Warm heatbed lower than cold one?

I've got this printer: [construction-zone.de]
and printing was already working:
[www.upload-pictures.de]

After a flat move I have to recalibrate the printer now.
The manufacturer has some guidance here:
[construction-zone.de]

Previously with cold heatbed and hotend, and
#define Z_MAX_LENGTH 418
in the repetier arduino sketch = printer firmware I had after calibration with hot hotend and heatbed:

p1: Z: 1.68
p2: Z: 1.64
p3: Z: 1.66

0,0 Z: 1.68

p4: Z: 1.62
p5: Z: 1.58
p6: Z: 1.61

with p6 being: X-77.94 Y45 Z10 .
So this was very much ok and I was able to print well.

After a flat move I now recalibrate the printer.
There is:
#define Z_MAX_LENGTH 416.32

Now in cold mode the values are
0,0,Z: 0.11
P1 : 0.04
P2 : 0.15
P3 : 0.13
P4 : 0.00
P5 : 0.01

and when heating up to hotend 200°, heatbed 60°:
0,0,Z: 0
P1 : 0
P2 : 0,02
P3 : 0,03
P4 : 0
P5 : 0
P6 : 0

How can that be?
Shouldn't the value for a heated system be higher, something like
0,0,Z: 0,35
P1 : 0,28
P2 : 0,39
and so on?
Does that mean that my heatbed is somehow warped downward after heating up (which would be bad)?

Maybe it's just the hotend that got longer from heating? What kind of probe do you have? IR-sensor by any chance?

Quote
o_lampe
Maybe it's just the hotend that got longer from heating? What kind of probe do you have? IR-sensor by any chance?

But then the hotend would have to be shorter or the heatbed lower.
The whole thing is going further down when heated up - that's what I do not understand.
Normally if the system is heated up the heatbed extends and the hotend and the point where the hotend touches the paper moves up, that was always the case.

(I do not have an IR sensor, I just use the normal paper method and read what repetier host says)

Otoh I was able to print normally.
I just want to understand this and avoid e.g. the heatbed "popping up" suddenly and making the hotend scratch on the Kapton tape.

You can heat the parts individually and use a feeler gauge to measure the Gap in different places on the bed. For instance heat the hot end only and measure the gap. Then let it cool and hit the bed only and measure the gap in multiple places