4 ms·

"It depends" If you're in an older building (leaky) with a recirculating range hood (not actually vented) then opening a window is going to improve your air. M

"It depends" If you're in an older building (leaky) with a recirculating range hood (not actually vented) then opening a window is going to improve your air. Many prewar buildings in NYC were constructed with 'overpowered' radiators by the windows with the idea that people would in winter have the windows slightly ajar to bring in clean air. In a more modern building with a tight thermal envelope (not leaky) you're not passively through cracks, etc. exchanging w/the outside world. So everything builds up. One solution is a fresh air system like an ERV or HRV which exchanges air, filters, and exchanges heat and humidity too (so an improve version of keeping the window open). My 1985 run of the mill center hall colonial is moderately leaky. If I run the bathroom fans a negative pressure environment is created and air is pulled from under the slab (which creates a radon concern, for me). I suspect this approach, slightly pressurizing every room, would work for me. But I think this is very similar to what an HRV/ERV might do anyway...

pivo 3y ago
> Many prewar buildings in NYC were constructed with 'overpowered' radiators by the windows with the idea that people would in winter have the windows slightly ajar to bring in clean air. Wow, thank you! I've always wondered why the heat seemed so unnecessarily overwhelming in radiator buildings I grew up in. We'd keep the windows open because there was no way to control the heat and I'd always thought it was such a waste of energy. Not sure how clean the outside air was at the time, but I did really miss the mix of cold and warm air in the winter when I moved to a more modern building.
- blamazon 3y ago
  One explanation for this phenomenon is that the initial rapid proliferation of 'modern' radiators in NYC happened around the same time as the 1918 influenza pandemic. It was understood that fresh air was something of an antidote. Tangentially, people wore masks as well during that global pandemic [1] and there were even anti-mask groups. [2] It makes me wonder what a pandemic a hundred years from now would be like and what physical manifestations of 2020 will remain. [1]: https://twitter.com/georgiatech/status/1307410628470956032 https://twitter.com/georgiatech/status/1307410628470956032 [2]: https://en.wikipedia.org/wiki/Anti-Mask_League_of_San_Francisco https://en.wikipedia.org/wiki/Anti-Mask_League_of_San_Franci...
ilyt 3y ago
Interesting, I always assumed the "overpowered" radiators were just to compensate relatively bad window isolation.
jaggederest 3y ago
You can set the air balance in most ERV/HRV to be positive or negative. I think the rule of thumb is that they almost always are set to provide slight positive pressure, to avoid drafting e.g. gas appliance exhaust into the house, but I'm not a HVAC expert, just someone looking into them for residential usage.

pivo 3y ago

> Many prewar buildings in NYC were constructed with 'overpowered' radiators by the windows with the idea that people would in winter have the windows slightly ajar to bring in clean air. Wow, thank you! I've always wondered why the heat seemed so unnecessarily overwhelming in radiator buildings I grew up in. We'd keep the windows open because there was no way to control the heat and I'd always thought it was such a waste of energy. Not sure how clean the outside air was at the time, but I did really miss the mix of cold and warm air in the winter when I moved to a more modern building.

blamazon 3y ago
One explanation for this phenomenon is that the initial rapid proliferation of 'modern' radiators in NYC happened around the same time as the 1918 influenza pandemic. It was understood that fresh air was something of an antidote. Tangentially, people wore masks as well during that global pandemic [1] and there were even anti-mask groups. [2] It makes me wonder what a pandemic a hundred years from now would be like and what physical manifestations of 2020 will remain. [1]: https://twitter.com/georgiatech/status/1307410628470956032 https://twitter.com/georgiatech/status/1307410628470956032 [2]: https://en.wikipedia.org/wiki/Anti-Mask_League_of_San_Francisco https://en.wikipedia.org/wiki/Anti-Mask_League_of_San_Franci...

ilyt 3y ago

Interesting, I always assumed the "overpowered" radiators were just to compensate relatively bad window isolation.

jaggederest 3y ago

You can set the air balance in most ERV/HRV to be positive or negative. I think the rule of thumb is that they almost always are set to provide slight positive pressure, to avoid drafting e.g. gas appliance exhaust into the house, but I'm not a HVAC expert, just someone looking into them for residential usage.