FSM wants me to recharge AC, dump it, then refill again? That doesn't seem right

[Backpacker]

For the 1989 model year. Has anyone followed the FSM instructions for servicing the air conditioning? It says to fill form high side, vacuum it out then fill again from high side them fill from low side after that. All this with the engine off. I thought you should only fill from the low side with the compressor running?

 

 

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[adamzan]

That makes no sense and I would just do it the "normal" way.

[Citron]

The FSM is giving the procedure for flushing the system, which requires the correct machines to vacuum the system and recover all of the refrigerant.

 

You are just trying to recharge it correct? If so, then yes, low side with compressor running.

[Jester93]

Was the system opened up? Difficult to direct if I don't know where your coming from.

[vagabond]

if the system wasn't open and your just topping off, top it off thru the suction side. watch the sight glass on the reciever dryer

and stop filling when it clears up when it's low it will look like soap bubbles when it's full it will be clear, looks almost the same

when it is completely empty. DO NOT OVERCHARGE

[KovemaN]

Quick follow up:

 

Dead/No pressure: Vacuum, wait (a couple of hours), confirm vacuum, charge on the LOW side with the recommended amount of refrigerant. (A flush is recommended if replacing a component).

 

Some pressure and unknown leak: Pressurize on the low side. Find a chart for pressure vs/temp and fill to correct pressure based on temp.

 

Use dye only if you know you have a leak and know what to look for. Don't use sealant or most shops won't touch it. If you did use sealant, don't tell them.