I did read the thread.
I could be wrong but the discussion is how to monitor HVAC Air Filter for when to change it.
The answer is very simple - every 3-4 month.
You would be wrong though.
That's like stating it takes 30 seconds to fill a container from a faucet. Always. In every home and business across the globe. When you don't know the size of the container, water pressure or faucet size....
You ignore environmental conditions. The actual capacity of the system. Filter rating. Runtime etc.
You seem engineering type. Consider the variables. You absolutely can quantify drop on a system. But, you don't have to if it bothers you.
No I haven't put any type of sensor in my hvac, as I never thought of monitoring for filter changes.
In short:
Theoretically air filter monitoring with diff pressure sensor definitely could be done.
However taking in account gazillions of variables (as you mentioned) this will be impractical.
1 Like
I don't think you understand it correctly or understand hvac.
Thank you very much for your feedback.
2 Likes
This article may be helpful:
There are so many considerations:
- Duct design coupled with blower motor
- Size of return
- Depth of filter (1", 2" or even larger). Deeper filters theoretically have more surface area of filter
- Rating of filter fabric (Merv rating)
- IWC rating of filter fabric, which measures the resistance at certain airflow rates. Not all MERV 13 filters have the same IWC
- Number of pleats in that MERV 13 filter. I've bought them with 11 pleats and with 62 pleats. The one with 62 pleats obviously has more filter area so all other variables being equal should theoretically last longer.
Keeping the resistance low will get better airflow in your HVAC and make your equipment last longer.
I'd like to measure this to determine if my duct design has sufficient space behind the filter grill for a 2" filter, and which filter gives me the best performance, and how long the interval between changes should be.
2 Likes
