Infrared radiant heat from these parabolic dish heaters does NOT heat ROOM AIR much at all! It heats primarily water, things saturated with water (like we Humans), and coincidentally many Plastics---all assuming a narrow infrared focus range peaking at 3 microns (3000nm wavelength). Even longer wavelengths (3-10 microns) are possible but less specifically-aimed at human bodies and thus put heat into nearby concrete, wood floors, people, and most other materials, including many metals.
*Directional Infrared Heat* (i.e., focused Radiant Heat from these dish heaters) is VERY EFFICIENT if your goal is to put all/most of the heater's energy into YOU and not into a large room's air (or outdoor air).
BUT, this means you have to stand IN FRONT of the heater :) Otherwise, you'll barely notice much heat at all (just the small fraction of heat that escapes via convection into the air, or the wavelength falloff range that extends sufficiently to radiantly heat concrete, wood, rocks, plastics, metals, etc.
IF you use regular forced-air heaters (often the same tungsten filaments found in cheaper radiant dish heaters, nearly all quartz heaters, and heat lamps) you'll be heating most everything via convection through the air which means the larger the room and more objects to heat the more the heater's energy must be divided. That is, 500 watts of directional radiant heat will feel MUCH hotter to someone standing in front of the parabolic dish heater than would standing in front of a forced-air 500 watt heater due to air turbulence and molecules that don't have the opportunity to conduct by colliding into you (think of convection as touch-conduction in a fluid medium where each molecule of air/water/fluid is an individual messenger or heat carrier that drops off/transfers some heat to each thing it bumps into). However, you needn't stand in front of a forced-air heater vs a dish radiant one, but if you don't then the same watt forced-air heater will take a loooong time before you start feeling warm.
Most Metals Reflect Infrared wavelengths similar to a household mirror, which is why a parabolic dish heater's thin metal dish won't feel hot on its backside unless ran for extended lengths of time where convection and the non-100% infrared reflectivity efficiency losses have time to heat it (pure elemental gold metal reflects infrared best at around 95% and is why applied to backside of expensive quartz filament bulbs :)
The BEST filaments for radiant heating of water/humans are the pricier carbon filaments. They have near instant-on heat and generally peak closest to our target 3000nm wavelength we humans like to feel when we stand out in the sunlight warmth. I've not checked whether or not these dishes use carbon vs tungsten, but looks like decent tungsten upon casual inspection.
FYI: Old "radiant" steam heaters are a misnomer since they primarily heat the air by creating a natural heat-rise current in the air (aka: convection heating). Incidentally, this is the same reason why the gap size between double-glass insulating windows is so important since otherwise those windows become mini-convection heat-loss/heat-transfer panels in your wall :)
Try this at home: hold a piece of UNCOATED/UNPAINTED metal in front of a true parabolic dish heater with tongs/whatever such your hand doesnt heat the metal, and at same time place your bare hand at the same safe distance beside it and observe which heats up. Result: metal has barely warmed at all whereas your hand gets toasty fast and if too close even starts to get too hot feeling. If the metal is flat think of it as a mirror---you can make some of the heater's heat "turn a 90-degree corner" like using a mirror but to heat.
Plastics & Radiant Heater CAUTION: Some plastics like common polyethylenes coincidentally absorb infrared radiation optimally at 3500nm (3.5 micron wavelengths) which is near that of water's 3000nm. This means many plastics will absorb and heat as fast as you will in front of heaters like these, which weakens/ages them by fracturing polymer chains.
Finally, for those curious about what differentiates this type of 'radiation' from 'nuclear radiation', remember that any lightbulb (LED, CFL, FL, Incandescent), radiant heater, all radio and TV signals, lasers, x-rays, and of course sunshine is ALL electromagnetic radiation (EM) delivered by way of photons and it is the EM wavelength (energy per photon rather than number of photons) that determines whether the radiation is 'scary'. Scary or bad EM usually means ionizing radiation like UV, x-ray, or worse) whereas non-ionizing EM includes all visible light, infrared, TV/radio, microwaves, etc. Note, however, that right at the border of deep violet visible light and UVB/UVC ultraviolet is non-ioninizing UVA/violets now thought the principle cause of the deadliest melanoma skin cancers fueled by indirect DNA damage of free radicals generated by UVA/violets EM energy and catalysts (such as, ironically, non-metals-based suntan lotion as well as other naturally-occurring compounds in our tissues). Once you get into regular visible light and longer wavelengths (radio, microwaves, etc.) most people believe to be safe as the energy per photon falls to such low levels. Nuclear radiation, on the other hand, is entirely different yet and deals with non-EM particle radiation (e.g., stray neutron bombardment) which is extra 'scary' of course and not found in our heaters or lights LOL (unless you bought a second-hand looted chernobyl-irradiated heater I suppose).
Hope that helps. :-)
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This is a radiant heater, designed to throw a "beam of heat". As a science teacher explained in junior high some 40 years ago, they do not heat the air or a room, but the objects in the path. If you are looking to warm a room, especially quickly, you want a forced air ceramic/quartz heater. If you want to warm yourself in an otherwise cold room, this is your baby. Sadly, almost every time I go to CostCo, I see someone returning one of these. Reading reviews of similar products on the web, it is clear that many folks have no clue about radiant heaters.Like one of the other reviewers, I bought this at CostCo but for some friends who smoked on their patio and froze during the winter. They've both passed on now and their relatives gave it back to me. (I also have one in my shop.)
Our furnace is out at the moment and it is doubtful we can afford to fix it before winter is over. Here in Las Vegas it is currently 41 outside with an expected low tonight of 29. Last night it was 21.
I'm sitting here writing this with this heater about six feet from me and on medium. I'm comfortable (and shirtless) even though it is only in the low 60s in the house. (We have a couple of oil filled heaters.) My right side (heater side) is hot to the touch, my left side is cool. Over all though, I'm comfortable.
Where this unit excels is in my shop which is basically a walled in carport, but walled in by louvers. I.E. it's 41 in my shop. But I just aim this at my workbench from about six feet away and stay toasty while there at the bench.
My wife is a lizard. Very cold blooded and is always cold if the room temp is below 80. All I have to do is aim this at her on the couch and she's warm and toasty without driving me out of the room.
If you use these types of heaters as intended, they are more than enough to cook you.
The one thing I really like about these is that at full power, they only consume 1,000 watts. Our oil filled and ceramic/quartz heaters start at 900 watts on low and go up to 1,500 watts. That will run up the electric bill (about $100 a month per heater) and two of them on the same circuit will blow our circuit breakers. So using these radiant dish heaters as spot heaters do a better job for less money.
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I owned this for about 3 years before it died. Purchased from Costco (there are more reviews on there).It gives off a tremendous amount of heat in a limited space of 3 feet but that's it.The footlight is pointless and stop working after a year. One of the Costco reviewers had this to say: "Owned a few of these and the experience is the same and matching quite a few others here.This is an effective, LIMITED LIFE, product. It does what it says sends a very nice stream of heat in a very limited direction. BUT it has a limited life span of 1-3 years, depending on use and luck.
The problem always seems to come down to a faulty "tip" sensor, so that the "alarm feature" meant to warn you that the device has fallen off its perch goes off continuously, rendering the device useless. Clearly Presto has skimped on parts there and has little interest in correcting this as evidenced by user reports of this problem going back years... .
Note to Presto spend a few more pennies on parts and design improvement, and a few less on the marketing required to re-package the exact same thing every year and you have a winner here. As is however, strcitly, buyer beware."
I couldn't agree more.
Honest reviews on Presto HeatDish Parabolic Electric Space Heater Plus Footlight
We purchased this two years ago for use primarily in the office, which happens to be one of our cooler rooms. It works very well for this. It is plugged in on the opposite wall and directed towards the desk which is approximately 8/10 feet away. You must remember it heats objects in the room not necessarily the room. If you are sitting/working at the same place it will keep you very comfortable. It makes a small hum when it comes on but not annoying. We have two other older coil type space heaters and an infra ray one. They all use more electricity than this one--1000w vs 1500w or 2000w. However, they do heat an area and not an object. So it depends on what your needs are: moving around more, space heaters might be better. In the same area most of the time, then the Parabolic would be my choice. It has three heat levels and off which gives a very good temperature range. It has a night light that I feel is not needed but it is only a 1.5 v bulb. I guess the only thing I sometimes think would be nice is if it was oscillating. This is the second winter and so far so good.Find helpful customer reviews and review ratings for Presto HeatDish Parabolic Electric Space Heater Plus Footlight
Like many of the other users on here, I purchased this from Costco. I bought it about 2 years ago and just recently caught the first sign of its imminent demise, the footlight has stopped working and the buzzer started malfunctioning. Based on other comments I've read, it appears this is fairly common, so you should know that this product seems to have a ~2 year lifespan. Not bad, not great.So ignoring it's lifespan issues, I have exactly two complaints:
1) Very limited ability to direct the heat the heat dish has a fixed angle and elevation, so if you want to prop this up and have it warm you while you're sleeping, you can't. So it pretty much only works if you're directly in the beams path.
2) No incremental heat the dial on top of the heat dish appears to have gradual levels of heat. This is an illusion. The dish actually has 4 modes: off, low, medium, and hot. Low is unusable because you have to be hugging the dish to get any heat. Medium is the only usable one, although you have to move the dish around every few minutes to avoid burning any one part of your body. Finally Hot is only useful if you're interested in setting your house on fire. Realistically, it's only useful at great distances and very short periods of time, otherwise you will actually burn your legs and face.
Some positive aspects include the really good range, and its ability to get hot fairly quickly. Overall, I felt the heat dish was very useful and worth the money, but my two complaints prevent it from being a great product.
As a side note, this heat dish (even in Medium mode) will probably literally set fire to leather, so keep that in mind if you planned to use the heat dish near a leather office chair.
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