A/C not turning on

[mini_fd]

I just installed a condensor and a compressor this evening and was succesful creating a vacuum seal. It held its pressure at 26 microns and didn't drop one bit. I put everything back together and when I go to turn on the a/c after putting freon in the system, it didn't click on. The green light turns on but the clutch doesn't engage.

I just got this part from partsgroup and it has 27k miles on it. Tom says that it worked fine when he took it off a '00.

What didn't I do correctly for the a/c not to turn on? The fuse in the cabin isn't blown either.

[Boris]

How did you charge the system ?
A low pressure switch will keep the clutch from kicking in.

[mini_fd]

a can of freon on the cold side with the ac blasting on 4. The light comes on but it does kick in. and tell me more about the low pressure switch.

Is my problem electrical?

[Boris]

I don't know how much refrigerant the Miata takes but one small can might not be enough.
There should be a sticker under the hood with those details.

Flip that can upside down and dump some liquid in there. See if that gets the clutch to kick in.

[mini_fd]

I have a big can. I will try the entire can this time.

[mini_fd]

got it to click on!! I feel like an idiot. I was being to cautious. It took just about the entire big can I got from autozone. The one that has the faux cf paper wrap on it.

[chiefmg]

In order to charge an modern A/C system properly you need to go by the weight of the charge. If not you could have an over- or under-charged system.

[Boris]

Yep, you should weigh in the charge.
I'm guessing you won't so at least don't overcharge it.

[mini_fd]

Thank you guys. I received replies and help faster then two other forums I use.

[joe morreale]

If I charge my ac to the miata spec of 13 oz. it just doesn't get cold. I have gone to the were is it blowing cold without interrupting the way the engine runs method. To much freon (134) and it won't idle right. Yeah, I know, ghetto, but I got cold air.

[mini_fd]

In order to charge an modern A/C system properly you need to go by the weight of the charge. If not you could have an over- or under-charged system.

I went to a shop today to extract out the freon I had put in and anything else left over in the system. They squirted some oil in the system and then 1.3 lbs of Freon. I feel much better that I got it done all for 83 dollars. Oh and they also spotted the valve on the cold side spitting tiny bits of freon once the cap was twisted off. Good thing they took care of that as well because I would have never knew I had a leak once the screw cap was taken off.

[— Agent☣Orange —]

Where did you get it done?