Valve” for Mondeo from late 2000 onwards, with superseding part numbers in the 1S7H-19D734-xx family. Major A/C catalogues from Hella/Behr and Nissens also supply a dedicated TX valve for the 2000–2007 Mondeo platform, confirming fitment.

The TX valve’s job is to meter how much liquid refrigerant enters the evaporator, using temperature and pressure feedback to hold a small, controlled superheat. That keeps the evaporator cold without letting liquid slug the compressor. When it’s behaving, you get steady vent temps, good demist performance, and no evaporator icing.

Common signs the TX valve is on the way out include weak cooling at idle but better at road speed, vent temps that hunt hot-cold-hot, frosting right at the valve or the first section of the evaporator line, or unusual hissing from the dash area. A valve stuck too closed starves the evaporator (low suction pressure, lines may frost), stuck open floods it (higher suction pressure, lazy cooling).

Replacement and service advice for a 2001 Mondeo TX valve:

• Always have the refrigerant recovered and recharged by a licensed ARCtick technician (AU/NZ requirement).
• Replace the receiver–drier any time the system is opened, and especially after a compressor or TX valve change.
• Use new HNBR O‑rings lubricated with the correct refrigerant oil, match oil type/quantity to the system. If there’s been a compressor failure, request a thorough flush.
• After fitting, evacuate to deep vacuum, hold, then recharge to the exact mass on the under‑bonnet label (R134a for this model year).
• Keep the cabin filter fresh and the condenser clean, low airflow can mimic TX valve issues.

Access on the Mondeo is at the firewall where the two A/C hard lines enter the cabin. The valve is clamped to the evaporator block. Corrosion at the fittings and aged O‑rings are typical leak points with age, so a careful clean, proper torque, and leak-test with nitrogen and dye/UV check are worth the extra minutes.

FAQs

Where is the TX valve on a 2001 Mondeo?
It’s mounted at the firewall on the evaporator, where the two A/C hard lines meet. Access is from the engine bay at the bulkhead, some trims may need the cowl area cleared for room.

Does the 2001 Mondeo run R134a and a receiver–drier?
Yes, it uses R134a. The system is a TXV/receiver–drier layout, and the drier should be replaced whenever the system is opened to air or after major component work.

How do I tell if it’s low gas or a crook TX valve?
Low refrigerant usually shows weak cooling across all conditions and visible oily residue at a leak point. A failing TX valve more often causes fluctuating vent temps, frost right at the valve, or odd pressure readings that don’t improve after a correct recharge.