diff --git a/HARDWARE/PID.c b/HARDWARE/PID.c
index cc11033..b621730 100644
--- a/HARDWARE/PID.c
+++ b/HARDWARE/PID.c
@@ -261,7 +261,7 @@ void PID_Calc() // pid calc
 	} else {
 		// if outer temp is got, we calc pid by outer temp
 		if (abs(pid.out_tem) > 1e-5) {
-			pid.cp = (pid.out_tem - pid.set_tem) / 4.3 + 0.7;
+			pid.cp = (pid.out_tem - pid.set_tem) * 0.26 + 0.3;
 		}
 		// use nagetive error and error diff when calc compressor power
 		int p_c = calc_cp(delta_t, - Error_calc, - DelEk, pid.c_base, pid.cp, pid.ci, pid.cd);