Re: Dilbert: Company policy against space heaters


Mark Jackson wrote:
"Blinky the Wonder Wombat" <wkharrisjr_info@xxxxxxxxx> writes:

Default User wrote:
Blinky the Wonder Wombat wrote:

There is always losses when converting from one energy form to another
(see: entropy).

The fraction of the energy converted that ends up as heat (100% in this
case) *is* what causes the increase in entropy - delta S equals (at
least) the integral of dQ/T (more for irreversable processes).


Guess I'll have to dust off the themo books tonight and brush up- of
course you are right....

The solution is not to try to warm the entire zone (which is
impractical since everyone has a different idea of what the proper
temperature should be). Ideally, if there were enough sub-zones with
individual temperature sensors and controls, you could achieve some
level of comfort. Of course, there is a big gap between theory and the
real world.

Ideal solution? Hard walled offices for everyone, or at least smaller
open areas.

I've seen space heaters several times in hard-walled offices, when the
building air handling system could not be adjusted (or the maintenance
trolls could not adjust it) to make a particular office acceptably
warm.


I agree that space heaters in hard walled offices are a good practical
solution; it's usually not worth the effort to try and fine tune a
large system for just one area.

This causes the heater to run
much longer in order to maintain the temperature in the area one
wants to keep heated. Finally, throwing heat into an area you are
trying to cool forces the cooling system to work even harder.

You've added in areas that need to be cooled, which wasn't originally
stated. The OP said:

I worked for 15 years in a building where space heaters were outlawed,
and the only heat we had was from water-driven radiators (when they
remembered to turn the things on.

Surprisingly, cooling systems in office buildings run year-round-
people and office equipment generate a lot of heat. Even in winter in
northern states, the air conditioning system has to be run or else
building temperatures will quickly rise to uncomfortable levels.

Not true in general, and in particular not true for our circa
30-year-old building complex near Rochester NY. The AC is shut down in
the fall and the heating system is shut down in the spring, both times
leaving a period when we get email alerts if unseasonable weather
threatens to make spaces too warm / cold.


Of course, there is no model that fits all situations, but I suspect
the chillers and boilers are shut down for economic reasons, not HVAC
reasons. I would venture that in the winter the chillers are turned off
and the outside air flow is kicked up to provide cooling (especially
attractive alternative in the northern states). This is a very
cost-effective way to control building temperatures, but as I am sure
you realize, not always properly followed up by the operating staff.

I don't know what summers are like in Rochester, but in areas where
humidity is a problem, the heating system should run year-round to
knock the water out of the air. (Outside and return air is cooled to
saturation temperature to drive out the moisture and then heated up to
room temperature). Of course, if humidity is not a problem, shutting
off the heat on a certain date would appease the accounting trolls....

.

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