Steady-state analysis of a slab

The computation is executed with the following commands:

beam61t1.bat

xrm3 beam61t1.i1
xrpd beam61t1.iB
xt3s beam61t1

beam61t1.i1

;  NELEM NNOD ITED
IP   4    23   61
;  CRIT SCALE THDEF
RP 1.01   1    0.01
XY N 1:10 X 2*0 2*0.25 2*0.5 2*0.75 2*1
          Y 5*(0 0.02)
          Z 10*0
EL E 1:4 N =A 1 2 4 3 =A =B 11 13 14 12 =B
           =2A =3B =4A =6B =6A =9B
EN
EN

beam61t1.iB

;  KREST 0 KOUT INT3 NSAX NSTEPX KSU
IP   1   0   2    0   10     0    1
;  TIMS ERAL EDIF
RP   0  1e-5  0.1
MP 1 T 1 V 20 0
IV 1 T 5 V 0 0.1
LV 1 T 1 I 1 V 30 10 V 2*-20 ; x = 0 m, To = -20 °C
LV 2 T 1 I 1 V 30 10 V 2*25  ; x = 1 m, To =  25 °C
AV 1 T 6 N 1 0 0 V 4*0       ; KAPPR
GV 1 T 1 V 46*25             ; initial estimate

AS 1 /M 1 /A 1 /G 1
  /L 1 E 1 L1
  /L 2 E 4 L3

EN
EN

beam61t1.STR

#    1    0.00000E+00
$TEMPERATURE
      1 -0.1182E+02  0.0000E+00  0.0000E+00
      2 -0.1182E+02  0.0000E+00  0.0000E+00
      3 -0.8750E+01  0.0000E+00  0.0000E+00
      4 -0.8750E+01  0.0000E+00  0.0000E+00
      5 -0.5682E+01  0.0000E+00  0.0000E+00
      6 -0.5682E+01  0.0000E+00  0.0000E+00
      7 -0.2614E+01  0.0000E+00  0.0000E+00
      8 -0.2614E+01  0.0000E+00  0.0000E+00
      9  0.4545E+00  0.0000E+00  0.0000E+00
     10  0.4545E+00  0.0000E+00  0.0000E+00
     11 -0.1182E+02  0.0000E+00  0.0000E+00
     12 -0.1028E+02  0.0000E+00  0.0000E+00
     13 -0.1028E+02  0.0000E+00  0.0000E+00
     14 -0.8750E+01  0.0000E+00  0.0000E+00
     15 -0.7216E+01  0.0000E+00  0.0000E+00
     16 -0.7216E+01  0.0000E+00  0.0000E+00
     17 -0.5682E+01  0.0000E+00  0.0000E+00
     18 -0.4148E+01  0.0000E+00  0.0000E+00
     19 -0.4148E+01  0.0000E+00  0.0000E+00
     20 -0.2614E+01  0.0000E+00  0.0000E+00
     21 -0.1080E+01  0.0000E+00  0.0000E+00
     22 -0.1080E+01  0.0000E+00  0.0000E+00
     23  0.4545E+00  0.0000E+00  0.0000E+00