Mini split Freon possible over charge

[priobe]

Hello
I did an install of a mini split 1.5 ton. The line set was 25 ft and the unit was suppose to be charged from the factory for 25 ft. I noticed my evaporator was icing up, and check the pressures and noticed it was at 60 PSI. Called the company and they said it should be 130 psi.
I charge the unit with bottle upside down and it is over at 134. I tried releasing some gas, and then some more gas, but the pressure does not seem to lower.

I don’t want to release anymore until I know what’s going on.
And thoughts ?

 

[BKB]

Not a pro but I’ll bite. So do you have a leak? Was the unit properly installed with line set pulled down below 500 micron? Does your unit have a test button or some way to put the compressor at 100% so you can do superheat? Im going to guess no or you have no idea to any of these questions. I will also assume this is 410a. Soap and water your connections if all looks good I would recover the system, pull vacuum and weigh in the proper amount of refrigerant. To me it’s the only correct way to deal with these inverter type systems.

 

[priobe]

The system is a 410a. This is a diy and manufacture said the system was probably was shipped with low Freon. No leaks were detected and the system was pulled down to 500 micron. Manufacture indicated I should run system at low temp and add Freon slowly to 130 psi.
Those were the instructions.
Not a pro but a Diyer. System blows cold and working fine just concern about pressure.

Thx

 

[acmikee]

first change your post and remove the part where you admit to venting refrigerant that is illegal.
what is your delta T i wouldn't worry to much about it @134psig to properly charge it you need to recover the system and weigh in the charge

 

[priobe]

Acmikee I never said I released it to the atmosphere, that would be illegal as you mentioned.

Thx

 

[justinjoyal]

DIYers sure have changed. None would have had a refrigerant recovery machine nearby back in the days.. ! [emoji849]

What are the indoor/outdoor temperatures when you are running that 134psi pressure ?

 

[priobe]

Indoor temp. = 77
Out door temp. 81

 

[justinjoyal]

Seems alright.... air temp at discharge ?

 

[LS6 Tommy]

Acmikee I never said I released it to the atmosphere, that would be illegal as you mentioned.

Thx

Letting refrigerant into the atmosphere is exactly what the term "release" means... You recovered the refrigerant.

And yes, a full recovery, leak check, evacuation and weighed charge is the proper repair.

Tommy

 

[LS6 Tommy]

DIYers sure have changed. None would have had a refrigerant recovery machine nearby back in the days.. ! [emoji849]

What are the indoor/outdoor temperatures when you are running that 134psi pressure ?

Indoor temp. = 77
Out door temp. 81

Seems alright.... air temp at discharge ?

Those numbers are not that closely related. What are the indoor air return and supply temps? You should be seeing around a 20° F Delta.

Tommy

 

[justinjoyal]

Those numbers are not that closely related. What are the indoor air return and supply temps? You should be seeing around a 20° F Delta.

Tommy

Working with minis year 'round you get to know if a simple pressure measurement makes sense depending on indoor/outdoor temp. Just a start you know.

 

[theoldwizard1]

Call a pro who has recovery equipment, a proper vacuum pump and proper gauges.

DO IT RIGHT !

 

[BD1]

You probably added Freon on the suction side, low side. With tank inverted, you dumped in liquid instead of gas. It can be done but usually you would invert momentarily and then turn tank upright.
Dumping in liquid on low side can slug compressor. It will take time for system to equalize.
Remember, pressure is affected by temperature. The hotter it is outside, the pressure increases.
There should be a temperature / pressure chart in manual.
This is what is used to add liquid on suction side.

https://www.amazon.com/gp/aw/d/B004RIDG02/ref=ox_sc_saved_image_9?smid=A22WTOHBJCDJMP&psc=1


Sent from my iPhone using Tapatalk

 

[justinjoyal]

You probably added Freon on the suction side, low side. With tank inverted, you dumped in liquid instead of gas. It can be done but usually you would invert momentarily and then turn tank upright.
Dumping in liquid on low side can slug compressor. It will take time for system to equalize.
Remember, pressure is affected by temperature. The hotter it is outside, the pressure increases.
There should be a temperature / pressure chart in manual.
This is what is used to add liquid on suction side.

https://www.amazon.com/gp/aw/d/B004RIDG02/ref=ox_sc_saved_image_9?smid=A22WTOHBJCDJMP&psc=1


Sent from my iPhone using Tapatalk

I'll be honest, we never used that and I never saw it being used...

 

[priobe]

BD1, yes it was added on suction side but everywhere I looked said to add with the bottle inverted.

 

[LS6 Tommy]

You probably added Freon on the suction side, low side. With tank inverted, you dumped in liquid instead of gas. It can be done but usually you would invert momentarily and then turn tank upright.
Dumping in liquid on low side can slug compressor. It will take time for system to equalize.
Remember, pressure is affected by temperature. The hotter it is outside, the pressure increases.
There should be a temperature / pressure chart in manual.
This is what is used to add liquid on suction side.

https://www.amazon.com/gp/aw/d/B004RIDG02/ref=ox_sc_saved_image_9?smid=A22WTOHBJCDJMP&psc=1


Sent from my iPhone using Tapatalk

You have to remove 410a from the can as a liquid. It's a blend, so you can't pull it out of the can as a vapor. As long as you do it slow enough, it will vaporize in the suction line and not slug.

Tommy