Does Freon Leak If My AC Is Turned Off?

The generic name for the brand name Freon is refrigerant. Several companies manufacture refrigerant such as DuPont (Freon), Mil-Spec Industries, MexiChem, and others.

Your home’s AC system is built to contain the refrigerant that it’s filled with. Unlike the rumors that you hear about car air conditioners that if you don’t run them from time to time that the seals will leak.

If your home outdoor AC unit or heat pump will not leak if it’s either on or off unless a leak is created in the sealed system by either vibration or a loose fitting. If a leak is present in the system it will leak regardless if it’s either on or off.

I’m sure there are some technicians out there who would argue this point so let me just say there are some rare exceptions especially with the new refrigerant R410A that all residential units are currently being charged with at this time.

R410A operates at a much higher pressure than it’s predecessors. Although I’ve never run across such a condition I remember in the initial training given when R410A was being introduced we were told how a very small leak could emit a force of refrigerant so powerful that it could cut or wound a technician.

Don’t believe everything you are told or read………………………….

The pressure of R-410A is so high that if your hand gets in the way of a leak, it could cut a finger off. This is a myth, as well as a physical impossibility.

This article from ACHR News states that over time which has been nearly 20 years that there has never been an incident of this type of injury from R410A refrigerant.

But the possibility of leaks is much greater given the higher pressure of the new refrigerant.

It just goes to prove that no matter who you listen to you have to prove it for yourself. No matter how deep we dig for information the trust can only hold so much pressure or only goes so deep.

How Can I Tell If My AC Is Leaking?

There are some simple things you as a home owner can do to sort of verify if your system is leaking or low on refrigerant. We have two scenarios. One is for a cooling only unit, not a heat pump.

  1. Cooling only unit or what a lot of people call just air conditioning.

So it’s summer time and you want to know if you AC is leaking or low on refrigerant.

With the thermostat turned on and the indoor fan running, go to the outdoor unit.

If the fan is running on the outdoor unit and the system has been on for more that a couple of minutes (it needs time to build pressures) locate the copper tubes that go into the house.

I’m assuming you have a split system. The link will send you to my article on what a split system is all about.

You need to find the largest of the two pipes. That pipe is called the suction line. Find a place where you can put your hand firmly around that larger pipe.

Remember it should be a pretty warm day.

With your hand in good contact with the pipe and the system on for more than just a few minutes it should feel like what we call pop bottle cold or some would say beer bottle cold.

Think about that cold bottle on a really hot day. Water molecules dripping between your fingers and that first big gulp. Anyway that’s what that pipe should be like.

The temperature difference between this really hot day and the suction pipe is great enough to create those same water molecules on the suction pipe.

If your suction pipe is well insulated as it should be, you may not have those water droplets showing, but it will be good an cold if you peal back some insulation. You can always tape it back into a good seal after you cut it back.

Just take a knife and cut a slice down the length of the pipe about six inches and squeeze your hand around the pipe inside the insulation.

So if you have a nice warm day and the unit has been running for some time to build pressures and you don’t feel that cold sensation on the pipe you may have a leak or a compressor that is not running.

Could be a simple fix like a capacitor but hopefully not a failed compressor.

2. Scenario two is a heat pump

Everything will be the same in scenario number two as in number one except that you do some similar checks in the cold of winter.

So now assuming it’s winter time and you want to do a check on if you have a refrigerant (Freon) leak.

Everything will be the same except, that larger pipe is no longer the suction line. Your heat pump has reversed itself and that beer bottle cold line is now filled with hot gases from the compressor and should now be pretty darn hot!

Remember that this cycle needs to be on for more that an few minutes and if your large diameter pipe is not very warm then you may have lost some refrigerant.

Anyway if its that same temperature or close to temp of the other smaller pipe it’s time for a service call.

How To Check For Freon Leak In Home AC

We’ve gone over a simple way of checking for leaks in a home’s AC system. One of my service calls just recently was to a heat pump that was not heating well.

The outdoor unit was running continually and the indoor fan seemed to never shut off.

When we started the unit I could tell that something was wrong just by the sound. An experienced ear at work here. There are a lot of things I can’t hear anymore.

So I applied the hand on the large copper pipe thing we’ve been discussing here and it was very cool in the heat mode and in winter of course. My next step was to hook up my gauges and just as I suspected it was low on refrigerant.

I did a thorough l look over of the outdoor unit for spots of oil. Because oil will follow a leak and leave residue. There was no visible sign so we went into the indoor section of the furnace and refrigeration coil.

It was obvious right of the bat. Oil dripping from the TXV valve in front of the coil. With a couple of wrenches I snugged up the valve and charged the unit.

There may be times when the oil doesn’t follow or drip out of a leak. In that case you may want to mix a little batch of dish soap in a spray bottle and go over some of the welds and fittings on your system or you may not.

So Now You Know What Causes Freon Leaks In Air Conditioner Systems

You are armed and dangerous now. Just a couple of easy DIY checkups and you can stop fretting over the idea of a refrigerant leak. You also know the correct name of the gas inside you system.

I hope your diagnosis was a good one and didn’t result in an expensive service call. If you have more questions please search this site to see if I’ve addressed your problem already.

Since you’ve read this far, why not travel just a bit further and scope out a couple of my favorite heating and cooling products and tools.

Thank you for reading my article. I hope the information has led to your ability to make good decisions in either working on or discovering how to solve problems in your home HVAC equipment. These are affiliate links, so if you do decide to use any of them I do earn a commission. In all honesty they are products that I would use in my own home or the homes of my friends and family.

Fireplace remotes by Skytech Remote Control Products . My wife loves this and it probably took all of 30 minutes to install. Replace that wall switch or thermostat for your gas fireplace. Easy installation and instructions. In fact I wrote an article that covers the job pretty thoroughly I think.

Honeywell Thermostats. My favorite two Honeywell stats are the T6 Pro and the 8000 Pro series but their is a bunch to select from besides those two models. You can select WiFi that has the capability of operating your system from your smart phone no mater where you are. Honeywell tech support for homeowners is the best out there. Call them if you need at 800-468-1502 or comment below if you have questions.

Fieldpiece HS33 Expandable Manual Ranging Stick Multimeter for HVAC/R. I carry two of these in my service truck. Just like a spare tire, when I get out away from everything, it’s no time for a break down. The Fieldpiece HS33 gives me the ability to do any aspect of my trade. I can measure motor or element amps, check capacitors, and AC or DC voltages. Even different scales of OHMS for finding shorted windings or grounded conductors in motors or compressors.

Chad Peterson

Chad Peterson is near 40 year veteran of the HVAC industry. "I like to explain heating and air conditioning problems in a way the average home owner can understand. "

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