It looks like 3 1/2t by the numbers on it,I'd like to see model number off of outside condensing unit also to be sure though.
That bump is usually caused by the pipe rotting from inside out.
I'd screw it on to an outside faucet and open the valve to see what you have for pressure.
Anything much over 70psi will cause problems with pop...
Check those roto loc fittings on the outside unit,shrader valves are also a common leaking point.
Do you have the model number off of outside unit so we can make sure of size coil you need?
Biggest thing is to get a coil sized for the tonnage...
Looks like there's a rock between the pad and condensing unit in your picture.
Fresh meat boys,long time contractor.
Mostly in the Electrical/Hvac and plumbing trades.
But have done other things when needed to get the job done.
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