Mike Dolt Enterprises
Mike Dolt Enterprises
User: monomial, Location: Clarkston, WA
Asked on: Thursday, June 26, 2025 at 5:04 pm EDT
Answered on: Thursday, June 26, 2025 at 8:00 pm EDT
Question: Hi everyone,We just moved to Lewiston ID/Clarkston WA. It was very hot and so decided to order and install a mini split air conditioner. Install went OK, and it seemed to work for about 3 minutes, but since then it fails with a P3 code and blows warm air. I am assuming there is no longer any refrigerant. We did cut the line and reflare the copper tubes during install because the ones shipped with the unit were too long. I'm assuming that is where the problem occurred.Before turning it on, we pulled a vacuum on it for about 15 minutes. It seemed to draw a good vacuum, but I didn't have any way of disconnecting the vacuum pump to see if the pressure would hold over time, so there very well could have be a slow leak. The evidence sure seems to indicate there is.At this point, I have called around to everyone in the Clarkston/Lewiston area and nobody will look at it because it was a self install.It's an R32 unit, so I don't have the equipment to work on it myself. I understand the theory behind A/C, and work on the unit in my car, but I don't have experience with these mini split models or R32 in particular. The installation manual did not come with any tables for the appropriate pressure we should see, or how much refrigerant to fill. Is there an industry standard for this? It's a 24,000 BTU model.Can anyone suggest what I should do now? Does anyone know of a tech in the Lewiston ID area who will take a look at it for me?Any advice is appreciated.Best Regards,Chris Ziomkowski
Okay, Chris, this is a frustrating situation, but let's break it down and see what we can do. You're right, the P3 error code usually points to a refrigerant issue, and your self-install re-flare is the most likely culprit.
Addressing the Immediate Problem (Refrigerant Leak & P3 Error)
Confirmation of Leak
You're right to suspect the flare connection. Even though it looked okay, a tiny imperfection can cause a slow leak. This is the most common issue with DIY mini-split installs.2.
R32 Precautions
R32 IS mildly flammable. This is the main reason pros are hesitant to touch DIY installs. It requires specialized tools, procedures, and safety training. DO NOT attempt to add refrigerant yourself without proper equipment and training. You could create a dangerous situation.3. Finding a Technician
This is the biggest hurdle. Here's a multi-pronged approach:
Expand Your Search Area
Look beyond just Lewiston/Clarkston. Check in surrounding towns within a 50-mile radius.
Reframe Your Request
Instead of saying "I installed it myself," try saying: "I had a new mini-split installed, and it's throwing a P3 error code. I need someone to diagnose and repair a possible refrigerant leak." Don't lie, but focus on the current problem rather than the history of the install. If they ask who installed it, be honest, but emphasize you understand it needs professional attention.
Appliance Repair Shops
Call appliance repair shops in addition to HVAC companies. Some might have technicians qualified to work on mini-splits, even if they don't typically advertise that service.
Mobile HVAC Technicians
Search online for independent or "mobile" HVAC technicians in the area. They might be more willing to take on a one-off job.
Online HVAC Technician Finder Services
Use services like Angi (formerly Angie's List), HomeAdvisor, or Thumbtack to find HVAC techs in your area. Describe the problem clearly and be upfront about the DIY aspect.
Contact Mini-Split Manufacturers (Less Likely)
Call the manufacturer of your mini-split unit. They might have a list of certified installers or technicians in your area, although this is unlikely for DIY installations.4.
If you must DIY, proceed with caution
Leak Detection
If you can find the leak, you may be able to fix it, but will still need to have the system evacuated and charged with refrigerant. I would start by spraying soapy water on each connection and watching for bubbles.
Flaring Tool Quality
Use a high-quality flaring tool designed for HVAC lines. A good flaring tool creates a smooth, consistent flare that is less prone to leaks.
Torque Wrench
Use a torque wrench to tighten the flare nuts to the manufacturer's recommended torque specifications. Over- or under-tightening can both cause leaks.
Evacuate
It is critical that any moisture or air is evacuated from the refrigerant lines.
Understanding Refrigerant Pressures and Charging
No Industry Standard Chart
There isn't a single industry-wide chart for R32 pressures because the optimal pressures depend on several factors:
Ambient Temperature
Pressure readings change with outdoor temperature.
Indoor Temperature
The indoor setpoint affects pressures.
Unit Load
How much cooling is being demanded.
Refrigerant Charge
This is what you're trying to determine!
Superheat/Subcooling Method
HVAC technicians typically use a superheat and subcooling method to properly charge a system. This involves measuring the temperature and pressure at specific points in the refrigeration cycle. It requires specialized tools and knowledge.
Refrigerant Charge
It will vary. I highly recommend getting a professional's opinion here.
Unit Label is Critical
Look very closely at the outdoor unit's label. It might contain the refrigerant charge amount (in ounces or pounds) for a system with specified line set length.
Important Considerations Before DIY (If You Still Consider It)
Liability
If you damage the unit or, worse, cause an accident, you're liable.
Warranty
DIY installation likely voids the manufacturer's warranty.
Safety
R32 is mildly flammable.
Summary of Action Steps
Exhaustively search for a qualified technician willing to work on your system. Try the rephrased request, broaden your search area, and contact appliance repair shops and mobile techs.2. If a technician agrees to come, let them handle the diagnosis, leak repair, evacuation, and refrigerant charging. This is the safest and most reliable option.3. If you are able to diagnose the problem, but cannot resolve it on your own, find a technician to come and fix your repair.4. If professional help is absolutely unavailable and you choose to DIY, proceed with extreme caution. Research proper flaring techniques, use high-quality tools, and never* work with refrigerant without proper training and safety precautions.Good luck! Let me know if you have further questions or find a technician in your area. I'm here to help if I can. Flag for review