I installed the APC Defend unit this spring https://www.arprv.com/products.php , it has fans for cooling the boiler and fans for inside refrig. It also has the added fire safety benefit of monitoring boiler temp. and will shut down boiler if it overheats ( as in operating when not level ) then restarts when temp cools down. This feature alone is worth the cost as it could save your refrig. and/or your GMC from burning to the ground
just ask Bob Donahue.
It works great,and great customer service too.
I was going to put a fire suppression system in but figured this option was much better - shuts things down BEFORE a fire starts.
just what I did