Hehe, sorry about that, HotLine.
Mind you, even the plain old resistance heaters for room heating get far more hate from the "environmentalists" than they really deserve, if you ask
me. A unit using about 1500W, that requires a whole circuit to itself at 120V (at least if you go by the seemingly grandfathered-in "80% rule"), is on 220-240V a piece of cake to deliver the power to (with even a 0.75mm˛ flexible cord staying stone cold at the resultant current, more-or-less). Nothing else can parallel the plug-and-go convenience (making them perfect for use in rooms that you only temporarily need to heat), they can run in total silence (with the obvious exception of fan heaters, but even they can be fairly quiet), and the circuit itself is a fantastic example of the KISS (Keep It Simple Stupid) design principle in action - in stark contrast to the technical nightmare that electric
cars have been, but (strangely) those are heavily promoted by the mainstream greenies. But then again, I've found it to be true surprisingly often that the more heavily pushed a supposedly "green" technology is by the mainstream, the harsher the truths behind it turn out to be...
The main reasons, however, why most people currently perceive portable electric heaters as being economically (and ecologically)
hopeless are, in my view:
- The deplorable state of mainstream buying "advice" and reviews; it might come as a surprise to most people, but in direct opposition to everything else, resistance heating elements can only have a 100% (for all practical intents and purposes) intrinsic efficiency, in accordance with the laws of thermodynamics (although I can't deny that the system efficiency, considering the losses in electricity generation and to a lesser extent transmission, still falls quite a bit shy of that). They could only be any less efficient if they destroyed energy, which isn't possible (you remember, don't you?); after all, guess what the energy "wasted" in each other device ends up as?
But the mainstream reviewers, such as Choice magazine down under, still don't get it. To quote what their current article says about them: "Good heating performance and good energy efficiency don't always go together. A model may be great at heating, but only OK for efficiency, meaning it will heat the room effectively but cost more to run. Some are efficient but only OK performers, so they don't heat the room as effectively, but at least they use less power. Sadly, we've found a few that are not only weak at heating, but use a comparatively large amount of power too..." Of course, they fail to understand that fan heaters are not meant for direct personal heating, and they also reinforce the "never-use-an-extension-cord" propaganda (more on that below)... Mind you, I pretty much know the designs of these heaters inside-out, so it would certainly be within my power to make good reviews of them once I get the needed tools. Even the otherwise great book, "Green is Good" by Rebecca Blackburn [ISBN 0-7322-8561-5], dropped the ball on the heater discussion too. So the impression most buyers are consequently left with - that models without a thermostat will be somehow "automatically" more expensive to run than those with one - has resulted in a few budget models (notably the Kambrook KFH200) that use a fixed thermostat (by way of fitting a bimetallic switch - otherwise used as the primary thermal protector in modern convection heaters - with a ridiculously low activation temperature), which renders them immediately worthless (except in fan-only mode) to be honest (that unit wouldn't even stay on when I temporarily operated it outdoors!). I usually don't bother using the adjustable thermostats myself either - I just leave them at the highest setting and manually switch between power levels as needed (which is probably easier on the elements anyway). Then there's... - ...the all-time classic of misusing fan heaters for heating just your feet; but that's not at all because they inherently suck, only because most of the heat still goes into the room. Any further warmth from being in close proximity to a convection heater (fanned or fanless) should be considered just a bonus, with heating the room itself the primary motivation. In my experience, a suitably comfortable mat (to thermally insulate your feet from the floor) works fine, with no power requirement; and if you insist, I'm sure purpose-made heating pads are out there. And last but certainly not least...
- ...the innate greed people have been conditioned by society (weird as it is) to have, which probably more than negates the advantage of reverse-cycle air conditioning (still only 3.4x or so, typically) to be realistic; not content with temperate, the general public like to run heaters powerful enough to make the room (or themselves, in the case of radiant heaters) very hot indeed. As for me, it's the middle of winter here and I still get by fine with 600W or at most 900W (the low and medium settings on, at present, an Omega Altise OMC15E1) in a decent-sized area (in a house with only ceiling insulation and without insulated glazing, to boot - although the window area here at least isn't excessive).
It doesn't help that society has
also conditioned people to reinforce their established beliefs as routine, even on topics they have zero in-depth knowledge about.
As a decent compromise between ergonomics and economics, I've taken to using the resistance heater(s) up to 1kW or so (long-term) and the air conditioners beyond that. So here's my honest run-down on the pros and cons of each form of portable heater available (past and present):
Fan heater+ thanks to forced airflow, can attain the highest common power rating (2400W @ 240V) in a small, convenient, and
very affordable form
+ doubles as a cooling fan in summer, for "free"
+
all affordable models are double-insulated, along with including dual thermal protectors
and a tip-over switch to current requirements (at least in Europe and Australasia) - how much safer
could you want them to be, really?
o moderate surface temperature (not enough to burn or melt most stuff, but may hurt small children)
- some noise from the fan, but at least it's
constant (unlike the irregular noises that many air conditioning units - my own included - make while running)
? fan bearing longevity (they may be poorly lubricated as supplied; fortunately, they
can be re-oiled, and are even self-aligning making their subsequent reinstallation child's play)
? how robust are the elements in the "ceramic" variants (ostensibly safer by making the internal temperature self-limiting, although I've established that the risk of catastrophic failure of a conventional unit up to European/Australian standards should be negligible anyway; the wire elements themselves should be extremely durable with their normal temperatures much lower than in a radiant heater)
* just verify that whichever model you do get actually
complies with the standards; their
enforcement is rather lacking at present, so sub-standard models slip through the system quite regularly (especially as, being in the lowest price category, they are hit the hardest by the relentless price wars). For starters, I would recommend strength-testing the plug pins (by grabbing them with pliers and attempting to pull them axially), and examining the interior to check that
none of the crimped connectors have the lead insulation trapped in the conductor crimp section. The trouble here, of course, is that it's not in the average Joe's power to tell the fail-safe from the inevitable fire-starter by casual examination - and house brands especially can change at any time without notice.
For some strange reason, the majority of them still have only two power levels (half and full), although some of the nicer ones do have the three provided as routine on most passive convectors. (As far as implementation is concerned, aside from the power switch itself they only need to make the elements with two different gauges of NiCr wire to provide all three power levels - easy as pie, really.)
As an aside, it's quite an embarassment to note that just about every $20 fan heater has a
far superior blade design to, and runs much quieter for the same breeze as (despite being significantly smaller than), the pair of
AU$100 (yes, that's the actual retail price Mum, with me accompanying, bought them for at the time) Dimplex GDC-DF40MC desk fans (which also had pathetic switch knobs that broke almost straightaway, still have only sleeve bearings anyway, and are
not double-insulated - and even the majority of the economical desk or pedestal fans are as well! Seems to me a
typical over-priced, under-performing, poshed-up "designer" product...) that I have.
Convection heater (old-school version, with suspended wire elements)
+ silent (except while any boost fan is running, but they usually warm up quickly enough to not really need them anyway)
+
can be double-insulated (although the majority of production models so far haven't bothered as the earth wire was cheaper than the supplementary insulation - but this situation may reverse quite soon with the rapidly rising copper prices)
+ a high-quality unit should last the longest of
all of the available heaters, by far (40+ years should be easy enough to attain, and I'd bet that
centuries wouldn't be out of the question); indeed, it may be the only appliance to top the ever-dependable external mains transformer for overall reliability.
o moderate surface temperature (same as with the fan heater)
Oil-filled column heater+ silent (except while any boost fan is running, again)
+ lower surface temperature - good for use in areas with small children, or those with otherwise weakened skin (relative to that of a healthy adult)
- long warm-up time (due to the thermal mass of the silicone oil)
- the sealed elements (like in kettles) don't age
that gracefully
Micathermic heaters+ micathermic panel heaters
do look quite elegant...
- ...not that it's really
relevant, given that resistance heaters for
fixed installation make zero sense nowadays (the 2400W ones are already perfectly capable of blowing your energy budget if used on full power constantly; is the prospect of >3500W
really that appealing to you, then? Nevermind that sub-2400W ones are also sometimes permanently installed, which is utterly pointless)
- reliability seems iffy compared to the longer-established variants
- these probably can't readily be double-insulated either
Radiant heatersI'm mentioning them specifically because they're often suggested as being more economical than the other types. Unfortunately, while I can't fault the logic behind heating just yourself instead of the room
in principle, most of the models actually obtainable are
way too powerful for that proposition to work out.
(2400W of radiant heat? Are you
crazy? I'd say closer to
300W would be more reasonable.) Anyway:
+ silent
+ low price
+ excellent at spot heating, even from a distance
o medium lifespan?
- runs very hot, presenting a serious fire hazard should flammable materials enter the vicinity (and requiring a thermosetting cord); in my view, the risk would only be worth tolerating for those on the very tightest of energy budgets (if you can even
find one of the low-powered units anymore - or restore a vintage model to safe condition, for that matter)
By the way, extension cords also work fine with any type of electric heater (including radiant heaters, as long the heater's own cord is laid out straight so that the extension cord doesn't have to come any closer to the very hot unit than necessary)
provided that they are well-made and appropriately rated for the power of the heater; the supposed dangers are
so vastly overblown (especially here in Australia where we have some of the safest extension cords in the world - as long as you avoid the
horrid little 2-way adapters with no OCP, along with their first cousins, the "piggy-back" plugs;
those are a classic result of a bureaucratic compromise "solution" gone to a hopeless extreme...) that it's an embarassment to the whole notion of safety education, to be honest. Indeed, out of interest, I took a standard 5-metre ordinary-duty 1.0mm˛ extension cord, coiled into eight (!) layers, placed on top of a pillow (for good measure), and ran the Omega Altise heater through it on high (1500W resistive = 6.25A @ 240V), and it
still stabilised at a lower temperature than the heater itself - so it appears that the safety factor to withstand being coiled up (within reason) under load is built into the standard sizes for regular extension cords (along with the appliance cords beyond 2m to the IEC standards, although I would personally prefer a more conservative 0.5m or so) anyway (and it's no great burden, really, when the cores also have to sink heat from terminals, withstand sufficient fault currents in short-circuit events, and have reasonable tensile strength). So the stern warnings about it, then, might well have arrived here by way of the (at times) over-the-top globalisation - presumably another thing we can "thank" the UL for, I dare say.
Any suggestion that a resistance heating appliance can somehow harm any computer/TV/game console/etc. on the same circuit, of course, absolutely
cannot be anything more than an urban myth; it's a near-perfect resistive (what else did you think it would be?
) load with negligible inrush, what more could you possibly ask for? I do have a portable AM/FM radio (a Panasonic RF-544 that was used at Mum's office until recently - nothing fancy, but well-built for what it is), and intimate contact with my personal computer
destroys AM reception, while being in the vicinity of the OMC15E1 is literally undetectable (except when toggling the switches, that is - but that's nothing special to these heaters) even tuned to a vacant band. Indeed, the only way in which the heater could hurt the radio is if you left the radio on top of the heater constantly, but then only by overheating it (obviously). So clearly, if even the radio works fine right next to the heater, then it's
impossible for the heater to have any effect whatsover on the PC itself (unless of course, the combination overloads the circuit, causing the power to shut off when the PC isn't prepared for it).
And I can quite clearly see the "writing on the wall" for natural gas heating (which I see for the stop-gap measure that it really is) already, given that it as well as coal power has strong campaigners against it along with impending supply crises (and that
all the electric heaters to date will still be able to seamlessly operate from the superior future electricity sources that hopefully won't take
too long to reach prime time). Of course, if you already have gas heating then you might as well continue using it, but I wouldn't recommend having it newly installed by now. Plus, flammable gases and electric works (beyond cables, anyway) in the same area just
don't make a great combination. Unfortunately, at the moment we're somewhat stuck in that situation even without having natural gas supplies, as Greenpeace (more like Green
war if you ask me) has pushed the extremely flammable R-600a refrigerant (used in the majority of new fridges now) on the grounds of its low global warming
potential compared to the fail-safe R-134a that was mostly used before (albeit introduced just a few years prior). Consequently, several refrigerators in the UK have exploded already. They may defend their actions by saying that the total number is small relative to the number of installations - but if we follow that logic, why not omit the earth wires from new appliances (of all sorts) to save on copper (which
is, unquestionably, running out now), while we're at it?
The overall risk from R-600a compared to a Class 0 appliance in good condition (including the aforementioned US/Canadian toasters) is probably about the same, realistically.
One thing
is becoming clear, at any rate: We can no longer adequately rely just on safety-testing the products as volunteered by the manufacturers beforehand, as the unscrupulous ones are perfectly willing to abuse that system to send in a sample that will easily pass the tests, then change it mid-production-run such that it doesn't comply anymore. If the regulations were
solidly enforced, few products would need to be recalled and items capable of
single-handedly bringing down the safety systems would be even rarer. But at the moment, they're far too common, as by the time attention reaches the regulators, it's too late.
So there's
definitely a need to also take random samples of the actual
retail products for re-testing.
