What if you Only Have One Large Hose?

When evacuating, the FASTEST way is to use two large-diameter hoses connected to two core removal tools and the cores removed. These hoses are then connected to the pump using a tee or evacuation “tree.”

However, when you only have one large hose, another acceptable method is to connect the large hose to the suction side and the vacuum gauge to the liquid side alone.

Brad Hicks from HVAC in SC made a nice little video showing how he does this with just one hose. He uses a core tool with the vacuum gauge on the liquid line to ensure that there aren't any issues with depressing the core, which frequently happens with certain cores and gauge couplers. The other reason is so that he can valve off the vacuum gauge when he releases the charge or charges the unit to prevent refrigerant and oil from potentially entering his vacuum gauge.

The disadvantage of this setup is that the vacuum must all pull through the metering device, which can add time to the process. In the case of a “hard shut off” TXV, this method may not work.

Transcript

What's going on, guys? Here's another 60-second tech tip video. This one's going to be on single hose evacuation setups. I get tons of questions on the subject, so hopefully, this will clear things up a little bit. It's very, very simple. All I have is two Appion core removers here. Both cores, liquid and suction, have been removed. On the liquid side, I have my micron gauge. In this case, the BluVac+ Pro, and on the suction side, I have my Appion hose. This is a six-foot (1.82 meters), 1/2″ diameter 1/4″ by 3/8″, and then, of course, my vacuum pump—no special fittings or anything anywhere—very, very simple setup and very effective. Just to give you an idea, I'm in a decay test right now, but I've been running a total of 24 minutes right now, and my decay test has another two minutes. I've set for a 10-minute decay, so another two minutes, and we'll be good to go. And as you can see, [I've got the] single hose setup—very, very effective, and as you can see, I have it isolated. I'm still reading my micron gauge and everything in the system. So, I hope that helps. Just a quick rundown—if you have any questions, feel free to ask.

—Brad Hicks, HVAC in SC

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Related Tech Tips

Density of Air & Water Part 2
Here is part 2 from Michael Housh from Housh Home Energy in Ohio. Thanks, Michael! This is part two in a series on a deeper look into the sensible heat rate equations. You can find the first article here HERE if you missed it. This article will dive deeper into the density of “standard air” […]
Read more
Does Nitrogen Pressure Change with Temperature - Practical Application of Gas Laws
The gas laws. We all learned about them in school and promptly forgot all about them. I really think that we need to dig our books out, dust that information off, and work to understand and apply it. Many will say that nitrogen pressure doesn't change with pressure like other gasses. That is false, but […]
Read more
Historic Homes: Handle with Care
This article was written by Sam Myers with Retrotec. Thanks, Sam! If you’ve ever lived in a historic home, you’ve likely noticed that the level of comfort can change throughout different parts of the house. It can also typically change throughout different times of the year, depending on your climate. That is primarily due to […]
Read more
loading

To continue you need to agree to our terms.

The HVAC School site, podcast and daily tech tips
Made possible by Generous support from