Mini-Split Charging help please

I bought and installed a pioneer mini-split system. I got everything up and charged, the thing cooled the tent down in just a few minutes. It was awesome, until it stopped cooling as good. I found and fixed a leak on one of the fittings but now I need to recharge the system.

I know I need to vacuum down the system, but here's my question. When I first installed it, the service ports on the hi and low side were closed off when I pulled down the lineset. I then opened up the service ports to release the precharged freon into the system. Now that I have to recover and add new freon into the system, do I shut off the service ports or leave them open during vacuum?

Thank you for any help!

You would leave the ports open. You probably dont have any freon to recover. Vacuum in the system will allow moisture to boil at low temps. Most professionals will vacuum the system then purge the lines with Nitrogen gas...
This makes me nervous because I had my eye on Pioneer mini splits... I heard of others that have had problems with the quick connect fittings, are they really that bad?
Before you released the freon in the system you were supposed to vacuum the lines and perform a leak test. If it can hold a vacuum, it can hold pressure! Most professionals will put a vacuum on the system and come back 24hrs later and see if it holds. Then, you release the freon... I think you void the warranty if you dont have a HVAC guy with a license#.
I am not trying to make you feel bad or anything, I was probably going to set up my own system. However, I have friends that have a valid Hvac license#. For the warranty, there usually has to be an invoice # proving that you hired a company...

I think that you can rent a vacuum pump. It is pretty important to get the moisture out of the system! Your compressor will not last long with moisture...
As far as rentals go, I think that you can get everything but freon. Maybe??? You can find used ones on craigslist for under $200. You could just resale it when you are done!

I am going to be asking you plenty of questions. I started a Pioneer thread but it is dead. Not one reply. You are the only person that I have been able to talk to that owns a system...

Where the lines really cheap and shitty??? Faulty/missing pieces for the line set is the only negative review that I have seen about the system.
Experts will cut the flared fitting and braze the copper lines together.
You need to wake up and talk to me lol. The only reason that I have not bought this system is because they are on back-order until May18th.! I really want to know if it was faulty equipment or do you think that you messed up during install? I have seen one person talk about a missing copper gasket for the quick fitting. It cost him .50cents from Grainger.

MustangStudFarm said:

You would leave the ports open. You probably dont have any freon to recover. Vacuum in the system will allow moisture to boil at low temps. Most professionals will vacuum the system then purge the lines with Nitrogen gas...
This makes me nervous because I had my eye on Pioneer mini splits... I heard of others that have had problems with the quick connect fittings, are they really that bad?
Before you released the freon in the system you were supposed to vacuum the lines and perform a leak test. If it can hold a vacuum, it can hold pressure! Most professionals will put a vacuum on the system and come back 24hrs later and see if it holds. Then, you release the freon... I think you void the warranty if you dont have a HVAC guy with a license#.
I am not trying to make you feel bad or anything, I was probably going to set up my own system. However, I have friends that have a valid Hvac license#. For the warranty, there usually has to be an invoice # proving that you hired a company...

Click to expand...

This is a stealth grow in a state that is still in the dark ages so getting an HVAC guy out to go into my tent is out of the question. I know I'm taking a chance on the warranty but it is what it is.....

This is a brand new pioneer 12000 BTU 13 seer (bought off Amazon for $671) I don't see any quick connects - are you talking about the service ports like on a car?

On installation, I ran a 33ft lineset, I don't have a torque wrench but I do have a set of gauges and a 5 cfm single stage pump. Initially, I evacuated the system and held a vacuum, I found there was a leak and tightened the fittings. Ran another vacuum and held it for a few hours and didn't see a drop. So I filled the lineset with 17 feet of refrigerant opened the valves to release the precharged freon and it blew ice cold. I did a soap test but I guess I missed a leak. After it started losing cool, I shut it down and brought in my old portable and am using it until I get this resolved. I bought I leak detector, got it in yesterday - found the fitting that was leaking the tightened it until there was no more leak.

So at this point, I would
- open up the valves on the high and low side and vacuum out the system - for a long while. Hold it for a long while and look for any drop. If all is good then:
- shut off the low side and vac on the manifold gauge,
- purge air from the refrigerant line
- open manifold refrigerant line
- open low side manifold line (purge?)
- Weigh in 9.51 lbs of refrigerant (2.25 system 7.26 lineset)

Would I start the system to cool after I start the refrigerant?

Thank you!

MustangStudFarm said:

I am going to be asking you plenty of questions. I started a Pioneer thread but it is dead. Not one reply. You are the only person that I have been able to talk to that owns a system...

Where the lines really cheap and shitty??? Faulty/missing pieces for the line set is the only negative review that I have seen about the system.
Experts will cut the flared fitting and braze the copper lines together.
You need to wake up and talk to me lol. The only reason that I have not bought this system is because they are on back-order until May18th.! I really want to know if it was faulty equipment or do you think that you messed up during install? I have seen one person talk about a missing copper gasket for the quick fitting. It cost him .50cents from Grainger.

Click to expand...

Hehehehh.... I'm awake! I really had no problems with the system, all the parts were there. I didn't even use the 16ft set that came with it, but it had all the parts. I know that my issue here is because I didn't tighten down the fitting enough. Is that what you are calling the quick connects? These are flare fittings, then again I might not know the terminology.

Professionals will vacuum the line and give it 24hrs for a leak test. If it is holding a vacuum for 24, you should be good...
They discontinued the 13 seer unit in 2015 due to new restrictions. I think that every system has to be 14+ seer now...

I noticed that they started to give away glue for connections with a new purchase.
http://www.amazon.com/Connection-Ductless-Conditioners-Prevents-installation/dp/B00QMS86WI/ref=sr_1_6?ie=UTF8&qid=1431189672&sr=8-6&keywords=pioneer+split+air+conditioner

There should be a maximum number of feet that your copper lineset could be. If you exceed the maximum number, you just need to add more 410. I will look and see if I can find the max ft for the lines

It is hard to find the spec for this unit. I came across others that say ,for example, their unit has enough charge for 25' lineset.

if it didn't all leak out, you don't need to pull a vacuum. If it went flat, then you can just pull the vacuum with the ports open. recharging is going to be another story.
you are probably running a 410a system. you need a license to buy that. then you have 2 ways of charging, you can weight out the charge and then check subcooling. or you can just wing it nd try and get it close by just checking the subcooling.

Open valves and vacuum the shot out of it for an hour or more and then close.of manifold gauges. Make sure it holds vacuum if it holds for 20 minutes your good. recharge it through low side Port. Cut mini split on and set to coldest temp to keep it running and charge to proper pressures. II believe the pressure are high 510 low 70 could be wrong read your sticker and charge it to proper pressures and therest ya go.

In an automotive system. "Winging it" is when the compressor stays cycling. The proper way is to weigh it though.

I am glad someone else chim'ed in!

This is more like the recovery system that I have been trained on. It has the recovery tank and scale inside the stand. All-in-one system!

http://www.amazon.com/Robinair-34288-CoolTech-Recycling-Recharging/dp/B0015DOPDE/ref=sr_1_2?ie=UTF8&qid=1431192620&sr=8-2&keywords=robinair+134+recovery

MustangStudFarm said:

In an automotive system. "Winging it" is when the compressor stays cycling. The proper way is to weigh it though.

I am glad someone else chim'ed in!

Click to expand...

134a is easy and you can buy it at o'reilly. charging it until compressor stops cycling works great. or they have a meter on the charge kit that tells you when it's good.
never heard of charging to a pressure of 510 and 70, that is a huge head pressure, to do it properly, length and size of pipe and subcooling all need to be considered for 410a

I was just explaining that I am no expert! Yeah, R134a is easy to get.

TGA Subcool used to be an A/C guy. That is how he got his name. I think that only people who know a little a/c understand it.

MustangStudFarm said:

Professionals will vacuum the line and give it 24hrs for a leak test. If it is holding a vacuum for 24, you should be good...
They discontinued the 13 seer unit in 2015 due to new restrictions. I think that every system has to be 14+ seer now...

I noticed that they started to give away glue for connections with a new purchase.
http://www.amazon.com/Connection-Ductless-Conditioners-Prevents-installation/dp/B00QMS86WI/ref=sr_1_6?ie=UTF8&qid=1431189672&sr=8-6&keywords=pioneer split air conditioner

Click to expand...

That's true, I got them with the unit and with the extra lineset I ordered.

MustangStudFarm said:

There should be a maximum number of feet that your copper lineset could be. If you exceed the maximum number, you just need to add more 410. I will look and see if I can find the max ft for the lines

Click to expand...

It's 50ft - I'm running 33

MustangStudFarm said:

It is hard to find the spec for this unit. I came across others that say ,for example, their unit has enough charge for 25' lineset.

Click to expand...

There's enough for a 16ft lineset - which they ship with the unit. Here are the specs:


Thank you for all your replies!

anzohaze said:

Open valves and vacuum the shot out of it for an hour or more and then close.of manifold gauges. Make sure it holds vacuum if it holds for 20 minutes your good. recharge it through low side Port. Cut mini split on and set to coldest temp to keep it running and charge to proper pressures. II believe the pressure are high 510 low 70 could be wrong read your sticker and charge it to proper pressures and therest ya go.

Click to expand...

Thanks for the reply! I hear that mini splits are critical charge system, so it has to be weighed in. I calculate it at 9.51 lbs - also, I don't have a high side measurement that I can take, that I know of.

chuck estevez said:

134a is easy and you can buy it at o'reilly. charging it until compressor stops cycling works great. or they have a meter on the charge kit that tells you when it's good.
never heard of charging to a pressure of 510 and 70, that is a huge head pressure, to do it properly, length and size of pipe and subcooling all need to be considered for 410a

Click to expand...

I assume it leaked out because it's not blowing cold but when I used the leak detector - it detected the presence of 410a. If there is any in there, it shouldn't be much. I already have an 11.5 lb can of 410a sitting here - bought it off the net.

cbdprospector said:

Thanks for the reply! I hear that mini splits are critical charge system, so it has to be weighed in. I calculate it at 9.51 lbs - also, I don't have a high side measurement that I can take, that I know of.

Click to expand...

I heard that they only have one service port! That is strange, especially since they expect you to hire a pro. Again, I may be out of my area of expertise.

Gotta love Ebay!!! I have a credit line with them lol.