Device working volumes are configurable from setup

code/ATMOSPHERICS/components/binary_devices/dp_vent_pump.dm

@@ -45,6 +45,8 @@
 
 /obj/machinery/atmospherics/binary/dp_vent_pump/New()
 	..()
+	air1.volume = ATMOS_DEFAULT_VOLUME_PUMP
+	air2.volume = ATMOS_DEFAULT_VOLUME_PUMP
 	icon = null
 
 /obj/machinery/atmospherics/binary/dp_vent_pump/high_volume
@@ -52,8 +54,8 @@
 
 /obj/machinery/atmospherics/binary/dp_vent_pump/high_volume/New()
 	..()
-	air1.volume = 1000
+	air1.volume = ATMOS_DEFAULT_VOLUME_PUMP + 800
-	air2.volume = 1000
+	air2.volume = ATMOS_DEFAULT_VOLUME_PUMP + 800
 
 /obj/machinery/atmospherics/binary/dp_vent_pump/update_icon(var/safety = 0)
 	if(!check_icon_cache())

code/ATMOSPHERICS/components/binary_devices/pump.dm

@@ -36,6 +36,11 @@ Thus, the two variables affect pump operation are set in New():
 	var/id = null
 	var/datum/radio_frequency/radio_connection
 
+/obj/machinery/atmospherics/binary/pump/New()
+	..()
+	air1.volume = ATMOS_DEFAULT_VOLUME_PUMP
+	air2.volume = ATMOS_DEFAULT_VOLUME_PUMP
+
 /obj/machinery/atmospherics/binary/pump/on
 	icon_state = "map_on"
 	on = 1

code/ATMOSPHERICS/components/omni_devices/filter.dm

@@ -21,6 +21,8 @@
 /obj/machinery/atmospherics/omni/filter/New()
 	..()
 	rebuild_filtering_list()
+	for(var/datum/omni_port/P in ports)
+		P.air.volume = ATMOS_DEFAULT_VOLUME_FILTER
 
 /obj/machinery/atmospherics/omni/filter/Del()
 	input = null

code/ATMOSPHERICS/components/omni_devices/mixer.dm

@@ -45,6 +45,9 @@
 					if(tag_west_con && tag_west == 1)
 						P.concentration = tag_west_con
 						con += max(0, tag_west_con)
+	
+	for(var/datum/omni_port/P in ports)
+		P.air.volume = ATMOS_DEFAULT_VOLUME_MIXER
 
 	rebuild_mixing_inputs()
 
@@ -61,7 +64,6 @@
 			if(inputs.Find(P))
 				inputs -= P
 
-			P.air.volume = 200
 			switch(P.mode)
 				if(ATM_INPUT)
 					inputs += P
@@ -73,7 +75,7 @@
 			P.concentration = 1 / max(1, inputs.len)
 
 	if(output)
-		output.air.volume = 200 * 0.75 * inputs.len
+		output.air.volume = ATMOS_DEFAULT_VOLUME_MIXER * 0.75 * inputs.len
 		output.concentration = 1
 
 /obj/machinery/atmospherics/omni/mixer/proc/mapper_set()

code/ATMOSPHERICS/components/trinary_devices/filter.dm

@@ -12,8 +12,7 @@
 
 	var/temp = null // -- TLE
 
-	var/max_flow_rate = 200	//L/s
+	var/set_flow_rate = ATMOS_DEFAULT_VOLUME_FILTER
-	var/set_flow_rate = 200
 
 	/*
 	Filter types:
@@ -39,6 +38,10 @@
 
 /obj/machinery/atmospherics/trinary/filter/New()
 	..()
+	air1.volume = ATMOS_DEFAULT_VOLUME_FILTER
+	air2.volume = ATMOS_DEFAULT_VOLUME_FILTER
+	air3.volume = ATMOS_DEFAULT_VOLUME_FILTER
+	
 	if(radio_controller)
 		initialize()
 
@@ -217,8 +220,8 @@
 	if (href_list["temp"])
 		src.temp = null
 	if(href_list["set_flow_rate"])
-		var/new_pressure = input(usr,"Enter new flow rate (0-[max_flow_rate]L/s)","Flow Rate Control",src.set_flow_rate) as num
+		var/new_flow_rate = input(usr,"Enter new flow rate (0-[air1.volume]L/s)","Flow Rate Control",src.set_flow_rate) as num
-		src.set_flow_rate = max(0, min(max_flow_rate, new_pressure))
+		src.set_flow_rate = max(0, min(air1.volume, new_flow_rate))
 	if(href_list["power"])
 		on=!on
 	src.update_icon()

code/ATMOSPHERICS/components/trinary_devices/mixer.dm

@@ -10,8 +10,7 @@
 	idle_power_usage = 150		//internal circuitry, friction losses and stuff
 	active_power_usage = 3700	//This also doubles as a measure of how powerful the mixer is, in Watts. 3700 W ~ 5 HP
 
-	var/max_flow_rate = 200	//L/s
+	var/set_flow_rate = ATMOS_DEFAULT_VOLUME_MIXER
-	var/set_flow_rate = 200
 	var/list/mixing_inputs
 	
 	//for mapping
@@ -66,7 +65,9 @@
 
 /obj/machinery/atmospherics/trinary/mixer/New()
 	..()
-	air3.volume = 300
+	air1.volume = ATMOS_DEFAULT_VOLUME_MIXER
+	air2.volume = ATMOS_DEFAULT_VOLUME_MIXER
+	air3.volume = ATMOS_DEFAULT_VOLUME_MIXER * 1.5
 
 /obj/machinery/atmospherics/trinary/mixer/process()
 	..()
@@ -162,6 +163,7 @@
 	if(href_list["power"])
 		on = !on
 	if(href_list["set_press"])
+		var/max_flow_rate = min(air1.volume, air2.volume)
 		var/new_flow_rate = input(usr,"Enter new flow rate limit (0-[max_flow_rate]L/s)","Flow Rate Control",src.set_flow_rate) as num
 		src.set_flow_rate = max(0, min(max_flow_rate, new_flow_rate))
 	if(href_list["node1_c"])

code/ATMOSPHERICS/components/unary/vent_pump.dm

@@ -62,6 +62,9 @@
 	icon_state = "map_vent_in"
 
 /obj/machinery/atmospherics/unary/vent_pump/New()
+	..()
+	air_contents.volume = ATMOS_DEFAULT_VOLUME_PUMP
+	
 	icon = null
 	initial_loc = get_area(loc)
 	if (initial_loc.master)
@@ -73,7 +76,6 @@
 	if(ticker && ticker.current_state == 3)//if the game is running
 		src.initialize()
 		src.broadcast_status()
-	..()
 
 /obj/machinery/atmospherics/unary/vent_pump/high_volume
 	name = "Large Air Vent"
@@ -81,7 +83,7 @@
 
 /obj/machinery/atmospherics/unary/vent_pump/high_volume/New()
 	..()
-	air_contents.volume = 1000
+	air_contents.volume = ATMOS_DEFAULT_VOLUME_PUMP + 800
 
 /obj/machinery/atmospherics/unary/vent_pump/update_icon(var/safety = 0)
 	if(!check_icon_cache())

code/ATMOSPHERICS/components/unary/vent_scrubber.dm

@@ -26,6 +26,9 @@
 	var/radio_filter_in
 
 /obj/machinery/atmospherics/unary/vent_scrubber/New()
+	..()
+	air_contents.volume = ATMOS_DEFAULT_VOLUME_FILTER
+	
 	icon = null
 	initial_loc = get_area(loc)
 	if (initial_loc.master)
@@ -37,7 +40,6 @@
 	if(ticker && ticker.current_state == 3)//if the game is running
 		src.initialize()
 		src.broadcast_status()
-	..()
 
 /obj/machinery/atmospherics/unary/vent_scrubber/update_icon(var/safety = 0)
 	if(!check_icon_cache())

code/ATMOSPHERICS/pipes.dm

@@ -138,7 +138,7 @@
 	name = "pipe"
 	desc = "A one meter section of regular pipe"
 
-	volume = 70
+	volume = ATMOS_DEFAULT_VOLUME_PIPE
 
 	dir = SOUTH
 	initialize_directions = SOUTH|NORTH
@@ -373,7 +373,7 @@
 	name = "pipe manifold"
 	desc = "A manifold composed of regular pipes"
 
-	volume = 105
+	volume = ATMOS_DEFAULT_VOLUME_PIPE * 1.5
 
 	dir = SOUTH
 	initialize_directions = EAST|NORTH|WEST
@@ -583,7 +583,7 @@
 	name = "4-way pipe manifold"
 	desc = "A manifold composed of regular pipes"
 
-	volume = 140
+	volume = ATMOS_DEFAULT_VOLUME_PIPE * 2
 
 	dir = SOUTH
 	initialize_directions = NORTH|SOUTH|EAST|WEST

code/setup.dm

@@ -836,10 +836,16 @@ var/list/RESTRICTED_CAMERA_NETWORKS = list( //Those networks can only be accesse
 #define MAX_FILTER_FLOWRATE	200		//L/s
 
 //These balance how easy or hard it is to create huge pressure gradients with pumps and filters. Lower values means it takes longer to create large pressures differences. 
-//If you want to limit the ability of players to create very high pressures then it makes more sense to adjust these instead of artificially limiting the pump settings. 
 //Has no effect on pumping gasses from high pressure to low, only from low to high. Must be between 0 and 1.
 #define ATMOS_PUMP_EFFICIENCY	0.6
 #define ATMOS_FILTER_EFFICIENCY	0.45
 
-#define MINUMUM_MOLES_TO_PUMP	0.01	//will not bother pumping or filtering if the gas source as fewer than this amount of moles, to help with performance.
+//will not bother pumping or filtering if the gas source as fewer than this amount of moles, to help with performance.
+#define MINUMUM_MOLES_TO_PUMP	0.01
 #define MINUMUM_MOLES_TO_FILTER	0.1
+
+//The flow rate/effectiveness of various atmos devices is limited by their internal volume, so these will control maximum flow rates in L/s
+#define ATMOS_DEFAULT_VOLUME_PUMP	200	//L
+#define ATMOS_DEFAULT_VOLUME_FILTER	200	//L
+#define ATMOS_DEFAULT_VOLUME_MIXER	200	//L
+#define ATMOS_DEFAULT_VOLUME_PIPE	70	//L