HVAC161 Condensing unit leak search Tips

Leak search tips for the condensing unit.

Here is a link to an incredible leak search guide by by John Pastorello of ‪@refrigerationtechnologies‬
https://www.refrigtech.com/proper-hva...
I have no affiliation with them, its just a great article.

In this video we cover condensing unit leak search tips starting with the basics.
The valve cores should be leak checked with the caps on loose. Do not let leak detection bubbles come into contact with the calve core itself to prevent contamination of the unit or your equipment.

Replace plastic caps and caps missing the o-rings with brass caps.
Hex head brass caps do not use an o-ring and are torqued to 8 - 10 Ft. - Lbs. although I dont know of anyone who torques these. I do Recommend Nylog for the hex style caps.
2009 International Residential Code (IRC) and the International Mechanical Code (IMC) (updated in 2012) for Tamper-Resistant Refrigerant access valve port caps.

Residential, multifamily, and townhouse developments may be subject to significant fines stemming from the lack of enforcement of the 2009 changes to the International Residential Code (IRC) M1411.6 and International Mechanical Code (IMC) 1101.10 of the International Code Council (ICC), which require that all accessible access HVAC ports to be secured with tamper-resistant caps.
Never use leak lock or thread lock on valve caps!

Next check the Service valves covers as they often leak. I recommend NYlog to help seal these caps but never thread or leak lock. inspect the caps to ensure they have not ben overtightened.

Check liquid line filter driers, they are made of metal and will rust when outside. Sometimes they are inside the condening unit itself. check to make sure there is only one. When possible its best to install them inside.

Check for suction line filter driers they rust out ver often due to condensation. 410A systems should remain no longer than 72 hours

Check in accessories such as Suction line accumulators and Mufflers that are also made of metal.

Look for refrigerant oil leaks, as they can be a sign of a refrigerant leak. The oil could be left over from manufacturing service or a previous leaks. After you confirmed there is no leak clean up the oil spots for the next person.

Check to ensure wires are not rubbing any tubing as this also causes leaks. Cable tie wires together so they do not rub. You can also use foam tape on the copper and cable tie the wired to the copper with the foam between them. Do not connect any wires to the hot gas line to prevent damage.

Check high and low pressure switches for leaks and they too often leak.

Use a tarp around the condensing unit to stop air movement. this allows refrigerant to build up a concentration to be located easier. Take your time and slowly cover all bends, braze joints and the coil itself.

Check around the compressor, connections, wiring terminals, and the bottom of the compressor. A long buildup of leaves can cause the bottom of a compressor to rust out prematurely.

Still no luck? You can add a service port behind the service valve inside the condenser. Close the liquid line valve and pressure test the condenser up to the maximum test pressure on the high side only. It will pressure test from the liquid valve through the condenser to the compressor discharge line. The additional pressure can help you identify a leak faster.

For the suction side never exceed the low side test pressure to protect the compressor electrical pass threw connection. Copland calls this the fusite connection.

Take your time and good luck!