Rheem/Weatherking factory over charged.

[kenadiens]

Anyone have this happen to them. New install and the head pressure was bouncing around and ended up 475 vapour pres. was 115. These readings are in heat mode. 50 F OT. 65 RAT. subcooling was through the roof. My first thought was non condensables. So I return the next day with all the gear to recover and redo but got to thinking this is nuts. I installed and know that I Pulled it down to 475 microns and it held tight. So I decided to recover a pound of refrigerant and see what happened. Bingo! Had to pull out another 8 oz. and the numbers were beautiful. Boy was that a frustrating one.

[slctech]

It happens...mostly been seeing it on rooftop units. There are bulletins out on York equipment with the Micro-Channel cond coils, that certain models were overcharged at factory, had a bunch of those last year.

Was your system a split system? May have factory over-charge, but on split systems I plan on removing or adding charge as needed upon install. It is on packaged equipment that I get frustrated with when they are over or under charged by the factory. PIA to verify and get labor and reimbursement under warranty.

[kenadiens]

It was a split system and Rheem will definately be getting a bill. I haven't seen it yet on a package unit.

[George Fernandez]

How long were the lines? Aren't most systems charged for the condenser, evaporator and 15 feet of line-set? Matched system. i.e. 2 ton AHU and 2 ton condenser.

[kenadiens]

Ya it is charged for 15 feet. The line with 90's added was 17 feet.

[Mille Racer 69]

I cant tell you how many Goodman's I've seen with an improper charge.
Even had a few units supposidly charged still charged with nitrogen.

[kenadiens]

now there would be a surprise.

[gravity]

ive seen alot of overcharged units from the factory. with a rheem im wondering if airflow wasnt your real problem and you covered it up by removing refrigerant

[kenadiens]

No. My first thought was non condensables but not having my recovery tank or a new filter I figured I'de double check the other options and Air flow was number 2 on my list. It was smack on and I even adjusted the dip switches to increase it 10 % and it didn't do any good.

[meh70087]

What exactly is "smack on" in reference to air flow?

[kenadiens]

3 ton system. cfm came to 1250.

[Baycienda]

I've never seen a system that I felt the factory charge was over or under charged. It always comes out close to spec, but then again I can't be positive about that. Factories have very specific guidelines they go through before a system goes out the door. I was told one day by a tech that factories charge condensers by time, not by weight. So, say for example, if you have a cylinder that was full, the system would charge at a much faster rate than a cylinder that was near empty. I would think that a factory would no they need to charge by actual weight. I can't see a factory actually putting out a condenser with nitrogen in it without specifying it is a dry unit. I would say that install error has a lot to play with these situations.

[Willserve]

I know Rheem had problems in the past with overcharged heat pump units. They worked fine in cooling mode but kept kicking out on high pressure in heating mode. Look at the size difference of the condenser and evap coil in a rheem heat pump. I had this problem on a 12 Seer Rheem I installed for myself several years ago. It kept kicking out on high head, checked air flow, coil, duct (all new) etc. Then finally took about a pound out and it's worked perfect ever since. I have removed freon on several Rheem and Ruud heat pumps, some I installed some I didn't. Usually if it kicks out on high head in heat mode and coil/filter are clean it's overcharged.