diff --git a/code/modules/atmospherics/machinery/components/unary_devices/passive_vent.dm b/code/modules/atmospherics/machinery/components/unary_devices/passive_vent.dm
index 94d8959987..d1daa720ca 100644
--- a/code/modules/atmospherics/machinery/components/unary_devices/passive_vent.dm
+++ b/code/modules/atmospherics/machinery/components/unary_devices/passive_vent.dm
@@ -20,28 +20,36 @@
 /obj/machinery/atmospherics/components/unary/passive_vent/process_atmos()
 	..()
 
-	var/datum/gas_mixture/environment = loc.return_air()
-	var/environment_pressure = environment.return_pressure()
-	var/pressure_delta = abs(environment_pressure - airs[1].return_pressure())
+	var/active = FALSE
 
-	if((environment.temperature || airs[1].temperature) && pressure_delta > 0.5)
-		if(environment_pressure < airs[1].return_pressure())
-			var/air_temperature = (environment.temperature > 0) ? environment.temperature : airs[1].temperature
-			var/transfer_moles = (pressure_delta * environment.volume) / (air_temperature * R_IDEAL_GAS_EQUATION)
-			var/datum/gas_mixture/removed = airs[1].remove(transfer_moles)
-			loc.assume_air(removed)
-			air_update_turf()
+	var/datum/gas_mixture/external = loc.return_air()
+	var/datum/gas_mixture/internal = airs[1]
+	var/external_pressure = external.return_pressure()
+	var/internal_pressure = internal.return_pressure()
+	var/pressure_delta = abs(external_pressure - internal_pressure)
+
+	if(pressure_delta > 0.5)
+		if(external_pressure < internal_pressure)
+			var/air_temperature = (external.temperature > 0) ? external.temperature : internal.temperature
+			var/transfer_moles = (pressure_delta * external.volume) / (air_temperature * R_IDEAL_GAS_EQUATION)
+			var/datum/gas_mixture/removed = internal.remove(transfer_moles)
+			external.merge(removed)
 		else
-			var/air_temperature = (airs[1].temperature > 0) ? airs[1].temperature : environment.temperature
-			var/output_volume = airs[1].volume
-			var/transfer_moles = (pressure_delta * output_volume) / (air_temperature * R_IDEAL_GAS_EQUATION)
-			transfer_moles = min(transfer_moles, environment.total_moles()*airs[1].volume/environment.volume)
-			var/datum/gas_mixture/removed = loc.remove_air(transfer_moles)
+			var/air_temperature = (internal.temperature > 0) ? internal.temperature : external.temperature
+			var/transfer_moles = (pressure_delta * internal.volume) / (air_temperature * R_IDEAL_GAS_EQUATION)
+			transfer_moles = min(transfer_moles, external.total_moles() * internal.volume / external.volume)
+			var/datum/gas_mixture/removed = external.remove(transfer_moles)
 			if(isnull(removed))
 				return
-			airs[1].merge(removed)
-			air_update_turf()
-	update_parents()
+			internal.merge(removed)
+
+		active = TRUE
+
+	active = internal.temperature_share(external, OPEN_HEAT_TRANSFER_COEFFICIENT) ? TRUE : active
+
+	if(active)
+		air_update_turf()
+		update_parents()
 
 /obj/machinery/atmospherics/components/unary/passive_vent/can_crawl_through()
 	return TRUE