I hope everyone had a very nice Christmas.

I have a mini split by Fujitsu that services my bedroom. Back in the spring I noticed it was not giving cool air anymore so of course I didn't use it all summer. This fall when I checked to see if it would give me heat I got a system message that told me it won't work because of low coolant. I didn't think low coolant would NOT give me heat but that's the way it's designed. I would like to get this thing working again so I am planning to see if I can figure out where the leak is. I have a coolant line that goes from the condenser outside up to my bedroom to the a.c. unit on the wall. I am going to check that coolant line to see if perhaps either of the connections are loose. My question is are there any other places the freon might have leaked. If I find a leak in the coolant line I will just order another line and replace what's there. I also had some roofing work done in the past year so I don't know if something happened with that yet. Any thoughts on this? Thank you.

Rich

 

Typically with a line set there are four connections. Two at each end of the dual line set. Since those are threaded fittings..... not brazed..... they are the most commons leak locations.

If you don't find anything loose..... you'd need to bring in a tech who could charge the system with nitrogen to locate a leak. If you were just slightly low you could have the system recharged and checked with a refrigerant leak sniffer.

 

This site doesn’t allow discussion on refrigerant charging or anything that requires an EPA license.
That said, your system uses refrigerant for both heating and cooling. It’s a heat pump.
You may luck out and find a leak due to oil accumulation around the leak point. But your likely going to have to pressurize the system with nitrogen to locate the leak.
Once found and fixed the system has to be properly prepared for recharging.
Leaks can be anywhere. Most are around flair fittings. If the flair is tight and still leaks then the flair can be redone.

 

Thanks you guys. I don't have the equipment to recharge so I'm hoping to find a leak then hire an HVAC man to charge it, like I did when I first got it.

 

Just remember, you may need equipment to even find the leak.
What test pressure did the unit hold when it was installed, and for how long?
Most of these minis want ~600 PSI for around 24 hours.

 

I don't know any pressures. I did check the four fittings and they all are tight. When I cracked on of them open just a tiny bit there was pressure so I tightened it right away. I am going to call a repair man because it does me absolutely no good the way it is. I can get an estimate and then decide if I want it fixed. Thanks for your help.