Air Con or Kerosene heater?

[stemik 14]

I wonder if anyone can help, I have to think about heating the house soon.

 

Which would be cheaper to run

 

1. Air conditioner (with heater) We have both 100v and 200v air cons.

or

2. Kerosene (toyu) fan heater. We have an oilstorage tank and pump.

 

Thanks

[RobBright 35]

Depends on size of room, how long you run it for, output of the kerosene heater, cost of the kerosene.

[snowdude 44]

If you have a biggish toom 8 tatami or more then the kerosene heater will be cheaper. But if you choose a kerosene heater make sure it is capable of heating a room a bit bigger than the room/s you intend to have it for, then you will only need to run it on a low eco setting which uses very little fuel.

If for example you buy a heater that is for a 6 tatami mat room and your room is 6 or more on very cold days it will need to be run flat out.

If you buy a heater for example that is for an 8-10 mat room and use it in a max of 8 then you will only need to use it on a low setting to heat the room just as well.

Something to think about before you buy if you choose the fuel heater.

[stemik 14]

the room is a "great room" . I would say about 25 to 30sq meters. With the ceiling going up to the second floor.

 

I was thinking...that the kerosene heater needs to use

1. kero

2. electric for the pump

3. electric for the fan

[RobBright 35]

Na, not all kerosene heaters are plugged in to the mains.

 

The in-laws have a 12 tatami one, like snowdude suggested, for an 8 tatami room, and runs off gas only. It has a 360 open face, so heat radiates out without the need for a fan.

[stemik 14]

yes, i have seen them.

 

But mine will have to go against the wall, as that is where the oil inlet and exhaust is located.

[Thundercat 60]

In light of the fact that you can have a proper exhaust hook up I would suggest going for the kerosene heater. Another consideration is that the heat raises and if you are using the aircondition to heat the room it's already elevated meaning the floor area may remain cool.

[NoFakie 45]

Is that your living room Stem?

[panhead_pete 27]

Have you considered straight electrical heaters Stemik? There are some very efficient ones now that actually look OK too. Wish I could find the link to the ones I was looking at 3 months ago.

[Jynxx 4]

What about ventilation?

I only know those old fashioned kero stoves, you have to open the window once in a while to get some fresh air ...

[Tubby Beaver 209]

yeah thats the one I have Jynxx..........great heat off of it but it does become smelly!!

No fan and not plugged into the mains, just burns kero and has a glass pipe/silver back combo to blast the heat out

[snowdude 44]

I have three kero heaters of various sizes for different rooms, they are all fan assisted new types.

They do smell a little when you first switch them on, which actually I like, when I smell the kerosene I know winter is here or at least getting close!

We do open the windows slightly or open the door now and again to let air circulate, but in general we use them with in a closed room. The latest ones are very effecient now!

[Jynxx 4]

If you do let the heat out by ventilating, that does effect the energy rating in a big way, don't you think?

But then again, in any situation, it's nice to open the window up cos it does get stuffy. All the CO2 we breath out!

[RobBright 35]

Originally Posted By: panhead_pete

Have you considered straight electrical heaters Stemik? There are some very efficient ones now that actually look OK too. Wish I could find the link to the ones I was looking at 3 months ago.

Kerosen is pretty cheap, well it is where we are compared to electricity.

[stemik 14]

Originally Posted By: Mr Wiggles

Is that your living room Stem?

Yes.
We already have two 220v air cons in the room.
We had a kerosene heater last year but it was old and finally gave up.
A new large kerosene heater is about 150,000yen.

We also have a wood stove but we are only going to use it on the weekends.

[stemik 14]

Originally Posted By: Jynxx

What about ventilation?
I only know those old fashioned kero stoves, you have to open the window once in a while to get some fresh air ...

we have an exhaust pipe

[Jynxx 4]

If you have a slow combustion wood stove, why not use that every day.

All you need is a ceramic electrical heater to get a little warm blast just when you got into the room, until yuu get the wood stove going.

Another good alternative is to get a small heated carpet.

Since hot air rises, I'm not partial to air con heating where the air outlet is pretty high up.

[stemik 14]

Originally Posted By: Jynxx

If you have a slow combustion wood stove, why not use that every day.
All you need is a ceramic electrical heater to get a little warm blast just when you got into the room, until yuu get the wood stove going.
Another good alternative is to get a small heated carpet.
Since hot air rises, I'm not partial to air con heating where the air outlet is pretty high up.

good question Jynxx, actually in winter we are out of the house by 7am and not back until 8pm - and the kids (and me) are so tired they just go straight to bed.
On the weekends they are back around 3pm so we spend more time in the room.
One full load usually burns for about 10 hours. We plan to have it on 24 hours over the weekend

[iiyamadude 6]

Originally Posted By: stemik

the room is a "great room" . I would say about 25 to 30sq meters. With the ceiling going up to the second floor.

That sounds great!!!

(bum-tish)

[muikabochi 208]

Kerosene (toyu) fan heater. We have an oilstorage tank and pump.

 

Sounds like you might miss out of the most fun part! Finding out you have run out and need to shovel out the car to get to the petrol station. Cursing all the time.

[RobBright 35]

That sounds awesome

[NoFakie 45]

Originally Posted By: RobBright

Originally Posted By: panhead_pete

Have you considered straight electrical heaters Stemik? There are some very efficient ones now that actually look OK too. Wish I could find the link to the ones I was looking at 3 months ago.

Kerosen is pretty cheap, well it is where we are compared to electricity.

True but there are two types of electrical heating.

1. resistance heating where a large current is used to make an heating element hot.

2. heat pump where heat is moved from one place (here outside) into your home. A fridge is a heat pump dumping heat from inside the fridge into the room. Air cons are heat pumps too, taking heat from inside in cooler mode or from outside in heater mode.

Kero is definitely cheaper than 1. The classic examples of 1. in Japan are kotatsus and hot carpets. They are expensive to run but heat a very localised area. Trying to heat a whole room with resistance heating, such as those electric radiators you see, is super expensive in a typical draughty Japanese house.

A modern air con will move about 4kWh of heat into your room at the cost of 1kWh of electricity. Even when the outside is cold, say 0C, there is still heat energy to move inside since 0C is 273C on the Kelvin scale. However, the air con won't be as efficient as when its 10C outside. The efficiency may fall to 3:1 or below. If the thing is working efficient enough, an air con is slightly cheaper to run than a kero heater. No fumes either.

[RobBright 35]

Originally Posted By: Mr Wiggles

Air cons are heat pumps too, taking heat from inside in cooler mode or from outside in heater mode.

Why would the air con bring in heat from outside, if it is cold outside?

Thought they (and fridges) used compression methods to heat up/cool down?

[NoFakie 45]

The answer to question one is that "cold" air for you is still hot in terms of physics. "Low temperature" for physics is minus 150C or below (!) Heat energy can still be extracted from cold air, though the warmer it is, the easier the extraction is.

 

Compression is part of the pumping process. Ultimately the coolant with "heat" from inside the fridge goes through the coils on the back and the heat is dumped into the room.

[RobBright 35]

Because of molecules zipping around in a gas....