Gary McCreadie is an HVAC tech, the creator of hvacknowitall.com and the HVAC Know It All Podcast Refrigeration Cycle Explained To set this up properly, I really should bring up the first time I put some lackadaisical thought into refrigeration or air conditioning.  I was a young teen walking by the side…

Joshua Rees is an industrial refrigeration technician, father of six beautiful children and a husband to his beautiful wife Jessica.  Joshua has been in the industry since sixteen and started his career in the commercial HVAC/R industry.  During a conversation with some of my peers, the subject was brought up about oil loss in screw…

Gary McCreadie is an HVAC tech, the creator of hvacknowitall.com and the HVAC Know It All Podcast This short podcast also covers this burner repair in detail   The Problem This heating tip was generated from some on site aggravation while repairing a burner.  During the initial preventative maintenance, it was discovered that the 1st…

Gary McCreadie is an HVAC tech, the creator of hvacknowitall.com and the HVAC Know It All Podcast A General Guide To HVAC/R Troubleshooting This is a general guide to HVAC/R troubleshooting.  We won't be getting into specifics that involve local codes, OEM procedures and guidelines or in-depth analysis of things like static…

Gary McCreadie is an HVAC tech, the creator of hvacknowitall.com and the HVAC Know It All Podcast When working on small, self contained reach in coolers and freezers, you’ll notice many of them are not equipped with service access valves for testing, evacuation and recovery.  This makes it difficult to troubleshoot if…

Gary McCreadie is an HVAC tech, the creator of hvacknowitall.com and the HVAC Know It All Podcast The science on how we pull an evacuation on air conditioning and refrigeration systems has changed over the years.  Back in the day, technicians would purge refrigerant through the system to remove air, moisture…

Matthew Showers is an HVAC service technician, performing work in both the residential and commercial fields.  His specialty is in inverter and communicating systems.  Follow Matt on Instagram  As environmental regulations change, manufacturers of HVAC equipment are being forced to find refrigerants that are not only environmentally safe, but also perform…

Matthew Showers is an HVAC service technician, performing work in both the residential and commercial fields.  His specialty is in inverter and communicating systems.  Follow Matt on Instagram  As the world gravitates to higher efficient equipment, manufacturers are looking to create solutions that are both effective, but also practical from a…

  Patrick Lange is an experienced HVAC specific business broker with Business Modification Group.  Most HVAC businesses start with an ambitious and talented technician that dared to take the leap and open their own shop. Somewhere along the way, they will get frustrated and realize their income is capped by the hours…

It was a warm August day, myself and my co-worker were digging into some PM work.  We found one of the Carrier RTUs without power and the breaker tripped.  

"This one time, at band camp," is a famous line you may remember from the movie American Pie.  Although the narrative, as it pertains to this article goes as such, "this one time, in residential". 

Expansion valves are used to inject refrigerant into the evaporator of refrigeration and AC/HP systems at a condition that will allow the refrigerant to absorb heat.

To obtain reliable performance with solenoid valves on refrigeration or air conditioning systems demands careful consideration of application requirements during the selection process.

Air balancing is an important step in HVAC commissioning. Every forced air system should be balanced upon initial startup, and some engineers or city officials may demand it before final approval.

It’s that time of year again when the clocks fall back and so does the temperature outside. There are a number of items that should be inspected when the building is being changed over from cooling to heating. The main heating and cooling components such as chillers/cooling towers and heating…

Most of my hard core learning came in the early days of my career.  I was thrown into many situations I probably had no business being involved in and like most young apprentices, there were more than a few royal f@#k ups.  I remember vividly, my first encounter with non…

Make up air units or MUA as they are commonly referred to play a vital role in your condominium. The building MUA unit is generally located at the top of the building, either in the mechanical room or out on the roof. The function of the MUA unit is in…

In early 2018, Testo introduced the 440 air flow testing and measurement kit.  It's a fully comprehensive kit that offers many functions.  One clear advantage, is that all the probes are available in Bluetooth to avoid wire clutter.  It gets better, the cable handle and Bluetooth handle are compatible with…

Checking/testing gas fired appliance manifold pressure is an integral part of service, maintenance and unit start up for optimal performance.  It could be the difference between a properly functioning system to a potentially pre-mature failure of a heat exchanger and more...Under fired or over fired appliances like furnaces, boilers, and…

Most gas fired appliances these days use flame rectification to prove the pilot flame before initiating the main burner.  Flame rectification is the process that uses the flame to convert an AC signal to a DC current (micro amps). There is a specific way to test the signal strength, the right knowledge and…