From 7a0b5c4b96dead8652447f7f8dd63155d5e617ad Mon Sep 17 00:00:00 2001
From: Codex Agent <codex@example.com>
Date: Sat, 22 Nov 2025 18:25:23 +0100
Subject: [PATCH] Start in cold manual state with rods inserted

---
 src/reactor_sim/reactor.py | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/reactor_sim/reactor.py b/src/reactor_sim/reactor.py
index f064e9b..79592c7 100644
--- a/src/reactor_sim/reactor.py
+++ b/src/reactor_sim/reactor.py
@@ -76,6 +76,16 @@ class Reactor:
             fission_product_inventory={},
             emitted_particles={},
         )
+        # Default to a cold, safe configuration: rods fully inserted, manual control, pumps/turbines off.
+        self.control.manual_control = True
+        self.control.rod_fraction = 0.95
+        self.primary_pump_active = False
+        self.secondary_pump_active = False
+        self.turbine_unit_active = [False] * len(self.turbines)
+        self.turbine_active = any(self.turbine_unit_active)
+        if self.consumer:
+            self.consumer.set_online(False)
+
         primary = CoolantLoopState(
             temperature_in=ambient,
             temperature_out=ambient,