Pilot Controls - Short #147
HVAC School - For Techs, By Techs
Bryan Orr
4.9 • 1K Ratings
🗓️ 14 June 2022
⏱️ 7 minutes
🧾️ Download transcript
Summary
In this short podcast episode, Bryan talks about pilot controls. He talks about the old-school ignition systems on gas appliances and some similar pilot functions on residential A/C units and heat pumps.
When we think about a pilot light on a gas appliance, we can think of it as a small standing flame that sits there ready to ignite the burner whenever gas is flowing. Pilot lights were necessary for old-school gas furnaces, and many of those pilot lights worked with a thermocouple. In many older furnaces, pilots also prevent excessive carbon monoxide from unspent gas. In other words, the pilot is not the main burner; it merely sets up the main burner.
On a typical A/C system, the 24v power is similar to a pilot on a gas appliance; the 24v "pilot" control energizes the system and has a small amount of voltage (compared to the high voltage needed for all of the components to work).
The reversing valve on heat pumps also has a pilot valve; the 24v signal activates the pilot valve with the solenoid, which redirects system pressure to allow discharge gas to slide the valve. That's also why you can't shift the operating mode when the system is off. Solenoid valves in general tend to have pilot functions; they rely on a refrigerant pressure differential that results from 24v electrical signals, not the signal itself.
In short, we don't rely on the pilot light or the 24v electrical signal to power the entire equipment. Pilot controls merely help the equipment get started; they have less load on them and trigger or control parts and processes that are more complicated.
If you have an iPhone, subscribe to the podcast HERE, and if you have an Android phone, subscribe HERE.
Check out our handy calculators HERE.
Transcript
Click on a timestamp to play from that location
| 0:00.0 | Hello, hello, this is the HVAC school podcast. This is a short episode of the |
| 0:08.2 | podcast that helps you remember some things you might have forgotten along |
| 0:11.1 | the way, as well as helps you remember some things you forgot to forgotten along the way as well as helps you remember |
| 0:13.2 | some things you forgot to know in the first place. And before we talk about pilot valves or pilot |
| 0:18.0 | operation or pilot controls, I guess really pilot controls because we're going to talk about |
| 0:21.8 | some things that certainly are not valves. |
| 0:23.7 | Before we do that, we want to thank our great sponsors. |
| 0:26.7 | Refrigeration Technologies at refrigetech.com. |
| 0:31.0 | Carrier and carrier.com. Fieldpiece and Field Piece. |
| 0:35.0 | Field Piece makes so many great tools that it's hard to mention them all but they do have a new large pipe clamp that you're definitely going to like. It goes up to four inches and it works |
| 0:44.8 | great if you are in the more industrial sides of our industry. A very, very accurate, great |
| 0:50.3 | form factor. We tested it out at Kailos and we really love it. |
| 0:54.1 | Find out more by going to fieldpiece.com. |
| 0:57.0 | Speed clean and speed clean.com they make the coil jet if you ever find yourself in a |
| 1:01.6 | position where water or power are difficult to get when you're doing a cleaning job either an evaporate a coil or a condenser, especially a condenser, take a look at the coil jet. |
| 1:11.0 | It's made right here in the U.S US of A. It's a great product that does the job |
| 1:15.6 | reliably. That's the coil jet from Speed Clean. |
| 1:18.6 | All right, so when we hear the term pilot, this is just a general concept and it's useful for you to kind of remember this. |
| 1:27.0 | Think about a pilot light on a gas furnace or on a water heater or on a boiler or whatever you're working on that has a pilot light. |
| 1:34.0 | A pilot light is just a standing flame that sits there ready to ignite the burner. |
| 1:40.0 | So it's just on all the time and it's there so in case gas is flowing it's going to |
| 1:43.9 | ignite in the case of your old school furnace that was a necessity because you did |
... |
Please login to see the full transcript.
Disclaimer: The podcast and artwork embedded on this page are from Bryan Orr, and are the property of its owner and not affiliated with or endorsed by Tapesearch.
Generated transcripts are the property of Bryan Orr and are distributed freely under the Fair Use doctrine. Transcripts generated by Tapesearch are not guaranteed to be accurate.
Copyright © Tapesearch 2026.