Automotive Air Conditioning Information Forum

I bought a Harbor Freight sniffer. On its default setting, it goes from 'beep beep beep' to 'siren' when I check the service ports. These fittings are new. Is this a common problem? With the plastic cap on, I don't get an indication of a leak on the default setting, but when I take the caps off, I do. All of this is with the engine cold, I charged the system a couple of days ago.

Is there a specific protocol for testing these valves?

And if they need replacing, do the DIY tools work or do I need to go to a shop where they can recover the refrigerant, replace the valves and recharge?

msrichmond wrote: ↑Tue Jul 16, 2024 11:35 am With the plastic cap on, I don't get an indication of a leak on the default setting, but when I take the caps off, I do. All of this is with the engine cold, I charged the system a couple of days ago.

Perfect !!!! The cap is the real seal, the schraeders are not the primary seal !!!

msrichmond wrote: ↑Tue Jul 16, 2024 11:35 am And if they need replacing, do the DIY tools work or do I need to go to a shop where they can recover the refrigerant, replace the valves and recharge?

From what I've read: the special tools do work. Watch the videos on YouTube. But you have no need right now for this !!!

That is how I test my leak detector- take off the caps and make sure it works...Then put caps back on.

Thank you!