Parts for your 2019 Mazda Cx-5-Tx valve

2019 Mazda CX-5 TX Valve: What It Does, and When to Service It

Based on technical documentation, the 2019 Mazda CX-5 (KF series) is fitted with a thermostatic expansion valve (TX valve, often an H-valve) mounted at the evaporator inlet. This is confirmed by Mazda’s Workshop Manual for CX-5 KF (A/C Expansion Valve Removal/Installation), Mazda Genuine Parts Catalogue listings for “VALVE, EXPANSION” on 2017–2021 CX-5 applications, and OE supplier application guides (e.g., DENSO A/C catalogues for CX-5 KF). So, yes—the TX valve is relevant and used on the 2019 CX-5.

The TX valve meters liquid refrigerant into the evaporator based on temperature and pressure, keeping superheat in the sweet spot so the evaporator doesn’t flood or starve. That steady control means quick cool-downs, stable cabin temps, less compressor stress, and better efficiency—especially important on R-1234yf systems used in many CX-5 markets.

As a rule, the TX valve isn’t a scheduled-replacement item. It’s serviced or replaced if there are performance dramas or contamination after a component failure. Typical clues that point to a crook TX valve include:

• Weak or uneven cooling, especially at idle or in traffic
• Frosting or sweating on the evaporator inlet/outlet pipes
• Erratic high/low-side pressures during gauge testing
• Audible hissing at the dash that doesn’t settle with fan speed

When replacement is required, proper A/C procedure matters. The refrigerant must be safely recovered, the system opened, O-rings replaced and lightly lubricated with the correct PAG oil, then the new valve torqued to spec. Because the CX-5’s desiccant is integrated in the condenser assembly on many variants, Mazda procedures typically call for desiccant bag or condenser replacement if the system’s been open or contaminated. A thorough nitrogen pressure test, deep vacuum, and an accurate recharge by weight are non-negotiable for best results. It’s also smart to renew the cabin filter and treat the evaporator for odours while the system’s being sorted.

Annual A/C performance checks are a good habit—verifying vent temps, condenser cleanliness, and leak-free operation. Any refrigerant work in Australia should be carried out by an ARCtick-licensed technician, and in New Zealand by a suitably licensed refrigeration/air-con professional. That keeps the CX-5 cooling crisply through long summer drives and stop–start city crawls alike.

Popular questions about 2019 Mazda CX-5 TX valves

Does the 2019 Mazda CX-5 use a TX valve or an orifice tube?
The 2019 CX-5 uses a thermostatic expansion valve at the evaporator, not a fixed orifice tube. Mazda’s KF workshop procedures and parts listings identify an expansion valve specifically for this model range.

How much does it cost to replace a TX valve on a 2019 CX-5?
Costs vary with labour time, refrigerant type (R-1234yf is pricier), and whether the desiccant/condenser is renewed. As a ballpark, owners commonly see 1.5–3.0 hours labour plus parts and gas, often landing in the AUD/NZD $350–$900 range. Diagnosis first is wise, as similar symptoms can also point to a weak compressor or blocked condenser.

Can a TX valve be cleaned or adjusted instead of replaced?
TX valves are calibrated components and generally not serviceable. If stuck, restricted, or internally contaminated, replacement is the reliable fix. After any internal A/C failure, expect to address the desiccant and flush lines as per Mazda procedure to protect the new valve and compressor.