BS: Best safest space heater

Subject: BS: Best safest space heater
From: GUEST,mg
Date: 21 Sep 11 - 01:27 AM

I might want to buy one for Sunnycamp to heat at least part of a rec building, drafty and damp...any suggestions? What about the Bob Villa one he advertises...they ahve been on sale recently. It has to be truly safe and electric. No propane. I have those oil filled things and they are very close to worthless here. mg

Subject: RE: BS: Best safest space heater
From: Joe Offer
Date: 21 Sep 11 - 01:59 AM

Well, the EdenPure Heaters that are recommended by Bob Vila do look pretty good, but they ain't cheap. I've been looking for a heater to keep 96-yr-old Grandma warm this winter, and I may consider one of these.
Many space heaters are pretty flimsy, and I wouldn't trust 'em.

-Joe-

Subject: RE: BS: Best safest space heater
From: GUEST,Ebbie
Date: 21 Sep 11 - 02:19 AM

Last winter when it was so cold here in the apartment building and the owner didn't want to spring for more heaters I bought two Honeywell heaters (@ $64.) and handed them out. They are adaptable and flexible for different modes, fully enclosed, put out a lot of heat, like most, stop if tipped over, oscillation feature, heavy, stable construction. In short, I'll buy a couple more this winter if I need to.

Subject: RE: BS: Best safest space heater
From: Penny S.
Date: 21 Sep 11 - 04:13 AM

Dyson has just brought out a model using his no fan technique - probably horribly expensive, but safe and electric.

Dyson Hot

Penny

Subject: RE: BS: Best safest space heater
From: Richard Bridge
Date: 21 Sep 11 - 05:20 AM

Do check running costs. Here in the UK electricity is always the most expensive way to heat anything. Agricultural hot air blowers that burn paraffin and use an electric fan can heat a large space very quickly (but are noisy; and smell a bit of paraffin, which I quite like but many don't) and then smaller oil-filled radiators and the warmth of folky bodies can maintain temperature, maybe.

Subject: RE: BS: Best safest space heater
From: Jim Dixon
Date: 21 Sep 11 - 07:56 AM

British paraffin = American kerosene

By the way, the idea that some electric heaters are more "efficient" than others is bunk. All electric heaters are 100% efficient since they turn 100% of the electrical energy they use into heat.

You might be better off buying several small cheap heaters than one big one.

If the building is truly drafty, it might be a better investment to caulk the cracks.

Subject: RE: BS: Best safest space heater
From: Richard Bridge
Date: 21 Sep 11 - 08:50 AM

US - "drafty" - UK "draughty".

Subject: RE: BS: Best safest space heater
From: Bill D
Date: 21 Sep 11 - 10:27 AM

Ah, yes..."ugh"

The wind was rough,
And cold & blough.
She kept her hands
Inside her mough. ☺

(we prefer the enclosed oil heaters, except for one tiny little radiant heater for a small bathroom)

Subject: RE: BS: Best safest space heater
From: open mike
Date: 21 Sep 11 - 11:36 AM

The (supposedly Amish made) heaters such as http://www.heatsurge.com/
most of these devices cost around $300, the Heat Surge page has some
"scratch and dent" models for $267 but that is still a bit pricey for a weekend! I hope you find something that works for you! I hope the camp goes well. I have fond memories of the time I attended your camp!

Subject: RE: BS: Best safest space heater
From: open mike
Date: 21 Sep 11 - 11:49 AM

the heat surge stove called "Accent" which is going for $219 in the scratch and dent sale..

Subject: RE: BS: Best safest space heater
From: GUEST,mg
Date: 21 Sep 11 - 12:54 PM

Thanks...I'll keep checking...I actually like those big round ones that blast out heat. I am concerned about blowing circuits etc. at this old camp. If anyone is very good at keeping things going, please come for free to Sunnycamp and help us figure out the dishwashers and circuit boxes and various other things...there is a new caretaker and I am not sure how much she knows...we have had people in the past who are good at these things but they are probably not coming this year (probably because they know we are overly dependent on them). mg

Subject: RE: BS: Best safest space heater
From: JohnInKansas
Date: 21 Sep 11 - 03:38 PM

In the US, common household circuits are typically protected by 15 Amp circuit breakers, and at the 110 Volt nominal supply voltage the maximum power that can be used on a single circuit is approximately 1500 Watts (1.5 KW). A single circuit intended for "light appliances" may have a half dozen outlets for lamps and other low demand devices; but the entire circuit is limited to the 1.5 KW circuit breaker value. Most homes include a few circuits with 20 Amp circuits and in newer ones all circuits may be 20A ones, but in older homes they usually are installed only for specific uses such as "window air conditioners" or other higher demand appliances. Garage/workshops, even in older constructions, fairly frequently may have 20A circuits for the "power tools." The power limit for a 110V 20A circuit is still only ~2.2 KW, with few appliances showing higher than a 2 KW cutoff. Due to the common appearance of 15A circuits, the selection of available small appliances that exceed 1500 W is extremely limited here.

The "center neutral" configuration for US power permits relatively easy addition of a 220 Volt circuit, usually with 20A, 30A, or 50A breakers but in most cases each outlet will be a new installation specific to something like a stove, whole house air conditioner, electric clothes dryer, or the arc welder in the workshop. In principle, a 50A 220V supply circuit could provide ~11 KW of heating. Anything larger would require building permits and architectural and engineering consultants in most cases.

I've had insufficient exposure to UK and other practices to comment, but similar limits are likely to prevail. Perhaps someone can fill in the gaps(?).

At the 1.5 KW level, very small heaters are available here that will produce all the heat possible for <$40 (US). A typical, and very popular, one might be the Holmes "Cube." Similar ones are available from other makers.

(A single Holmes Cube - or my similar Emerson one - can warm my "barely insulated" 10 ft x 24 ft garage by 10 degrees or a little more, given a little time to come up. A pair of them likely could provide quite comfortable "room temperatures" down to around 30F outside air temps. I've only got two usable circuits in the garage so I haven't considered a third.)

These small units can be easily placed almost anywhere that an outlet is available, include a fan, a crude thermostat, overheat and tip-over protection. Disadvantages are that the element is hot enough to ignite a flammable object placed very close to the air outlet and being small they can be tipped over fairly easily. In nearly all cases the overheat switch will cut off the heater before "flames break out" but it's not too uncommon to see nearby items "heat damaged" where I've seen careless people use one.

The "cube" style heaters would be classed as "forced-air incandescant heaters." Older ones generally used wire coil heating elements, but some newer ones claim "ceramic heaters" that may be a little more durable. Efficiency is the same.

Larger units that work on the same principles can have the heating elements more fully enclosed, can use larger fans, and hence the output air is at higher volume but at lower temperature. The potential for better warm air distribution is obviously present, but the total amount of heat that can be distributed is exactly the same.

In the same small appliance groups, "radiant heaters" rely on the warming of objects in the room by the "heat rays" (infrared light) radiated by the heater. The heated objects will (theoretically) warm the air that surrounds them and the air will (theoretically) be circulated by convection. Since the conversion to "radiation" isn't perfect, the remainder of the input power is dissipated as heat within the unit, so some of these have a small fan to "blow the residual out" but that contributes no additional foom heating. A "radiant heater" can char or ignite objects placed too close to the "radiant surface" although the larger area of the "radiating surface" possibly makes this a little less likely than with an incandescant heater. Small units should of course include tip-over and overheat cutoffs. Most such units include a "thermostat" (more accurately a power setting control) but the huge lag between changes, before the effect is apparent in air temperatures, may make adjustment to your liking somewhat tedious.

The third kind of small heating appliance common here is the "electric radiator," or more correctly the "convection heater." Most such units are configured to visually resemble a hot water (steam) radiator, with enclosed heating elements and a convection circulated internal fluid that warms a fairly large external surface. Room air is warmed by contact with the surface and circulated via convection. Due to the large "warm surface" the temperatures at all exposed surfaces can be kept quite low, so there is little danger of burning anything, although some may get hot enough to melt a synthetic sweater or similar item(s) carelessly draped on them. Tip-over and overheat protections still should be included. This kind would probably be the "safest" for use in a more-or-less permanent meeting room, with the disadvantage that the time-lag to bring a room to comfortable temperature can be rather long, requiring the heater to be turned on long before the session starts, and increasing the possibility that it will be left on for longer periods, thus increasing operating costs. An auxiliary air circulation device, such as a ceiling fan perhaps, may be wanted with one of this kind, or with the "radiant heater" type above.

The maximum heating you can obtain from any of the three kinds of small heaters is exactly the same, since the limit is due to the circuit capacity and doesn't depend on what you plug into the socket. These smaller units are intended to be "portable" but for a dedicated use a clever person should be able to fasten one down at least semi-permanently and create a "safe zone" to assure adequate clearance from hot surfaces and air flows. A "stable" location is essential and recommended.

For most of these units, generically called "room heaters" or "area heaters," any thermostat will not be marked by temperature, but will be a "relative to maximum output" setting. A thermometer on an opposite wall, indicting in degrees, is a good idea, for reference.

Even in "deluxe" configurations, no heater of any of these kinds should cost more than about $100 (US) unless you're looking for a much more peramanent solution or have other things** that must be considered.

**[Prof: "If black objects are better radiators, why are radiators painted silver."
Bright Student: "Because it's prettier.]

Although a permanent installation probably isn't what you want, if a more sophisticated, or higher capacity, heater is wanted the appropriate devices would be in the class of "auxiliary furnaces" that would imply a permanent mounting, installation of a separate dedicated electrical circuit, a remote (wall) mounted control thermostat, and most likely a forced-air circulating system (or at least a fan). Here, most people would likely opt for a forced-air gas furnace of one kind or another (which may also require adding a gas supply line and an exhaust stack), due to operating economy. (The fuel used for basic heating should be considered, usually.)

Permanently or semi-permanently mounted gas or other fuel fired "room heaters" with forced air blowers are available in an intermediate range, sometimes called "space heaters," but require very careful consideration of venting and other factors for safe operation, and here such units are almost exclusively found (and marginally legal) in open detached garages/workshops. (A "safe" (?) installation of such units requires installation of a "chimney" for combustion gas removal and isolated combustion air inlets. Using room air for combustion air is legal only for small capacities as for water heaters in separately enclosed and isolated spaces. Some people take the risk of lesser attention to details with these units, but I'm easily frightened by them.) Electric units in this class are available, but the higher current requires a dedicated outlet and operating costs are sufficiently higher that they're seldom seen here.

Although UK (and other) wiring uses different voltages and presumedly different circuit protection levels than here, I would expect that "portable heaters" will have a power limit somewhere near the 1500 W found here. You are unlikely to find a "heater" with any higher capacity that doesn't require a dedicated (and likely new) circuit you're unlikely to have available. You should be able to start at the $20 (US) level and step up to whatever contributes to safety for your circumstances, but all heaters you're likely to find will be interchangeably equivalent in heating capacity regardless of how many "ad-features" and "look-goods" you also pay for.

(But the trick is to find the exception to the generalizations that does something for you.)

John

Subject: RE: BS: Best safest space heater
From: open mike
Date: 21 Sep 11 - 04:22 PM

if you want an answer, just ask John!!

If you really want the room to warm up
play fiddle tunes and get everyone dancing..
then you will have to throw open the doors
and windows to cool down!

Subject: RE: BS: Best safest space heater
From: Richard Bridge
Date: 21 Sep 11 - 04:58 PM

UK.

This is in round figures.

UK runs 220 Volts. It used to be 240 but our masters which art in Brussels have been standardising things again. In fact actual supplies are often 240V.

A house will have power ring mains, and each such ring main will be fused (or have a cutoff switch) 30 amps at the fusebox (consumer box). So you can get nearly 7KW out of a ring main. But squarepin UK plugs are fused at no more than 13 amps. Call it 3KW. You can't get (well, you can't easily get) the standard size fuse in higher ratings. However, if you WANT to take a chance on melting the plug or the socket you could add a strand or two of wire to the fuse and rely mainly on the fusebox.   In theory you should not melt the ring main or start a fire under the floorboards. Probably. Also, there may be up to four (well, I've never seen more) of those rings on the consumer box.

There well also be lighting rings, probably tripped at 16A but it might be 10 or 6.

Spur mains are permitted under certain circumstances.

You MAY find cooker or shower spurs run in doubled 30Amp housing cable, fused or tripped at 70A at the board, but you shouldn't!


To add a ring or spur can only be lawfully done by a part P certified electrician, and it is illegal to sell a house without a part P certificate. Silly really 'cos any fule who can pass O level physics should be able to sort a basic AC circuit, but some landlord killed a tenant and Parliament intervened..

Do not play about with industrial premises without exact information. A house will only be on one phase of the grid, but industrial premises will often have more than one phase and so potentials can be well over 400 volts. Also the earths of the two phases are often off relative to each other - enough to give a guitarist whose guitar amp is on one phase a nasty but not lethal surprise using a microphone on a PA amp on a different one. They SHOULD both go back to local earth but faults are not that rare.


Agricultural premises are riskier. There will almost certainly be all three phases in there somewhere, and wiring dating from before the first world war, repaired by farmers with hairpins nails and binder string. Farmers never fix anything right.

Subject: RE: BS: Best safest space heater
From: JohnInKansas
Date: 21 Sep 11 - 08:23 PM

Farmers never fix anything right.

I'll give many of our farmers credit for being able to fix a lot of stuff "right enough to work," but it's D$@#%d sure they never leave notes for the next unsuspecting fixer. "Riskier" is probably an understatement.

I do have some documentation on obsolete US wiring methods, some going back to DC distributions, and some of that would make a smart squirrel reluctant to get in an attic. Fortunately(?) most houses wired with those methods burned down long ago, although I've seen remnants in a couple of abandoned sheds that collapsed for other reasons.

John

Subject: RE: BS: Best safest space heater
From: lefthanded guitar
Date: 22 Sep 11 - 07:36 PM

I'm coming in late here and can't really absorb some of the tech info BUT I will tell you for anyone in the US, Vornado makes nice sturdy heaters that get a small or medium sized room warm. I've used two and they are much better than any of the 'cubes'.

Subject: RE: BS: Best safest space heater
From: dick greenhaus
Date: 22 Sep 11 - 08:09 PM

Probably out of the price area being considered, but a small pellet stove, requiring an outside vent, works beautifully.

Subject: RE: BS: Best safest space heater
From: GUEST,Burton Coggles
Date: 23 Sep 11 - 03:06 AM

However, if you WANT to take a chance on melting the plug or the socket you could add a strand or two of wire to the fuse and rely mainly on the fusebox.   In theory you should not melt the ring main or start a fire under the floorboards.

That's about the most stupid piece of advice I've seen on Mudcat. Don't do it!

And its 230 v +/- 10%in the UK.

Pete.

Subject: RE: BS: Best safest space heater
From: Richard Bridge
Date: 23 Sep 11 - 04:09 AM

It was in fact a warning!

Subject: RE: BS: Best safest space heater
From: Richard Bridge
Date: 23 Sep 11 - 04:09 AM

And I've actually seen from 210 to 250

Subject: RE: BS: Best safest space heater
From: open mike
Date: 23 Sep 11 - 03:13 PM

is there a place where you can have an outside bonfire or barbeque pit?
or perhaps bring a barbeque grill or brazier or weber to have a wood or charcoal fire to huddle around...

Subject: RE: BS: Best safest space heater
From: mg
Date: 23 Sep 11 - 03:43 PM

There is an outdoor space for bonfire..trouble is weather could be pouring down rain by then...we'll have a good fire in main lodge..I just have to heat this sort of rec room in a drafty building..I think it doesn't even have real windows..just shutters...I think a couple of space heaters would do it, but I do not want to blow circuits etc...I know those oil filled ones are worthless here because I have one in my tiny cabin and it never gets warm or undamp...would do nothing in a larger room. I will probably get one of the ones suggested above at Costco and just have people scrunch together. I wish someone would come to camp who was an electrician. Free camp if you are...mg

Subject: RE: BS: Best safest space heater
From: GUEST
Date: 23 Sep 11 - 07:58 PM

A

DOG

Subject: RE: BS: Best safest space heater
From: Sawzaw
Date: 23 Sep 11 - 10:27 PM

It it is to be electric, I like the oil filled type that look like an old fashioned steam radiator. They are silent and create a column of heated air that rises to the ceiling, "mushrooms" and circulates down the walls. Then the air crawls along the floor back to the heater to be reheated and rise again. Plus you get radiated heat along with the convected heat.

It it is to be gas, the ones that are outside vented are safer than the unvented ones. Safer still are the ones that draw combustion air from outside and exhaust it externally too. The air inside is sealed off from the outside air. No unburned gas or exhaust fumes and get inside but you need to put a hole in the wall to vent it.

I know from my experiences with an unvented gas log that unvented heaters burn whatever is in the air over and over again. If there are any fumes in the air such as odors from painting, your nose and eyes will be irritated until you turn it off an open some windows.

There may be oil burners with sealed combustion but I don't know of any.