Holding Vacuum When Evacuating, How Long??

[philipswanson]

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?

[tbirdtbird]

We don't prefer dye here. Sniffer never lets us down. That long wand enables you to get it just about anywhere/everywhere.
In fact have never used dye, to us it fell by the wayside once the price of sniffers came down

[Tim]

Lots of oil companies place a dye in the oil. It won't hurt anything, but I would not use it as the main source for leak detection.

[philipswanson]

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 don't know how to interpret these random beeps here and there???? Any tips on how to use it?

[Tim]

I have trouble use 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 don't know how to interpret these random beeps here and there???? Any tips on how to use it?

What brand of leak detector/model is it? There are junk options on the market and everyone wants to save a buck these days.

[tbirdtbird]

Agree. We have a TIFF, and it has a sensitivity setting. A quality brand is not tricky to use.
If something from Horrible Fright, then all bets are off

A tool that does not do its job is the most expensive of all of them

[philipswanson]

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

[Tim]

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

I never used the tek-mate, but they are known to be good.

[tbirdtbird]

Just looked at Inficon model 705-202-G1 online. Looks like it has hi and lo settings. Use hi to get a gross idea that a leak does exist, then zoom in on low to pinpoint.
Refrigerant can linger, and it is heavier than air. So it is easy to get false readings. Readings must be reproducible else there is no leak.
Be sure caps are on the ports, they finish the job of sealing.
I can remove the caps from most any car and sniff and get a leak.
I have "fixed" leaks by simply installing caps where the last guy didn't bother to reinstall it, and it got lost

[philipswanson]

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 a new one for free from the manufacturer. I suppose both methods have their purpose.