Low cost effective heating for bedrooms

Forums › Home Workshop DIY › Low cost effective heating for bedrooms

Mumx5

5 posts

Wannabe Geek

#168484 15-Mar-2015 21:11

I have a 3 bedroom brick home which is in a L shape to best describe it, that I rent. There is a heatpump down one end which overheats the lounge and even with doors open the heat never makes it to the bedrooms, all located at the other end of the house. The bedrooms all suffer badly from condensation during winter and are freezing cold to the point your breath steams. The house has relatively new insulation in the roof covering the entire home, as well as black plastic lining the ground and silver paper attached to the house.

The bedroom end of the house basically there is a hallway where the toilet and bathroom comes off with 2 bedrooms to the left and one to the right.

Previously I have used electric blankets and lots of bedding for the children, but now I am expecting a baby in the middle of winter (july) I need to really address keeping that end of the house warmer.

I was going to go get 2 x 2 packs of the ecosaver wall panel heater (425w) from the warehouse as they currently are being sold $129 for a twin pack and put one in each of the 3 bedrooms and one in the hallway however my house was recently redecorated and the painters advised they had come across these that were scorching the walls and people did not want them reinstalled. The other thing suggested was a Mitsubishi Oasis Dehumidifier which could be located in the hallway to pull the condensation off from that end of the house, but if I am going to pay out for that plus the hourly cost, and then on top of that I still need to heat that end of the house to an acceptable level for a young baby.

If I put a heater in the hallway the heat will face the bathroom and toilet (obviously those doors will be closed). Potentially wasted heat which would not distribute evenly to the bedrooms.

Obviously with a baby on the way, our income will be reduced so an "affordable" option is needed.

A heat transfer system was suggested but the landlord is not at all interested in this further outlay having in the last month redecorated the entire house, with new carpets and a new bathroom.

What would you recommend?

1 | 2 | 3 | 4 | 5 | 6

Mad Scientist
29689 posts

Uber Geek

Trusted

Lifetime subscriber

#1259867 15-Mar-2015 21:27

this is very unfortunate for 90% of new zealanders living in non insulated houses [those who argue for batts etc, don't, coz i've lived in the exact same house as the OP and after all the insulation at night you might as well sleep outside, same temp minus wind]

there is no cost effective heating as all heaters heating the same cubic volume needs the same amount of heat output.

the only cost effective one [over time] is a heat pump but you are renting.

surely an engineer could invent a heating blanket? that would keep babies warm without needing to heat the whole neighbourhood

Lenovo

Shop now for Lenovo laptops and other devices (affiliate link).

Aredwood

3885 posts

Uber Geek

#1259883 15-Mar-2015 21:48

First of all a heat transfer system would be a waste of time for a heatpump. You need a logburner to get high enough temps in the lounge to make the transfer worthwhile.

Recommend that you get the dehumidifier first. As all of the waste energy from the dehumidifier is heat. The power usage of the dehumidifier is also similar to 1 of those panel heaters. So you will effectively be using the same electricity twice. And even better - every litre of water that the dehumidifier collects is about 600W of free heat. So depending on how you look at it a dehumidifier is more than 100% efficient as a heater. (Google "latent heat of water" if you want to know why)

Also don't spend lots of money on any resistance electric heater. As expensive ones have the exact same efficiency as a cheap one. The only reason the ecosaver heaters are cheaper to run is because the put out less heat. (Same as comparing a 100W incandescent light bulb with a 25W incandescent light bulb)

Consider getting something like a heatermate http://www.geekzone.co.nz/forums.asp?forumid=141&topicid=143802 And then buy a big secondhand oil column heater off trademe for $5 or so. Only switch on the smallest element on the heater. This will help keep surface temps down. Which will be important when baby gets to the crawling / walking stage. And will help stop the room temp from overshooting the set point.

Set the thermostat to about 18deg. Although this doesn't seem very warm it will still take the chill off the air. And combined with the dehumidifier will make a big difference to comfort levels. Without needing to do alot of heating. If you try to make the room hotter. Heat loss increases exponentially with higher room temp Vs outside temp. So if you want all the rooms at a constant 24deg. Then be prepared to spend some serious money on power. Or pay to get a heatpump installed.

Batman

Mad Scientist
29689 posts

Uber Geek

Trusted

Lifetime subscriber

#1259896 15-Mar-2015 21:57

these how much are one of these [one that meets proper standards and won't fry your kid / house]

timmmay

20424 posts

Uber Geek

Trusted

Lifetime subscriber

#1259905 15-Mar-2015 22:03

The advice above is good. If you have a lot of moisture you need to find the source and ventilate, moist air is expensive to heat. A ventilation system helps a lot but you're renting. Dehumidifier fixes problems without considering cause but may be your best option.

Stan

929 posts

Ultimate Geek
Inactive user

#1259913 15-Mar-2015 22:12

Aredwood: First of all a heat transfer system would be a waste of time for a heatpump. You need a logburner to get high enough temps in the lounge to make the transfer worthwhile.

Recommend that you get the dehumidifier first. As all of the waste energy from the dehumidifier is heat. The power usage of the dehumidifier is also similar to 1 of those panel heaters. So you will effectively be using the same electricity twice. And even better - every litre of water that the dehumidifier collects is about 600W of free heat. So depending on how you look at it a dehumidifier is more than 100% efficient as a heater. (Google "latent heat of water" if you want to know why)

Also don't spend lots of money on any resistance electric heater. As expensive ones have the exact same efficiency as a cheap one. The only reason the ecosaver heaters are cheaper to run is because the put out less heat. (Same as comparing a 100W incandescent light bulb with a 25W incandescent light bulb)

Consider getting something like a heatermate http://www.geekzone.co.nz/forums.asp?forumid=141&topicid=143802 And then buy a big secondhand oil column heater off trademe for $5 or so. Only switch on the smallest element on the heater. This will help keep surface temps down. Which will be important when baby gets to the crawling / walking stage. And will help stop the room temp from overshooting the set point.

Set the thermostat to about 18deg. Although this doesn't seem very warm it will still take the chill off the air. And combined with the dehumidifier will make a big difference to comfort levels. Without needing to do alot of heating. If you try to make the room hotter. Heat loss increases exponentially with higher room temp Vs outside temp. So if you want all the rooms at a constant 24deg. Then be prepared to spend some serious money on power. Or pay to get a heatpump installed.

100% This

Any decent dehumidifier with some form of humidity control would do if the Mitsubishi oasis is too expensive (delonghi dimplex etc)

bfginger

1244 posts

Uber Geek

#1259924 15-Mar-2015 22:34

The bedrooms all suffer badly from condensation during winter and are freezing cold to the point your breath steams. The house has relatively new insulation in the roof covering the entire home, as well as black plastic lining the ground and silver paper attached to the house.

Do you mean the windows suffer from condensation? If they aren't double glazed that is to be expected. Dehumidifying the air should help with that. The silver foil insulation doesn't work unless it is installed correctly and even if there is insulation in the ceiling and under the floor that still leaves uninsulated walls and single glazed windows to let out lots of heat.

There is no difference between a wall panel electric heater and an electric oil heater other than maximum wattage output. The oil heater can be run at the same wattage when put on "low".

A Mitsubishi Oasis dehumidifier would help reduce humidity. Reducing humidity makes cooler air feel warmer and the dehumidifier puts out its own heat so it's like running a more efficient heater. Dehumidifiers don't dehumidify as effectively when the temperatures are lower but that model is supposed to be better at it. Don't buy the 16 litre model as it's only slightly cheaper but much less efficient than the 21 litre. Most models of dehumidifier don't work very well at lower room temperatures.
Boiling pots and showers are big producers of humidity so the house should have an externally vented rangehood and extractor for each. It's in the landlord's interests to install them as the dampness released into the house damages it.

Ventilation systems only help if they're good qualtiy controlled ones with humidistats and thermostats. The typical ones installed in NZ homes are bad enough they should be illegal.

Where in the country are you?

richms

27967 posts

Uber Geek

Trusted

Lifetime subscriber

#1259927 15-Mar-2015 22:44

Get the dehumidifier and see how things are after its been running for a day or so. They are usually only 400 watts or so, impact on the powerbill will be stuff all and will do the most to help if you find the place to be damp and cold.

Once its dryer in side, you can start to look at other heating. The panel eco heaters are just gutless heaters. You can get a tiny oil heater that is 500 or 600 watts for cheap as, and that will be more effective than the 450ish watt eco heater and they dont need installing and take up wall space.

I prefer my bigger oil heater tho, as it has a larger area so it seems to convect better even when on low than the small ones do. I keep the small one for keeping legs warm when it gets really cold in my garage workspace which has an uninsulated garage door at one end of it.

Richard rich.ms

nakedmolerat

4625 posts

Uber Geek

Trusted

Lifetime subscriber

#1259932 15-Mar-2015 23:07

Mumx5:

I was going to go get 2 x 2 packs of the ecosaver wall panel heater (425w) from the warehouse as they currently are being sold $129 for a twin pack and put one in each of the 3 bedrooms and one in the hallway however my house was recently redecorated and the painters advised they had come across these that were scorching the walls and people did not want them reinstalled. The other thing suggested was a Mitsubishi Oasis Dehumidifier which could be located in the hallway to pull the condensation off from that end of the house, but if I am going to pay out for that plus the hourly cost, and then on top of that I still need to heat that end of the house to an acceptable level for a young baby.

I have done some research in the past. This ecosaver wall panel heater, is basically useless at 425w. You will need to put 2-3 of them on average room size to actually increase the room to a comfortable temperature.

If I put a heater in the hallway the heat will face the bathroom and toilet (obviously those doors will be closed). Potentially wasted heat which would not distribute evenly to the bedrooms.

I agree, heater on the hallway is not a good idea.

Obviously with a baby on the way, our income will be reduced so an "affordable" option is needed.

I have a portable dehumidifier for small room. I used it when I live in a crappy old flat as a student few years ago in Dunedin. It has been in the storage and boxed. Happy to pass this to you if you are keen.

What would you recommend?

I would not bother with dehumidifier at all. I have lived in Dunedin, in a crappy brick flat. Landlord installed over $3k dehumidifer system and it is useless. I am biased because of this past experience (I don't think it works quite well).

My choice to heat a room is to get a huge 2kw heater with temperature control/thermostat.

After the baby is awake, air the room by opening the windows then put the baby in the heatpump environment.

You really need a good powerful heater. 2kw is minimum. Two heaters I bought from The Warehouse in the past are excellent but unfortunately they don't appear in the catalog anymore. I don't like oil column heater as the kids can inadvertently touch it - so I have the ceramic type instead - cool to touch. They cost close to $200.

mattwnz

20038 posts

Uber Geek

#1259935 15-Mar-2015 23:10

Why don't you ask the landlord to install another heat plump down the other side of the house and tell them there isn't enough heat down that end? Unless you ask them , they are unlikely to do anything to help.

Niel

3267 posts

Uber Geek

Trusted

#1259940 15-Mar-2015 23:32

I've built my own heat transfer system (actually an air circulation system), but with the fan turned around so stale air is sucked out of bedrooms and returned to the living space where it mixes with the aircon air and heated air goes through the hallway back to the bedrooms. The traditional way of blowing air into bedrooms works only if you have a concentrated heat source (fireplace chimney) as the air cools when it goes through the ducting. With my system at least the cooler air is blown into the living space where it mixes with aircon'ed air. Also there is absolutely no fan/air noise in the bedrooms, the noise is where you blow air out (i.e. in my living space).

Before we had the aircon, in both our new built house and or previous 40 year old house, the best heating I've had was with cheap 5-fin electric heaters and placing a fan on top of them blowing down (was a cheap computer fan on a 12V power supply). Normally the thermostats in oil fin heaters don't work because the metal heats up and then the thermostat does not sense room temperature. With the fan however, the warm air is blown down and the area where the thermostat is does not heat up. Also the warm air is blown to the floor where it spreads through the room before it rises, instead of rising straight above the heater and collecting against the ceiling. The setup sounds stupid, but my wife was impressed in the living room she could feel the warmth at her feet with the heater 5m away. And do also get a dehumidifier with humidity sensor.

Cut all drafts that you can. Recessed down light fittings are bad as they are not sealed, but you will be surprised how much draft you get through the range hood and bathroom extractor fan ducting - and I don't mean while they are in use. You do get draft stoppers for ducting, but you might want to look at eBay as local prices are high. There is one model that is a sock inside a pipe that collapses when the fan is off, to stop the draft. All others are metal plates with a spring where you loose a lot of air flow when the fan has to fight the spring to open the flap. The sock system works well.

You can never have enough Volvos!

Niel

3267 posts

Uber Geek

Trusted

#1259941 15-Mar-2015 23:35

Regarding touching a hot heater, I was surprised with a fan on top of my electric oil filled fin heaters they were mostly cool to the touch. The fans would blow away the heat before the heater can heat up to where it could burn your skin.

You can never have enough Volvos!

Niel

3267 posts

Uber Geek

Trusted

#1259943 15-Mar-2015 23:37

You can never have enough Volvos!

kiwirock

681 posts

Ultimate Geek

#1259944 15-Mar-2015 23:39

Keep in mind, even dehumidifiers let off some heat from running the compressor etc... So it's not all wasted electricity.

You need to regularly service a dehumidifier though. The coils will eventually get dusty and start growing mold or fungi from the lovely damp environment on the heat exchangers or drip tray. You don't want this blowing mold spores in to a nursery if it's tucked away over summer and pulled back out in winter.

I'd use a 400W panel heater if it's a rental place. You probably should ask if you go drilling holes in the walls. So perhaps a stand up heater that also offers 500W and a thermostat.

For the first few months we had bub in our room with an oil heater on thermostat so we all stayed warm. But we slept in the end bedroom and bub in the middle room after a few months. Doesn't take long for them to regulate their own body heat better.

Welcome to parenthood. Kids cost full stop :o)

kiwirock

681 posts

Ultimate Geek

#1259945 15-Mar-2015 23:52

Niel: Regarding touching a hot heater, I was surprised with a fan on top of my electric oil filled fin heaters they were mostly cool to the touch. The fans would blow away the heat before the heater can heat up to where it could burn your skin.

Safer to put a fan behind it than on top. If the fan or fan power supply failed in the middle of the night... hmmm.

Aredwood

3885 posts

Uber Geek

#1259946 16-Mar-2015 00:03

nakedmolerat:

I would not bother with dehumidifier at all. I have lived in Dunedin, in a crappy brick flat. Landlord installed over $3k dehumidifer system and it is useless. I am biased because of this past experience (I don't think it works quite well).

My choice to heat a room is to get a huge 2kw heater with temperature control/thermostat.

After the baby is awake, air the room by opening the windows then put the baby in the heatpump environment.

You really need a good powerful heater. 2kw is minimum. Two heaters I bought from The Warehouse in the past are excellent but unfortunately they don't appear in the catalog anymore. I don't like oil column heater as the kids can inadvertently touch it - so I have the ceramic type instead - cool to touch. They cost close to $200.

The landlord probably installed an HRV, or a DVS, or one of the many clone systems. All they do is take air from the roof space and blow it into the rooms. Which will only fix a condensation problem that is caused by too much moisture generated inside the house and where there wasn't enough ventilation.

But when outside moisture levels are also high. Then such systems are useless. And in a brick house, Often the space between the framing and the bricks is open to both the roof space and the underfloor space. So an HRV style system ends up blowing damp underfloor air into the house. And if the house has a clay or concrete tile roof. often the tiles will also release alot of moisture into the roofspace air. And the HRV sales reps AFAIK get paid commissions for each system sold. So it is unlikely they will admit that their system won't be suitable for a particular house.

So although such systems can dehumidify in the right situations. They are definitely not true dehumidifiers.

1 | 2 | 3 | 4 | 5 | 6