InstallerSHOW 2026 Giveaway Day 2

Terms and Conditions Apply.

Working on refrigeration and air conditioning systems has never been easier.

The testo 558s combines maximum precision and maximum flexibility in operation with ease of use therefore it is setting new standards for all applications involving refrigeration, air conditioning and heat pump systems.

Touchscreen and clear visualisation of readings.
Connection to the testo Smart App for easy documentation and fast sending of measurement reports
Protection class IP 54
Compatible with flammable A3 and A2L refrigerants
Readings recorded up to 30min as trend curves. Optionally extendable up to 72h.
High precision of 0.25 % fs over the entire measuring range (60 bar), including integrated temperature compensation