Parts for your 2018 Haval H6-Tx valve

2018 Haval H6 and the TX‑valve: what it is, where it lives, and how to look after it

Based on Haval’s service literature for the H6 HVAC system, the Haval electronic parts catalogue (EPC), and common aftermarket catalogues from major A/C suppliers that list a block‑type expansion valve for the 2017–2019 H6, the 2018 Haval H6 is fitted with a thermostatic expansion valve (TX‑valve) at the evaporator inlet. This layout pairs a TX‑valve with a receiver–drier (typically integrated with the condenser) rather than an orifice‑tube/accumulator setup.

On the 2018 H6, the TX‑valve meters liquid refrigerant into the evaporator, reacting to bulb or internal sensor feedback to keep the evaporator just shy of freezing while maximising heat transfer. In plain speak, it’s the brainy tap that keeps cabin temps steady on stinking‑hot days without icing the core. Because it constantly balances superheat, a healthy TX‑valve helps deliver quick pull‑down at idle and stable vent temps on the highway.

As part of routine A/C servicing, there isn’t a “clean and refit” option for the TX‑valve—it's a precision valve. What owners and workshops can do is keep the system dry, clean and correctly charged so the valve stays happy. Any time the system’s opened, moisture control matters: the receiver–drier should be renewed to protect the TX‑valve from acid and debris. Always confirm the refrigerant type on the under‑bonnet label (many H6s use R‑134a, some markets moved to R‑1234yf) and recharge to the specified weight.

Typical clues the H6’s TX‑valve is struggling include:

• Vent temps that swing hot–cold, or poor cooling at idle but better on the move
• Frosting at the evaporator/valve or a hissing, hunting sound behind the dash
• Pressure readings that show starved evaporator (low suction) or flooding (high suction)

Replacement is a workshop job requiring refrigerant recovery, so an ARCtick‑licensed tech in Australia or a suitably certified technician in New Zealand should handle it. The process is: recover refrigerant, remove the glovebox/evaporator access, unbolt the block‑type TX‑valve, swap O‑rings (lightly lubricated with the correct oil), fit the new valve to the specified torque, evacuate to deep vacuum, and recharge by weight. If contamination is suspected, add a new condenser/drier (given the integrated drier design) and a high‑quality cabin filter to keep airflow optimal. A quick UV dye check and a post‑charge performance test round out a proper job.

Look after the basics—clean condenser fins, correct charge, dry system—and the H6’s TX‑valve will usually run for years without a fuss.

Popular questions

Where is the TX‑valve on a 2018 Haval H6?
It’s a block‑type valve mounted at the evaporator inlet, behind the dash on the passenger side. Access typically involves removing the glovebox and trim to reach the HVAC case.

What are the signs the TX‑valve is failing on a H6?
Expect unstable vent temperatures, weak cooling at idle, frost or sweat on the valve/lines, and A/C gauges showing abnormal high/low side behaviour. A proper diagnosis with thermometers and manifold gauges is best.

Do I need to replace the drier when changing the TX‑valve?
Yes—if the system has been opened or contamination is suspected. On the H6 the drier is typically integrated with the condenser, so the condenser assembly is replaced to renew the drier.