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How does outdoor temperature affect indoor temperature.

Theoretically outdoor temperature dictates indoor temperature. But there is probably a delay. A building should be able to keep its indoor temperature for some time, if insulated at all. Can we see what delay it is?

The delay is probably not constant, as it is also influenced by wind (windchill effect), changes in athmospheric pressure (air tries to move either in or out) and intensity of sunlight (sun shining through window influences room temperature).… Read the rest


Permafrost. Or is it?

How cold it gets under the ground, when ground source heatpump sucks out all the heat? Will the ground freeze?

Probably the answer is ‘depends’. I have heard anectotal evidence from ground source heatpump installers, that they had to dig out too short pipes from underground, during summer, where it was just a big frozen lump.… Read the rest


Heatpump Adventure

Actually not really an adventure, but I did get a ground source heatpump this spring.

While looking for it, I came up with many questions I could not really answer, or did get different answers from different sources. As time goes on, I start to forget about them, so it is about time to write them down and see, if I can get answers for those from experience.… Read the rest


Resize iSCSI partition

Lets have a practical scenario. A disk box, with iSCSI LUN, which is used by a linux box.
LUN fills up, and is resized on that disk box.

On linux side, lets rescan session, to get updated target size visible:
iscsiadm -m session -R

Lets assume, the partition is plain ext4 and available as /dev/sde1

parted /dev/sde

Parted should detect disk size update and notify about it
Warning: Not all of the space available to /dev/sde appears to be used, you can fix the GPT to use all of the space
(an extra 2147483648 blocks) or continue with the current setting?
Read the rest