My ventilation system failed during a 4 day test run inside my bunker last month

I sealed myself in for a trial stay and by hour 72 the CO2 levels hit 2,500 ppm and I got a splitting headache even with my battery powered fans running. Turns out my intake filter was clogged with dust from the old furnace I stored nearby. Has anyone else had their air quality crash during a longer stay?

3 comments

3 Comments

reese_lee910d ago

A solar powered vent fan with a backup battery setup saved my bunker during a similar test run. I had the same CO2 spike around hour 60 when my main fan died due to a bad connection, and the headaches hit fast. What worked was installing a cheap CO2 monitor that connects to my phone so I caught the problem early. I also swapped out my old furnace filters for high quality MERV 13 ones and check them before every seal up. Took me two failed attempts to figure out the airflow equation but now I run a small fan down low and another one up high to create a good cross breeze. The whole setup cost me under $200 and it's been solid for week long stays since then.

sethfoster10d ago

Wait, isn't that basically the same principle as how stale air gets trapped upstairs in my house in the summer? lol I never thought about it for a bunker but the high/low fan trick makes total sense for pushing that dead air out.

king.eric10d ago

Man, that's almost exactly what happened to me on my third test run last spring. I was only 48 hours in and the CO2 alarm I rigged up started screaming, felt like someone was squeezing my temples. Turned out I'd stored a bunch of old sandbags right in front of my intake vent and they'd been shedding dust for months. I ended up doing the same thing with a low fan and a high fan setup after reading about how heat rises and traps stale air near the ceiling. The cross breeze trick is a lifesaver, I run a little 12 volt computer fan up high pointing out and another one down low pulling fresh air in. Also switched to MERV 13 filters like you said and I check them every time before sealing up now, learned that lesson the hard way. That cheap CO2 monitor with phone alerts is the next thing on my list, I had to learn to listen for the alarm but a phone ping would've saved me that headache for sure.