diff --git a/code/ATMOSPHERICS/components/binary_devices/dp_vent_pump.dm b/code/ATMOSPHERICS/components/binary_devices/dp_vent_pump.dm
index 1da0a6eb71..c31f6f92b7 100644
--- a/code/ATMOSPHERICS/components/binary_devices/dp_vent_pump.dm
+++ b/code/ATMOSPHERICS/components/binary_devices/dp_vent_pump.dm
@@ -129,7 +129,7 @@
 				var/transfer_moles = pressure_delta*output_volume/(air_temperature * R_IDEAL_GAS_EQUATION)
 				
 				//limit flow rate from turfs
-				transfer_moles = min(transfer_moles, environment.total_moles*MAX_SIPHON_FLOWRATE/environment.volume)	//group_multiplier gets divided out here
+				transfer_moles = min(transfer_moles, environment.total_moles*air2.volume/environment.volume)	//group_multiplier gets divided out here
 				
 				power_draw = pump_gas(src, environment, air2, transfer_moles, active_power_usage)