diff --git a/emulator/render-bridge/pod_render_bal.conf b/emulator/render-bridge/pod_render_bal.conf
new file mode 100644
index 00000000..f4d44dc3
--- /dev/null
+++ b/emulator/render-bridge/pod_render_bal.conf
@@ -0,0 +1,85 @@
+# pod_render_norio.conf -- pod_render_rec with the RIO serial port OFF.
+#
+# The emulator log shows a steady stream of serial1 RX OVERRUN errors on
+# the RIO pipe, and controls post their events at HighEventPriority
+# UNCONDITIONALLY (CONTROLS.HPP:250) -- so a chattering RIO port would
+# flood a priority the background pump always serves first, starving the
+# priority-0 renderer events the load gate waits on.  This conf tests that
+# by removing the port entirely.  Everything else is identical to the rec
+# conf, so a launch here and a hang there isolates the RIO.
+#
+[sdl]
+output=opengl
+# higher,higher not highest: HIGH_PRIORITY_CLASS starved the host desktop;
+# with the retry patches a rare dropout self-recovers (see gauge_rio.conf).
+priority=higher,higher
+[dosbox]
+memsize=32
+machine=svga_s3
+[cpu]
+core=dynamic
+cputype=pentium
+cycles=max
+[sblaster]
+sbtype=sb16
+sbbase=220
+irq=5
+dma=1
+hdma=5
+[mixer]
+# match the EMU8000s' native rate (no resample) and buffer ~60ms so brief
+# emulation-thread stalls (RIO retry recovery) don't audibly chop
+rate=44100
+blocksize=1024
+prebuffer=60
+[serial]
+# RIO on COM1 with the low-latency options (rxpollus/rxburst) so the board's
+# few-ms ACK deadline is met; plasma display on COM2 (real pod has both).
+# VWE fork namedpipe backend (com0com/realport retired -- COM1/COM2 gone):
+# DOSBox = pipe client (retry), vRIO/vPLASMA apps = servers; an unconnected
+# pipe behaves as an unplugged cable so the mission still runs. serialnamedpipe.h
+serial1=disabled
+serial2=namedpipe pipe:vplasma
+# live UNBUFFERED game output: DOS char devices are not buffered, so
+# redirecting stdout to COM3 lands every line immediately.  A normal
+# '> file' redirect stays 0 bytes until the process exits, which hides
+# all progress on a run that does NOT crash.
+serial3=file file:C:\VWE\TeslaRel410\emulator\render-bridge\podlog.txt
+[autoexec]
+mount c "C:\VWE\TeslaRel410\ALPHA_1"
+c:
+cd \REL410\BT
+set VIDEOFORMAT=svga
+rem production pod card init (PARAMETR.BAT:181-186): DIAGNOSE + AWEUTIL per
+rem card -- AWEUTIL /S does the EMU8000 bring-up and DRAM detect the HMI SOS
+rem driver relies on; skipping it left the cards uninitialized (silent).
+rem aweutil /s SKIPPED for now: it verifies the AWE32 GM ROM, which the
+rem emulated cards lack (hangs in a retry loop) -- restore once the ROM is
+rem dumped from a real card. diagnose /s kept (passes, sets mixer config).
+set BLASTER=A220 I5 D1 H5 P330 T6
+c:\sb16\diagnose /s
+set BLASTER=A240 I7 D3 H6 P300 T6
+c:\sb16\diagnose /s
+set BLASTER=A220 I5 D1 H5 P330 T6
+set TEMP=c:\
+rem arena1 city mission (TESTARN.EGG: map=arena1, time=day) with the RIO
+rem attached; stdout redirected so mission-load progress survives kills.
+set BT_JOINTS=1
+set L4VIEWEXT=1
+set BT_STACK_LOG=1
+set BT_MECH_LOG=1
+set BT_PRESS_BALANCE=1
+set BT_GAUGE_LOG=1
+set BT_FORCE_THROTTLE=0
+set BT_FORCE_TURN=0
+set HEAPSIZE=15000000
+set L4GAUGE=640x480x16
+call setenv.bat r s n p
+32rtm.exe -x
+BTL4REC.EXE -egg testarn.egg > COM3
+
+echo GAME-RC=%errorlevel% >> RC.TXT
+32rtm.exe -u
+echo ALPHA1-RUN-DONE
+pause
+
diff --git a/restoration/source410/BT/HEAT.CPP b/restoration/source410/BT/HEAT.CPP
index 66b1ae55..128c36a7 100644
--- a/restoration/source410/BT/HEAT.CPP
+++ b/restoration/source410/BT/HEAT.CPP
@@ -101,6 +101,14 @@ HeatableSubsystem::HeatableSubsystem(
 {
 	Check(owner);
 	Check_Pointer(subsystem_resource);
+
+	//
+	// The balance alarm arms once at birth (binary ctor @004ae568:
+	// FUN_0041b9ec(+0x1dc, 3)); the priority/share rest state rides
+	// ResetToInitialState below.
+	//
+	balanceAlarm.Initialize(3);
+
 	ResetToInitialState();
 	Check_Fpu();
 }
@@ -123,6 +131,14 @@ void
 	Check(this);
 	currentTemperature	= 300.0f;
 	heatLoad			= 0.0f;
+
+	//
+	// Binary rest state (@004ae568 ctor / the @004ae4d8-family reset):
+	// priority 1 (the equal split), share 0 until the owning mech's
+	// redistribute computes the first real fractions.
+	//
+	coolantPriority		= 1;
+	coolantShare		= 0.0f;
 }
 
 //
diff --git a/restoration/source410/BT/HEAT.HPP b/restoration/source410/BT/HEAT.HPP
index d5f1aa56..fedc6486 100644
--- a/restoration/source410/BT/HEAT.HPP
+++ b/restoration/source410/BT/HEAT.HPP
@@ -122,6 +122,27 @@
 			CurrentTemperatureOf()
 				{ Check(this); return currentTemperature; }
 
+	//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+	// The coolant-allocation trio (binary heatable +0x1d0/+0x15c/+0x1dc,
+	// ctor @004ae568).  PUBLIC: the owning Mech's redistribute walks the
+	// heatable chain and writes all three (the duckCommand precedent).
+	//
+	//   coolantPriority  the draw-weight rung, born 1; the per-subsystem
+	//       priority button (@004ae464, id TBD) steps it 0 -> 1 -> 5 ->
+	//       50 -> 0, and the mech's BalanceCoolant (0x16) resets every
+	//       heatable to 1 (the equal split).
+	//   coolantShare     priority / total, written ONLY by the mech's
+	//       RedistributeCoolantShares (@0049f788); the reservoir draw
+	//       (@004aefa4) weights each heatable's coolant feed by it.
+	//   balanceAlarm     3 levels (binary FUN_0041b9ec(+0x1dc, 3)); the
+	//       redistribute blips it -- 2 = share shrank or held, 1 = grew,
+	//       then back to 0 -- the cockpit gauge flash.
+	//
+	public:
+		int				coolantPriority;
+		Scalar			coolantShare;
+		AlarmIndicator	balanceAlarm;
+
 	protected:
 		Scalar	currentTemperature;
 		Scalar	heatLoad;
diff --git a/restoration/source410/BT/MECH.CPP b/restoration/source410/BT/MECH.CPP
index dd544bbe..70bd390e 100644
--- a/restoration/source410/BT/MECH.CPP
+++ b/restoration/source410/BT/MECH.CPP
@@ -90,6 +90,7 @@ const Receiver::HandlerEntry
 	MESSAGE_ENTRY(Mech, RealMaxSpeed),
 	MESSAGE_ENTRY(Mech, SetBurningState),
 	MESSAGE_ENTRY(Mech, ClearBurningState),
+	MESSAGE_ENTRY(Mech, BalanceCoolant),
 	MESSAGE_ENTRY(Mech, DuckRequest)
 };
 
@@ -551,6 +552,31 @@ Mech::Mech(
 		}
 	}
 
+	//
+	//-----------------------------------------------------------------------
+	// THE HEATABLE CHAIN (binary ctor sweep, part_012.c:15774: every roster
+	// subsystem derived from HeatableSubsystem -- GUID 0x50e4fc -- joins the
+	// mech+0x7cc chain), then the first coolant shares (the binary calls the
+	// redistribute at the very ctor end, after the "Mechs" group add; the
+	// ordering between is inert).  The weapon (+0x7bc) and Myomers (+0x7ac)
+	// sweeps land with their consumers.
+	//-----------------------------------------------------------------------
+	//
+	{
+		for (int hs = 2; hs < subsystemCount; ++hs)
+		{
+			if (
+				subsystemArray[hs] != NULL &&
+				subsystemArray[hs]->IsDerivedFrom(
+					HeatableSubsystem::ClassDerivations)
+			)
+			{
+				heatableSubsystems.Add(subsystemArray[hs]);
+			}
+		}
+	}
+	RedistributeCoolantShares();
+
 	//
 	//-----------------------------------------------------------------------
 	// Source the authentic per-mech locomotion params from the GameModel
@@ -925,6 +951,87 @@ void
 	AlwaysExecute();
 }
 
+//
+//#############################################################################
+// BalanceCoolantMessageHandler -- binary @0049f728 (authentic name from the
+// handler table).  A positive press resets every heatable's coolant
+// priority to 1 -- the equal split -- and renormalizes the shares.
+//#############################################################################
+//
+void
+	Mech::BalanceCoolantMessageHandler(Receiver::Message *message)
+{
+	Check(this);
+	Check_Pointer(message);
+
+	if (((int *)(message + 1))[0] > 0)
+	{
+		ChainIteratorOf<Subsystem*> mark_walk(heatableSubsystems);
+		HeatableSubsystem *heatable;
+		while ((heatable = (HeatableSubsystem *)mark_walk.ReadAndNext()) != NULL)
+		{
+			heatable->coolantPriority = 1;
+		}
+		RedistributeCoolantShares();
+	}
+}
+
+//
+//#############################################################################
+// RedistributeCoolantShares -- binary @0049f788: total the priorities, give
+// each heatable share = priority / total (0.0 when the total is empty --
+// the data word @0049f850), blip its balance alarm with the direction
+// (2 = shrank or held, 1 = grew, then back to 0), store the share.  The
+// reservoir draw weights each heatable's coolant feed by the share.
+//#############################################################################
+//
+void
+	Mech::RedistributeCoolantShares()
+{
+	Check(this);
+
+	int total = 0;
+	{
+		ChainIteratorOf<Subsystem*> sum_walk(heatableSubsystems);
+		HeatableSubsystem *heatable;
+		while ((heatable = (HeatableSubsystem *)sum_walk.ReadAndNext()) != NULL)
+		{
+			total += heatable->coolantPriority;
+		}
+	}
+
+	int share_count = 0;
+	Scalar first_share = 0.0f;
+
+	ChainIteratorOf<Subsystem*> share_walk(heatableSubsystems);
+	HeatableSubsystem *heatable;
+	while ((heatable = (HeatableSubsystem *)share_walk.ReadAndNext()) != NULL)
+	{
+		Scalar share = 0.0f;
+		if (total > 0)
+		{
+			share = (Scalar)heatable->coolantPriority / (Scalar)total;
+		}
+		heatable->balanceAlarm.SetLevel(
+			(share <= heatable->coolantShare) ? 2 : 1);
+		heatable->coolantShare = share;
+		heatable->balanceAlarm.SetLevel(0);
+
+		if (share_count == 0)
+		{
+			first_share = share;
+		}
+		++share_count;
+	}
+
+	if (getenv("BT_MECH_LOG"))
+	{
+		DEBUG_STREAM << "[coolant] shares renormalized: " << share_count
+			<< " heatables, total priority " << total
+			<< ", first share " << first_share << endl << flush;
+	}
+}
+
 //
 //#############################################################################
 // The collision-volume swap (binaries @004ac04c / @004ac064): write the
@@ -1371,6 +1478,12 @@ void
 		}
 	}
 
+	//
+	// The binary Reset (@0049fb74 tail) renormalizes the coolant shares
+	// after the roster's per-subsystem resets restored every priority.
+	//
+	RedistributeCoolantShares();
+
 	SetPreRunFlag();
 
 	if (getenv("BT_MECH_LOG"))
@@ -2169,6 +2282,19 @@ void
 				}
 			}
 			//
+			// BT_PRESS_BALANCE: one mech-level BalanceCoolant press (0x16)
+			// through the normal dispatch -- the equal-split button.
+			//
+			if (getenv("BT_PRESS_BALANCE"))
+			{
+				ReceiverDataMessageOf<int> balance_press(
+					Mech::BalanceCoolantMessageID,
+					sizeof(ReceiverDataMessageOf<int>),
+					1
+				);
+				Dispatch(&balance_press);
+			}
+			//
 			// BT_PRESS_GEN=1..4: SelectGenerator<N> at the first Emitter
 			// (the generator panel re-tap); BT_PRESS_SEEK: ToggleSeekVoltage
 			// at the first Emitter (the seek dial).
diff --git a/restoration/source410/BT/MECH.HPP b/restoration/source410/BT/MECH.HPP
index 1ff405e0..bbb3b095 100644
--- a/restoration/source410/BT/MECH.HPP
+++ b/restoration/source410/BT/MECH.HPP
@@ -980,6 +980,18 @@
 			SetBurningStateMessageHandler(Receiver::Message *message);
 		void
 			ClearBurningStateMessageHandler(Receiver::Message *message);
+		void
+			BalanceCoolantMessageHandler(Receiver::Message *message);
+
+		//
+		// The coolant-share renormalizer (binary @0049f788): share =
+		// priority / total across the heatable chain, blipping each
+		// heatable's balance alarm with the change direction.  Callers in
+		// the binary: the 0x16 handler, the ctor tail, Reset, and the
+		// per-subsystem priority stepper (@004ae464, not yet landed).
+		//
+		void
+			RedistributeCoolantShares();
 		void
 			SetStandingCollisionVolume();	// binary @004ac04c... see .CPP
 		void
diff --git a/restoration/source410/BT/MECH4.NOTES.md b/restoration/source410/BT/MECH4.NOTES.md
index ed8ed5b9..0134973d 100644
--- a/restoration/source410/BT/MECH4.NOTES.md
+++ b/restoration/source410/BT/MECH4.NOTES.md
@@ -299,26 +299,20 @@ simulationFlags bit 1 == DontExecuteFlag (SIMULATE.HPP) -- the binary's
 
 Still to land from the roster:
 
-* **BalanceCoolant @0049f728** (decoded): if payload > 0, mark item+0x1d0=1
-  across the mech+0x7cc roster, then the redistribute pass @0049f788: total
-  the marks, per item fraction = mark/total (0.0 @0049f850 when empty),
-  blip the item's alarm at +0x1dc (level 2 if fraction <= stored else 1,
-  then 0 -- the gauge flash), store fraction at item+0x15c.  UNBLOCKED (same sitting): the ctor's chain sweeps
-  (part_012.c:15760..) pin the triple by derivation GUID, names resolved
-  by static-layout adjacency to each TU's string pool: **+0x7ac =
-  MYOMERS** (GUID 0x51155c, string @0x51166d -- so the mobility scale IS
-  max leg-muscle effectiveness, item+0x31c), **+0x7bc = MECHWEAPON
-  roster** (0x511830; the ctor ORs weapon+0x334 mappable-button masks
-  into mech+0x410 as it fills it), **+0x7cc = HEATABLE SUBSYSTEMS**
-  (0x50e4fc == our heatableSubsystems chain; 0x50e604 = the HeatSink-side
-  derivation whose members get a post-ctor vcall+0x38 -- the conduction
-  link resolve).  BalanceCoolant therefore marks EVERY heatable (+0x1d0),
-  and the stored fraction +0x15c is the item's coolant ALLOCATION SHARE:
-  the reservoir draw @004aefa4 weights each item's draw by it
-  (rate = -(reservoir+0x224) x share x dt, clamped, with mass/capacity
-  bookkeeping at item+0x12c/+0x128).  Land as: three HeatableSubsystem
-  members (balanceMark/coolantShare/balanceAlarm, +0x1d0/+0x15c/+0x1dc)
-  + the handler on heatableSubsystems.
+* **BalanceCoolant @0049f728 -- LANDED 5.3.123** (equal-split press +
+  RedistributeCoolantShares @0049f788 + the heatable ctor sweep that
+  populates the heatableSubsystems chain + ctor/Reset redistribute calls;
+  soak: 20 heatables, first share 0.05, ctor + BT_PRESS_BALANCE both
+  renormalize, crash-sig 0).  UNIFICATION OWED (5.3.124): the binary's
+  MoveValve handler is @004ae464 registered on the HEATABLE base (the
+  0x50e534 name table in the heatable statics region), novice-locked via
+  mapper+0x274 == 0 (FUN_004ac9c8 -- our NoviceLockout is correct),
+  stepping heatable+0x1d0 through 0 -> 1 -> 5 -> 50 -> 0 then calling the
+  MECH redistribute -- i.e. our Condenser::MoveValve / RecomputeValves /
+  valveState triple is the SAME mechanism scoped to condensers only;
+  retire it onto coolantPriority/RedistributeCoolantShares and re-home
+  the handler on HeatableSubsystem (ValveSetting attribute retargets to
+  the share/priority cells).
 * **EjectPilot @0049f854** (head read): gated on payload > 0 AND
   **mech+0x414** -- THE EFFECTIVENESS-CENSUS CONSUMER FOUND: you can only
   eject a CRIPPLED mech (@0049fa1c's weapons/coolant/generator/limp