Pro/Forums - View Single Post - What (else) to do with heat exchanger knowledge

bobkoure · 02-02-2010, 08:00 AM

I've been looking at heat recovery ventilators lately.
These are basically an air-to-air heat exchanger with inside-house air flowing out and outside air flowing in. Because some heat is transferred from the outgoing air to the incoming air, you're not throwing away all the energy you used in heating (or cooling) inside air.
But you still get some ventilation. Turns out, most modern homes need more ventilation than they've got. What with "cash for caulkers", it's going to end up being a lot more homes than that.

Why mention it at PC? Well, firstly, there's a good deal of knowledge about airflow here. Secondly, we're a bunch of hobbyists who are already thinking about heat exchange and building things out of sheet metal. (BTW, it looks like HRVs are pretty simple to build from sheet stock). The current HRVs out there don't seem to be all that efficient (hard to get numbers, which is often a sign that they're not spectacular) so there's room for a hobbyist to make a breakthrouh - sort of like PCs and cooling, say, ten years ago.
Not as sexy as having the fastest (or the quietest) PC on the planet, but possibly interesting to some folks here.
Did I mention that there's a market for these things? If you figure out how to build one that's cheaper or smaller or more efficient, there may be a business in it for you.

IMO the limit to a2a exchanger efficiency is the airflow boundary layer. Maybe a decent place to start tinkering...

02-02-2010, 08:00 AM	#1
bobkoure Cooling Savant Join Date: Feb 2003 Location: USA - Boston area Posts: 798	What (else) to do with heat exchanger knowledge I've been looking at heat recovery ventilators lately. These are basically an air-to-air heat exchanger with inside-house air flowing out and outside air flowing in. Because some heat is transferred from the outgoing air to the incoming air, you're not throwing away all the energy you used in heating (or cooling) inside air. But you still get some ventilation. Turns out, most modern homes need more ventilation than they've got. What with "cash for caulkers", it's going to end up being a lot more homes than that. Why mention it at PC? Well, firstly, there's a good deal of knowledge about airflow here. Secondly, we're a bunch of hobbyists who are already thinking about heat exchange and building things out of sheet metal. (BTW, it looks like HRVs are pretty simple to build from sheet stock). The current HRVs out there don't seem to be all that efficient (hard to get numbers, which is often a sign that they're not spectacular) so there's room for a hobbyist to make a breakthrouh - sort of like PCs and cooling, say, ten years ago. Not as sexy as having the fastest (or the quietest) PC on the planet, but possibly interesting to some folks here. Did I mention that there's a market for these things? If you figure out how to build one that's cheaper or smaller or more efficient, there may be a business in it for you. IMO the limit to a2a exchanger efficiency is the airflow boundary layer. Maybe a decent place to start tinkering...