Step-By-Step Guide to Test A/C Efficiency! - Ballard Plumbing Heating & Air Conditioning

You know your A/C is working the best it could be … right? If not, and if you feel like it should be keeping you cooler without all the fiddling with the thermostat, read on:

We’ve put together a very easy step-by-step guide so that you can test out your A/C’s exact efficiency level, just like a pro would be able to do! In fact, if you can do this, then we’ll make you an honorary technician on our Ballard team! (Just kidding … but you will be proud of yourself for this skill!)

Without further ado, here’s how to test if your A/C is not working its best and is costing you money.

1. Make sure the system has been running for 15+ minutes

This part mostly goes without saying, but if you want to test how efficient your A/C is you need to give it a chance to fully turn on and get into its “groove.” So, if you’ve only just started running the A/C, give it at least 15 minutes first before doing this test. Also, another great rule of thumb is to change your HVAC filter first, before the test, because one reason for efficiency issues is a dirty filter.

2. Take the temperature of the air blowing out the supply vent

Next, you are going to need some kind of digital thermometer. We know not everyone has one, but you can easily find them at any major retailer for as little as $5. Put it on top of the register. (We are assuming the supply vent is on the floor; if not, because where it’s placed depends on your HVAC system and on the construction of your home, then you’ll have to hold the thermometer in place yourself as cold air passes over it.) About 5 minutes is required to get an accurate temperature reading. Then, take note of the final temperature!

3. Take the temperature of the air entering the return vent

Again, if you’re not sure whether a particular vent is a supply or return vent, one way to check is by holding a piece of paper in front of it. If the paper wants to cling and stick to the vent, that’s a return vent. (With good air flow!) If air is blowing out, that’s a supply vent, “supplying” air to your home. Once you’ve been taking the temperature right in front of the return vent for 5 minutes, it’s time to get your final result.

4. See whether your A/C is efficient!

For a perfectly-working A/C system, the supply vent temperature should be at least 15 degrees cooler than the return vent temperature. Otherwise, the air coming into your home is not actually cooling things down much, right? So, if the temperature difference between the two vents is less than that for you, your system isn’t working the way it should … costing you comfort, and money on your cooling bills! If you have a new filter, and yet this is the result, it’s time to bring the experts into your Inland Empire home. Ballard will get your A/C working again! Schedule an appointment online or call now: 909-297-1914

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