1 1/2 years old 5 tons leaking yellow rusty water

If the unit is running in cold weather than there is ice building up on the coils located outside. This is normal in that the unit is running in heat pump mode heating inside and cooling outside, After the unit detects the ice build up it briefly reverses the cycle heating the outside coils melting(defrosting) the ice which you observe as water on the pad.

The video gives you an example of the defrost cycle!
2012 Trane XL15i Heat Pump Defrost Cycle Steam Show

Water heaters are sealed tanks. The only places where water would normally be able to leak would be:

1. Water inlet
2. Water Outlet
3. Heating elements
4. pressure release valve
5. drain valve

Leaking at the base is indicative of a rusted-out tank. But before you trash the old one, secure power and remove the side covers where the heating elements are installed to verify they are not leaking. If they are OK, the unit probably needs replacing. And even more likely if the unit is more than 10-12 years old. Don't delay on this as leaks from rusty tanks can blow out and cause serious water damage,

You say 2 to 3 years... I'm assuming the unit is older than that. Especially being r22. What about the first 10 years??? Normally you will get 400 to 500 sqft per ton of cooling, but, that depends on heat load calculations. If the unit wasn't big enough you would have had this issue 10 years ago, not when the system kept running low on refrigerant. At first guess I would say a 2 ton unit is not big enough but if it worked fine for 10 years...wuth all that in mind, if it were me, (a seasoned professional) I would spend 1800 to fix my 15 year old r22 unit before I spent $4000 on a new r410a piece of junk. Best Wishes!!

If you need further help, reach me via phone at https://www.6ya.com/expert/thomas_092728000e6acb79

Nothing will remove the buildup because that is mostly the housing of the unit distorting over time with the chlorine inside. Puck quality has a bigger effect on water chemistry than the chlorinator itself though cheap imported pucks are likely to stain the inside of the chlorinator just like they often do to the pool. A new inline chlorinator is about $90 so I would assume it is better to buy a new one than to try and repair a worn out 20 year old one...just my opinion.

John

Ensure the black "duckbill" gasket is mounted on the bottom of the dirty water tank. This gasket is removeable, and resembles a duck bill.

When i purchased mine at Target, new - it was missing the gasket, causing loss of suction. Interestingly it worked for a week or 2 then started leaking. Now, with the gasket in place, it works like a charm.

Gasket is about 2 bucks available from Bissell.

are you storage chemicals next to the heater or you may have a leak from the pool that is your rust

Epoxy wont hold you need a new coil. about 8 to 12 hundred depending on your location. If it is 10 years old I would suggest you change the air handler. You will get a lot more efficient unit. Cost about 2200 but you will get a 10 year warranty from most manufacturers. Dont buy one unless you get a 10 year warranty. Russ

Gas has leaked from inner or outer unit kindly get it checked by service men they will find the leak and charge the gas again normally after some time it gets rusty inside as water is involved and got leak

no problem get it repaired not expensive

pls rate me well !
Regards

faulty, replace it because that leak has damaged the tank inside it must all rusty and will give up soon