Indoor is always higher ppm (how much depends on many parameters) without proper ventilation. „Proper“ should include a „Heat exchanger“ thus you don’t need to reheat fresh air.
Still, it will add some 80ppm over the amount you have today. There's a huge amount of disagreement over how much CO2 is harmful, but it tends to happen over numbers way above 800ppm.
If your room has 2 times the open air concentration, and you are concerned if it's 2.0 times or 2.2 times, you should already be dealing with the problem.
marcosdumay|2 months ago
If your room has 2 times the open air concentration, and you are concerned if it's 2.0 times or 2.2 times, you should already be dealing with the problem.
literalAardvark|2 months ago
So at 500 external you'd pretty much need continuous ERV but not necessarily scrubbers just yet.