Comments on: Don’t Confuse Design Temperature With Degree Days https://www.energyvanguard.com/blog/dont-confuse-design-temperature-with-degree-days/ Building science knowledge, HVAC design, & fun Sat, 03 Jul 2021 18:12:06 +0000 hourly 1 https://wordpress.org/?v=6.6.2 By: Cindi https://www.energyvanguard.com/blog/dont-confuse-design-temperature-with-degree-days/#comment-15718 Sat, 03 Jul 2021 18:12:06 +0000 https://energyvanguard.com/?p=5220#comment-15718 Somehow there is a fallacy in there when both of those homes (and in some cases the difference is even more dramatic) need to install the same size system. Particularly because so many systems that are large enough to meet peak load do not modulate well to lower loads. I’m starting to think that if you have a highly insulated / non-leaky home which can sustain its temperature longer, you should be able to design to much less than the 99%. There’s always space heaters and fireplaces and god-forbid blankets and sweaters for the very rare “cold snap.”

]]> By: Allison Bailes https://www.energyvanguard.com/blog/dont-confuse-design-temperature-with-degree-days/#comment-13977 Sun, 04 Apr 2021 14:57:54 +0000 https://energyvanguard.com/?p=5220#comment-13977 In reply to Jon.

Jon, the design temperature will be exceeded, on average, only 88 hours a year. Designing for some rare minimum or maximum temperatures is not the right way to do it, but yes, one can override the proper design temperatures in Manual J software. The result of designing for extreme temperatures is that a house will have equipment with too much capacity with its higher upfront costs. It will short cycle almost always. It will lead to blasts of cold or warm air that can cause comfort complaints. And it may cause equipment to wear out sooner because of the increased number of cycles.

]]> By: Jon https://www.energyvanguard.com/blog/dont-confuse-design-temperature-with-degree-days/#comment-13975 Sun, 04 Apr 2021 13:52:26 +0000 https://energyvanguard.com/?p=5220#comment-13975 Also, never confuse “design temperature” with the min/max outdoor temperature that the system should be designed to handle. Outdoor temperature will exceed the design temperature for extended periods and you want to remain comfortable. Luckily, Manual J accounts for this difference.

]]> By: Allison Bailes https://www.energyvanguard.com/blog/dont-confuse-design-temperature-with-degree-days/#comment-13807 Sat, 20 Mar 2021 14:31:55 +0000 https://energyvanguard.com/?p=5220#comment-13807 In reply to Bryan Uhler.

Bryan, it’s also related to my personal history. I lived in Seattle for a few years in the ’80s and I now live in Atlanta.

]]> By: Bryan Uhler https://www.energyvanguard.com/blog/dont-confuse-design-temperature-with-degree-days/#comment-13806 Sat, 20 Mar 2021 14:28:34 +0000 https://energyvanguard.com/?p=5220#comment-13806 Being in Washington state, it’s serendipitous that you used Seattle as an example. Good article.

]]> By: Allison Bailes https://www.energyvanguard.com/blog/dont-confuse-design-temperature-with-degree-days/#comment-13658 Mon, 01 Mar 2021 12:29:52 +0000 https://energyvanguard.com/?p=5220#comment-13658 In reply to Brendan Jackson.

Thanks for letting me know, Brendan. We just moved our website and some of the blog URLs got changed in the process. I thought we had them all fixed, but I guess not. At least this one is fixed so you can find it now.

]]> By: Brendan Jackson https://www.energyvanguard.com/blog/dont-confuse-design-temperature-with-degree-days/#comment-13656 Mon, 01 Mar 2021 02:08:17 +0000 https://energyvanguard.com/?p=5220#comment-13656 Hi Allison,
Great article as usual. Just FYI, the link to the Celsius article seems to be broken. Your blog is a national treasure, no joke.

]]> By: JC https://www.energyvanguard.com/blog/dont-confuse-design-temperature-with-degree-days/#comment-13653 Fri, 26 Feb 2021 14:30:46 +0000 https://energyvanguard.com/?p=5220#comment-13653 Very informative Mr. Bales.

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