Re-charge heat pump R410a

[cypher_171]

Hello all,

I have a R410a split system heat pump that requires a full recharge, the service valve is on the LP Vapor Side. I know that R410a has to be charged in its liquid state to maintain the blend but im cautious of possible damage to the compressor, I intend to add refrigerant slowly throttling the valve to vaporise the liquid in the lines. I dont have to hand an atomiser/safety charger, can anyone who has had experience with these systems share there methods also the system charge is 1.5Kg is there a recommended point when i should envoke the compressor?

Your help is greatly appreciated!

[paul_h]

Evacuate the system, then liquid charge through the suction port when the system isn't running. When the system is in a vacuum, I have no problem getting 3.5kg into these systems.
Wait 5-10 min before running the compressor.

[wineman]

vac it out bomb charge it and weigh the charge in then let the liquid boil off and hey presto

[BigJon3475]

Did the system run in a vacuum? If so you may need to do some more work than just recharge or else you get the green slime if to much moisture entered the system while it was pumping in a vacuumor pumping straight atmospheric air through the system. If you know how long it ran without refrigerant that would be a big help also.

[The MG Pony]

BigJon brings in a good point! If you suspect it ever ran in a vac I'd toss ina good big Filter dryer to ensure a good dry system.

[BigJon3475]

Filter dryer always goes in with 410a if the system is opened. I was referring to the poe oil absorbing moisture. You may need to change out the oil and then install a filter dryer just to be safe. If there is enough moisture in the system you can charge it correctly and come back later and the moisture in the system will start to turn the oil and ref. into a green sludge. You have some room to play but if this thing ran for a week like this I would change the oil and start over fresh with dryers and virgin ref.