diff --git a/code/ATMOSPHERICS/components/trinary_devices/filter.dm b/code/ATMOSPHERICS/components/trinary_devices/filter.dm
index 6a92f9a24bf..acc528e6110 100755
--- a/code/ATMOSPHERICS/components/trinary_devices/filter.dm
+++ b/code/ATMOSPHERICS/components/trinary_devices/filter.dm
@@ -62,7 +62,7 @@ Filter types:
 
 		var/output_starting_pressure = air3.return_pressure()
 
-		if(output_starting_pressure >= target_pressure)
+		if(output_starting_pressure >= target_pressure || air2.return_pressure() >= target_pressure )
 			//No need to mix if target is already full!
 			return 1