Thanks will try again tomorrow. I hope it's not the evaporator because those lines in the back are a real PITA! Once before I had evaporator trouble in this coach and was impressed by the dye method because you could see all the individual pin hole leaks in the coils. That feature enabled me to get ...

It is a Inficon Tek-Mate. It is not a cheap one from Harbor Freight.

I have trouble using the sniffer because it beeps all over the place. I put it behind the evaporator and it beeps once or twice, then stops. I move it around and it beeps but not consistently in the same place. I don't know what it's telling me. I have resorted to using dye and a mirror because I do...

I have a sniffer but do you ever combine this with dye since many suspected areas are hard to reach with a sniffer. Aren't the dyes even better to spot pin hole leaks?

Doesn't the dry nitrogen mix dilute the effectiveness of the sniffer?

OK, can you tell me the best method for doing the leak test? Thanks.

When evacuating the system in a motorhome, how long should it be able to hold vacuum? Mine dropped a little overnight. Does that mean I have a leak? It held steady for a few hours when I started.

Tim,
Did you post this yet. Many would like to see it I'm sure.

One thing I know is that many valve cores are damaged during servicing because the service valves are tightened down way too much. I try not to bottom them out all the way. I still have leaks there though.

Also. whenever I have used cans, they don't empty. That's why California has a deposit on the cans for return and catching unused R134. The cans sold there have a special adapter that holds that excess R134 in. Only about 3/4 of the can even gets into the system. It's a big waste compared to a bottle.