Condenser Install 3D
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Bryan explains some best practices for installing a heat pump condensing unit in Florida. He walks through the installation process from the warehouse to the final inspections.
The installation process truly starts at the warehouse, where we must make sure we have the correct unit and everything we need, including the concrete pad, heat strips, an appropriate circuit breaker, tubing insulation, UL-rated silver tape, and duct sealant. Some particularly Floridian components include duct board, hurricane straps, plywood, and corrugated tubing.
When you get to the site, confirm that you have the correct unit type by looking at the existing unit’s tonnage, the new unit’s tonnage, and Manual J and S calculations. Then, you check the disconnect to see if it needs replacement before removing the disconnect and making sure you don’t have 240v between legs or between one leg and ground. Check the data plate to make sure you have the appropriate circuit breaker and wire sizing.
Once you’ve verified everything, you can prepare for recovery. We recommend removing Schrader cores from both lines and using an inexpensive analog gauge manifold for recovery. Make sure you know the contents of your tank; if it’s empty, pull a vacuum on the tank to get the air out. Be sure to pay special attention to the water capacity (WC) and tare weight (TW) values on the tank, as you only want to fill the tank 80% for the refrigerant you’re recovering.
When recovering the refrigerant from the old unit, some best practices include using a liquid line filter-drier and inverting your tank while recovering. Keep going until your recovery machine reaches or goes just below zero. After recovering the refrigerant, you disconnect the electrical components. When replacing an old heat pump with a new one, you may either reuse or replace the copper line set. If you reuse the copper, you would need to do pipe-wiping to remove residual oil and clean out the lines with a foam pig, nitrogen, and a hose. If you need to replace the copper, you need to expose the chase and make sure you have enough room to run new copper. In either case, you will need to cut the copper and must take measures to reduce contamination.
We must also consider the drain. In Florida, indoor traps are uncommon, but they are industry standard. If you’re reusing the drain, you’ll need to clean it well; we recommend using water and a shop vac to clean the drain out well. Refill the trap when you’ve finished.
If you place a new concrete pad or route a new drain, try to keep those two feet from the house, each other, the dryer vent, and your disconnect.
When it comes to brazing new copper, the torch is critical to the success of the operation. Make sure everything is snug and that you turn out your regulators before opening the oxygen and acetylene tanks; try to keep the oxygen and acetylene both around 10 and 10. You’ll typically start off by opening the acetylene tank first, lighting the torch, and bringing oxygen in, but you could start to open both tanks around the same time once you get used to your equipment. You’ll want a neutral or slightly carburizing flame, not an oxidizing flame.
When brazing, heat the copper to a dark cherry red color to draw the alloy into the joint. Allow the copper to cool, and route the copper lines as needed. Once you have enough of the copper line inside the home, you can start bending it with proper tools, sealing the chase, and using fittings or bent connections.
When installing a new drain assembly, we put the sealant on the male end and hold the ends together. You only need primer if the system is pressurized.
After you seal copper at the condenser, you can pull your Schrader cores out. When brazing the rest of the joints, be sure to cover the sensitive parts with a wet towel or Refrigeration Technologies Wetrag to prevent damage, especially indoors. Let each brazed joint sit for at least 20-30 seconds before cooling them off with a wet towel. Clean them and inspect them with a mirror.
When your joints look good, you can do your pressure test. Use a spray-on bubble solution to check for leaks. Make sure there isn’t too much pressure decay over time. During the pressure test, you can work on your electrical connections and anchor your new condenser.
Once you prove that you don’t have significant leaks, you can release the charge, check the thermostat wire, and assess your line lengths to see if you need to add any more charge. As always, you will want to inspect the entire system once it has sufficient charge and clean up your work.
Setting a Charge By Subcool on a TXV system In 3D: https://www.youtube.com/watch?v=T4akG…
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