Most commonly a low charge is the cause of a frozen evap but there could be other issues. You can google a temperature pressure chart for the refrigerant you are using. I don’t do residential but I work on refrigeration. Always check airflow first. Nice clean coils. Then fan operation. Check for drain obstructions if all that is good and compressor is running then it’s on the refrigeration side. Put gauges on as a last resort. Also it’s good to see the high side as well. If you have a restriction, you could be overcharging by adding refrigerant. Gauges on the high press side would show you that. If you know u have a slow leaker then it’s probably fine topping it off like you did.
problem is ive bin doing this for 10 years on this system never needed to bother the high side. its a total waste of time and only needed if a refil doesnt work . 99.99999 % of the time you are simply low on refrigerant due to a shrader valve .
Thanks for the input good buddy im not nocking you its just that after hooking up the high side every year for no reason gets old and it waste refrigerant and supposedly destroys the planet letting out those burps so from now on we only do the high side if a problems Persist .
You would dial it in better hooking up the high side to check your superheat Low side check your sub cooling . 1.) Valve off tank afterwards 2.) Crack the high side gas gauge then low side and pull that little bit into the system .
You have a leak if you have to recharge. Most likely it's the valve cores on those service ports. Put some 1/4 inch brass flare caps with copper gaskets on those ports to prevent leakage.
