Parts for your 2022 Mazda 3-Tx valve

2022 Mazda 3 TX‑Valve: what it does, and when to service it

Yes, the 2022 Mazda 3 is fitted with a TX‑valve (thermostatic expansion valve). This isn’t guesswork: Mazda’s BP‑series workshop manual includes “Expansion Valve Removal/Installation” under the HVAC section, and the Mazda Electronic Parts Catalogue for the BP chassis lists a “Valve, Expansion” as part of the evaporator assembly. DENSO’s HVAC technical literature also explains the TX‑valve’s role in modulating refrigerant flow to the evaporator, which matches the Mazda 3’s air‑con layout.

On this Mazda, the TX‑valve meters liquid refrigerant into the evaporator based on outlet temperature and pressure, keeping the evaporator cool without letting it freeze. It helps deliver steady, quick cabin cool‑down and good demist performance, especially in sticky Aussie or Kiwi summers. Because it balances flow against load, it also helps the compressor work efficiently.

It’s a sealed, long‑life component with no routine maintenance interval. Still, if the system’s been contaminated (moisture, debris after a compressor failure) or the valve sticks, owners might notice the following:

• Poor cooling at idle but better at speed, or the reverse
• Evaporator icing, intermittent vent temps, or hissing at the firewall
• High or unstable high‑side/low‑side pressures on gauges

If replacement is needed, it’s a straight mechanical swap but strictly a job for a licensed air‑con technician (ARCtick in Australia, approved handlers in New Zealand). They’ll legally recover the refrigerant, replace the TX‑valve and O‑rings, add the correct PAG oil amount if required, evacuate, leak‑test, and then recharge by weight with the specified refrigerant (R‑1234yf on most late‑model cars, though some markets may still use R‑134a—always check the under‑bonnet label). Whenever the system is opened, a new receiver‑drier/desiccant should go in to protect the fresh valve and the compressor.

DIY checks that help before booking it in: make sure the cabin filter is clean, the condenser isn’t blocked with bugs, and both radiator fans run with the A/C on. These simple things can mimic TX‑valve issues. As for access, the Mazda 3’s TX‑valve is mounted at the evaporator on the firewall, depending on tooling and model specifics, access can be tight, so expect a bit of labour time.

Bottom line: the TX‑valve on a 2022 Mazda 3 is there for precise cooling control and compressor efficiency. It doesn’t need regular servicing, but when symptoms point to it, proper diagnosis and licensed replacement protect the rest of the A/C system and keep the cabin frosty.

Popular questions about the 2022 Mazda 3 TX‑valve

Does the 2022 Mazda 3 definitely have a TX‑valve, not an orifice tube?
Yes. Mazda’s BP‑series workshop procedures and the Mazda EPC list an expansion (TX) valve at the evaporator for the 2019–2023 Mazda 3. That’s the standard control device on this platform rather than a fixed orifice tube.

How often should the TX‑valve be replaced on a Mazda 3?
There’s no scheduled interval. It’s replaced on condition—typically if it sticks, clogs after a compressor failure, or testing shows abnormal pressures/temperatures. Any time it’s replaced, the system should be evacuated, recharged by weight, and the receiver‑drier renewed.

Can a bad TX‑valve damage the compressor?
It can contribute. A stuck‑closed valve starves the evaporator and may lead to poor oil return, while a stuck‑open valve can flood the evaporator and upset system balance. Left unchecked, either condition can stress the compressor, so prompt diagnosis is smart.