What is the current way to recharge a R410A system with a broken line set.

Wayne_16

What is the current training /requirements to properly service a R-410A system that has lost the charge due to a line breaking during the winter.  This is a new heat pump system that had the condenser base tip, and break the line due to the ground shifting this fall.



Specifically I want to know the best way to treat this system for air, non condensables etc that I may be dealing with.  I know the R-410A refrigerant likes to absorb water etc when open to the enviroment. The line may have been cracked for up to 3 weeks this winter.  Snow and rain occurred during the time.  The line has been repaired to keep any additional moisture etc from entering the system.  What I want to know is what are the manufacturers stating is the best way to deal with a field problem. 



Thank you,

Minnesota Wayne

Unknown

HVAC Inside sales

The best thing to do is to buy a line set cleaning charge usually a one time use item found at a lot of wholesalers and refrigeration sales companies. Then use nitrogen to scrub the line further, followed by a vaccum and a Micron gauge run down to 500 Micros to remove any remaining impurities. Then if there is any charge left in the condenser it will have to be reclaimed. Then fully recharg the condenser by weighing it in according to the chart on the unit that it was charged with when it left the factory. Any other way of charging will cause problems as R410A is a blend and needs to be charged in properly. 

Tom Blackwell_2

System Cleaning

The system will need a good cleaning before evacuation. The oil that resides in all surfaces exposed to refrigerant will hold moisture in the form of an emulsion, and must be thoroughly removed. Recently, I have used denatured alcohol, blown through with carbon dioxide. There may be a better solvent, somebody else chime in. After this process, evacuate to at least 500 microns and see if that vacuum level holds. If not, there is still moisture somewhere in the system. Wouldn't hurt to install a suction filter also.

Wayne_16

Thanks for the replys,

I know and have used the nitrogen charge before, was not aware of the cleaning solution and will check into the availability etc.  In a freezing environment the vacuum pump will have little to no effect to remove the moisture?  Am I right or missing something,  I know water will boil at room temperature, but will effect will a good vacuum pump with clean oil have on a system when the outside temperature is below freezing?  Right now -8 F and barely made it to the plus side of zero this week so far.  Next week looks, better, mid twenties for highs.



Thanks,

Minnesota Wayne

Jaz

Pumping in cold

Wayne,

I also am in MN. You are right about the pump working in the temps we are having right now even if you would keep the pump warm before trying to evacuate that system. Since this is a heat pump right now it wouldn't be very efficient to run if it ran at all. So is it possibile to hold off on trying to get it repiped and pumped down like in February when temps might start coming back up. The cleaning solution might be found at united refrigeration in Bloomington.



Wholesale

Jaz

Eugene Silberstein 3

System Cleanup

As was mentioned by others, the POE oil used on R-410A systems is very hygroscopic, meaning it just loves moisture!

Depending on how bad things are with the system, you might very well consider replacing the oil in addition to cleaning out the lines. One thing is an ansolute must.... Install suction line and liquid line filter driers and be sure to replace them both after a few days of operation.

Please keep us posted with your progress!!

Best of luck to you!

The Professor