Ductless mini-split installations can be complex if you don't plan and strategize properly. However, installing a Mr. Cool DIY ductless system is easier than most because of its simple engineering and clear instructions. Like any DIY project, though, there can be some surprises along the way.

We had the chance to interview Andrew, a Got Ductless customer who installed a 2-zone Mr. Cool DIY system in his basement apartment. Andrew shared five surprises he encountered during his installation, and we want to pass them along to you.

Andrew lives in Dillsburg, PA, where he has a separate basement apartment. He wanted to keep the apartment's HVAC system completely separate from the main house. The apartment includes a main living area and a separate bedroom, with a bathroom in between. Since the bathroom is surrounded by conditioned space, it didn’t need its own unit.

For the system design, Andrew chose a 9k unit for the bedroom and a 9k unit for the main living space. Both indoor units are connected to an 18,000 BTU, 2-zone outdoor unit. He used a 16-ft and a 35-ft line-set to connect the units. Given the smaller size of the basement, he didn’t anticipate needing future expansion, making the 2-zone system a perfect fit.

Andrew knew he wanted two indoor units for zoning, but he also had to work around pre-determined line-set lengths. Originally, he planned to place the main unit on the back wall of the apartment, the same wall as the outdoor condenser. However, after consulting Got Ductless, he realized he needed to move the indoor unit to avoid coiling the 16-ft line-set underneath the outdoor unit. This change also allowed for better air distribution. Once he sent his new plan to Got Ductless for approval, he received valuable suggestions that helped finalize the layout.

One of the line-sets was the perfect length, while the other required one small coil due to obstacles like windows and doors.

Now, let’s dive into the top five surprises Andrew encountered during his Mr. Cool DIY installation:

Here are the 5 Surprises

1. How Long it Takes to Install
2. Hardest Roadblock we Ran into 
3. Read the Instructions
4. Unit Performance (Positive)
5. Cool Way to Save Money

Let's go through each one in detail.

Andrew found the project simpler than he anticipated, but, as with any DIY task, preparation is key. The most time-consuming part was securing the line-sets and line-set covers to the cinder block exterior. “It seemed fast and easy at first, but finding the right size Tapcon screws and securing everything properly took longer than expected,” Andrew shared.

Having the right tools and materials is crucial. While Mr. Cool provides a list of necessary tools, the details can vary depending on your specific installation. Got Ductless helped Andrew ensure he had the right materials, which made the process smoother and more efficient.

Reading the instructions saved Andrew time in some areas but led to a mistake in others. When connecting the control wire to the outdoor unit, Andrew assumed the wire colors would match up. After reading the instructions carefully, he realized the wires were letter-coded rather than color-coded. This saved him hours of troubleshooting.

However, when starting up the system, Andrew encountered an error code on the indoor units. After some research and another look at the instructions (with a call to Got Ductless), he realized he had forgotten to open the service ports, preventing refrigerant from flowing through the system. “It’s tempting to skip over the instructions, but in the end, they saved me from a lot of headaches,” Andrew admitted.

One of the biggest surprises for Andrew was how quiet the Mr. Cool DIY mini split system was compared to his older, noisy whole-house heat pump. “I didn’t even think it was working at first because it was so quiet,” Andrew said. Once he felt the heat coming from the indoor units, he realized how efficient and powerful the system was. He was impressed by the quiet operation and effectiveness of the system.

Let's review. Here's a quick recap of the top five most surprising things that Andrew the homeowner realized during and after his DIY installation.