I mainly talk about air source heat pumps here. But ground-source heat pumps are an important type of heat pump, too. So today, let's look at the issue of open-loop vs. closed-loop design when installing this type of heat…
So you think you understand psychrometrics, eh? OK then. Let's do a little quiz today and test your psychrometric knowledge. These questions include some basic stuff and some more complicated stuff about the subject, but you don't need to use…
Windows are thermal bridges in pretty much every home. The best windows available have an R-value of only about 12. More affordable windows are in the R-3 to R-6 range. Wall R-values are in the 13 to 15 range on…
We do a lot of HVAC design (third party, all over the US) at Energy Vanguard. I've also written a lot about it here in this blog and in my book. And if you've been reading any of those pieces,…
I'll be hitting the road with a car full of books in a couple of days. I'm heading out for a building science book tour of the Northeast. My first book tour event is in Rochester, New York next Tuesday,…
A little over a year ago, I wrote about the Emporia Vue home electricity monitoring system I installed at my house. I've posted data on LinkedIn and in some other articles since then. Now, though, I've got a whole year's…
One way of categorizing heat pumps and air conditioners is by how much heating and cooling they can provide. By how much, I’m not referring to, say, a 2-ton versus a 3-ton air conditioner. What I’m talking about is whether…
Sizing an air conditioner (or heat pump) shouldn't be left to guesswork. That's why we have engineering protocols like ACCA Manual J for calculating the amount of cooling load a house experiences. Among the factors that contribute are the outdoor…
So you're getting a new air conditioner! Well, what size should you get? Unfortunately, too many contractors use only one input for sizing an air conditioner. Yup. To them, it's just a matter of floor area. Forget the windows, the…
We've been trained to believe something that's just not true. Go out and ask a hundred people how long a water heater can last, and the majority probably will say it's in the range of 10 to 15 years. Where…