Reply to item 9861421 from HPSCHD-L@CNS sent on 98/11/10 12:30
I find your slab heating situation interesting. My house has a similar
one, but the way it works is a bit different.
There are heating wires deep in the floor (concrete) which are heated
during the night because we pay half price for power from midnight to
7.00 a.m. How long it is actually on for depends only on the outside air
temperature. As we have it set, at 15C (about 50F) it cuts in and is on
for just a few seconds every five minutes. At -5C (about 25F) it is on
all the time. Since the floor is quite solid, this stores heat in the
slab for the rest of the day, but it tends to cool down a little by the
evening. There is a second set of wires in the ceilings, embedded just a
few millimeters in the plaster. This is connected to a thermostat
measuring air temperature in the same room, and allows you to fine tune
the temperature of each part of the house. Running the floor heating on
the basis of internal temperature is no good, because there is a time lag
of many hours, which is why it makes much more sense to measure the
I find that both the temperature and humidity of the attic room where I
keep the harpsichord are extremely consistent and have never given me any
problems. I like your idea of measuring the air temperature inside the
case. In my case I would do that with the ceiling heating, not the floor
heating, and it would be an excellent fine tuning system. If your
configuration is different, you might consider setting the temperature
slightly below ambient with the floor heating and add supplementary
heating of some sort for the rest.
For human beings, I agree that this heating is subjectively much more
comfortable and less stuffy than standard radiators or hot air, partly I
suspect because it affects humidity much less and also allows you to
ventilate the house better without quickly losing heat.
Barcelona, where it never gets very cold.