| WIKI | FAQ | Tech FAQ | |
 http://csua.com/feed/ | |
| ||||||
| 11/22 |
| 2006/1/23-25 [Science/GlobalWarming, Science/Electric] UID:41488 Activity:high |
1/23 In the old days there were convection heaters. There were
oil heaters, horizontal electric heaters, and heat dishes. While
they worked, they created heat spots and didn't distribute heat
evenly. Later someone had a brilliant idea of putting a fan in
the heater, and today most of the electric heaters come with
at least one fan-- usually something that blows a lot of dust
into the air, and hums loudly at night. Well, fuck the dust
and the noise. I have gone back to the good 'ol days. I just bought
a regular Holmes aluminum convection heater. It is nearly silent
and doesn't disturb me at night. Fuck modern technology. Go old
convection heaters. -I really hate new things
\_ I actually prefer the noise at night. I can't sleep in silence.
\_ Costco carries heat dishes, if you prefer heat spots and uneven
heating. I bought one.
\_ Yeah, I had one at Cal, worked awesome, mainly because of the
surface area and the principle of convection. Much better than
other heaters I've used. Saved a lot on heating bills too!
\_ I did a google search on "convection heaters", and this chart
says the fan units heat your room much faster (but are noisier)
http://tinyurl.com/7uej5 (choice.com.au)
\- I used to work on numerical and analytic models of heat
transfer to analyze things like circuit board layouts.
Obviously convection is a huge boost over mere radiation
but it turns out you also want a turbulent flow rather than
laminar for greater heat capacity/xfer, although in a wasteful
system like this, those details dont matter too much. Berkeley
Math/Mech Eng is a big place for fluid dynamics, tribology etc.
I think HILFINGR has some affilation with the people who do
some of the applied work here [e.g. COLLELA and MARCUS].
some of the applied work here [e.g. COLELLA and MARCUS].
\_ Why not get an air filter? Works great for dust. -John
\_ Please recommend a make and model. -- ulysses
\_ I don't have a specific recommendation, but a friend in the
HVAC business told me to buy filters either really cheap
or really expensive. Don't buy anything in the middle. He
said those tends to starve your system of air. Oh I am
talking about built-in home system, not the portable stuff.
\_ I had a big cylindrical one in colleage--I don't remember
the model, but it worked great. About 30" high and 20" in
diameter, with a replaceable filter that wrapped around the
inside. Worked a charm in a very dusty room. -John
\_ wear more. Thermal layers do wonders. Use less energy, save the earth
\_ Seconded. |
| 11/22 |
|
| tinyurl.com/7uej5 -> www.choice.com.au/viewArticle.aspx?id=103652&catId=100519&tid=100008&p=6 Note: This is a 2003 test report, and only a few of the tested models are still available. Brand / model (in rank order) Overall score Heating score Ease of use score Safety tests Noise Manufacturer / distributor Warranty (years) Price * DIMPLEX DX20F 75 84 54 Fell over in tilt test Medium 2 Hagemeyer 84 EWT 2577 75 84 54 Fell over in tilt test Noisier 2 Hagemeyer 99 MISTRAL MCVH2000 71 75 62 Kept heating when on its back Quieter 2 Mistral 80 OMEGA OCH2072 71 80 50 OK Noisier 2 Omega Smeg 99 GOLDAIR 8600 67 73 54 OK Noisier 1 Kambrook 90 ARLEC HC2000S 65 66 62 Quieter 1 Arlec 70 SUNAIR HC-2000 65 66 62 Fan broke in towel test; Quieter 1 GAF Control 59 ARLEC MTH1 56 47 76 Kept heating when on its back; No fan 2 Arlec 150 IXL 72405 55 49 70 Fell over in tilt test; plastic ousing damaged in towel test No fan 2 IXL Appliances 259 DeLONGHI BBH100 52 54 48 Kept heating when on its back No fan 2 Parex Industries 169 * Prices shown are recommended retail, according to manufacturer information in February 2003. Overall score This is a combination of the heating (70%) and ease of use (30%) scores. Heating score The heaters were assessed in a thermal comfort lab -- a room measuring 49 m by 35 m with an insulated ceiling (height 24 m), which sits within a temperature-controlled outer room that provides a constant outside temperature. We tested the following: * Heating speed: How long does the heater take to raise the room temperature by 5DEGC and 10DEGC? Ease of use score We assessed the following: * Use of controls. Safety tests These included a tilt test and a towel test. Noise Without the fan operating, convection heaters are very quiet. We measured the fan noise 1 m in front of the heater, and 1 m up. The noisier models in our test may impact on a conversation or TV sound. However, you're likely to use the fan only for a short period at a time - to quickly heat up your room initially, and then for a few minutes every now and then to distribute the heat evenly. So we don't think noise is a big problem with this type of heater. |