Last week the condensate line on the wall-mounted ductless mini-split in my sunroom clogged. It didn't take long to discover the problem because I saw water on the floor below the unit. Since that happened on a Monday, I turned…
One of the biggest fears of HVAC contractors is to undersize a heating system. I'm not saying it's impossible, but installing a heating system that won't keep a house warm is really hard to do. Sometimes the rules of thumb…
![How Many Installation Problems Can You Identify In This Photo Of An Energy Recovery Ventilator In An Unconditioned Crawl Space? [Photo By Robert Jordan Of Achieve Home Energy Advisor]](https://www.energyvanguard.com/wp-content/uploads/2025/10/energy-recovery-ventilator-erv-bad-installation-1.jpg)
How many ways can one screw up an ERV installation? Surprisingly many, as it turns out. And to look at their work, it seems that some installers think that maximizing those installation errors is the goal. I'll get into the…
It's time for another update of my ongoing personal heat pump case study. I wrote here in 2020 about how the inverter-driven mini-split heat pump serving most of my main floor is undersized for cooling and for heating. And I…
Yeah, I'm talking about a heating and cooling load calculation. Or in HVAC-speak, an ACCA Manual J. It's a way of calculating how much heating and cooling a house needs. The calculations use the details about the house to determine…
I've been making a statement for a long time that sometimes gets called out as inaccurate. The story began in the second month of this blog back in April 2010 when I wrote an article titled When Is 100% Efficient…
Let's talk thermostats today. This ubiquitous device in homes is the user interface that allows people to control their heating and cooling systems. It might seem simple. Turn it up when you need more heating or cooling and down when…
Do you know how to read a roof after a snowstorm? When you do, it tells you something about how good the building enclosure is. We had that opportunity here last weekend. We got 2 or 3 inches of snow…
Have you ever used a flashlight to look up into the part of a ductless mini-split where the air blows out? I should have done that a lot sooner than I did. It turns out these heat pumps can get…
Unless you have a simple, small home, you probably want more than one thermostat to control the heating and cooling. That lets you control the conditions separately in different areas. And that's where zoning comes in. A common example is…