Gas Heating & Hydronics

In Florida, there are not many gas furnaces—at least not as many as up north. Sometimes, we can look like real dummies compared to techs who work on them every day. One thing to know about 80% gas furnaces with cased evaporator coils is that you can often check the evaporator coil by removing the […]

The ignitor of a furnace (or a gas pool heater or other gas-fired appliance) is the heat source, and it can come in one of four varieties: standing pilot, direct spark (DS), intermittent spark (ISI), and hot surface (HSI). We have a tech tip explaining each of these ignitor types in detail, but we’re going […]

In the furnace sequence of operation, the ignition sequence happens after the safeties have been checked, the inducer fan comes on, and the pressure switch closes. The ignition sequence begins with the ignitor. This part provides the heat needed for combustion (remember: a fire needs heat, oxygen, and fuel), and the ignition process looks a […]

As we do fall maintenance and head into the heating season, combustion analysis becomes a big deal. (It’s always kind of a big deal, but now it’s a really big deal.) First and foremost, it tells us how much carbon monoxide (CO) is produced by burning. CO can make people ill, contribute to cognitive deterioration […]

I know, I know. You came here for HVAC content, so why are we talking about gas pool heaters? Since Kalos is based in Florida, and we don’t have that much of a heating season, we have to look for other forms of work during the winter months. Pool heaters fit the bill quite nicely […]

If you’ve been following my writing for the last couple of years, you know that I like to blather on and on about combustion analysis. Now, I am by no means an expert on the subject, as I live in North Texas (which is not known for its intense heating season), but I love using […]

Just like Shrek, I like to think about the heating sequence of operations as an onion—it has layers. And each layer builds upon the previous one. We have written previously in great detail about gas furnaces, from top to bottom. I want to focus today on why there is a sequence of operations and how […]

This tech tip was written by Casey Contreras. Casey is a field coach and instructor for the National Comfort Institute (NCI). Thanks, Casey! As HVAC technicians, our careers often focus on either cooling or heating. Because of this split view, we typically ignore gas-fired appliances during the cooling season. There are dangers lurking in any […]

This tech tip was written by Jennifer Manzo. Thanks, Jennifer! As an HVAC technician in Maine, I've seen my fair share of aging systems, but nothing quite prepared me for the sight that greeted me while responding to a “no heat” call in a multi-family apartment building this winter. Stepping into the boiler room of […]