dehumidifier - what uses less energy running on high or low?

Cardew

Further to the above:

http://www.homebuilding.co.uk/advice/key-choices/heating/ventilation-options

Previous changes to the Building Regulations brought Parts L and F closer together. This is because ventilation is rapidly becoming the greatest source of heat loss in new dwellings as the standard of insulation continues to improve.

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CashStrapped

Unfortunatly you seem to be in a catch 22. The issue is that you cannot afford to heat your house, at the same time you are releasing a huge amount of water vapour into the air from breathing, cooking and especially drying clothes indoors. A large amount of the damp will be caused by you.

You are then trying to remove the water you put into the air by using a dehumidifer.

It is like walking around the house with a leaky bucket. Rather than catching the water in another bucket as it leaks (or fixing the leaks) you are trying to mop it up (with a dehumidifier).

Regarding using a dehumidifier as a heater heat: While it is efficient in terms of extracting heat from the air, it is not designed to heat a room. So while it may cost less to run than say an oil filled portable radiator, the heat emitted is not enough to increase the temperature much nor sustain it over a long period. Furthermore, the colder the room you are in, the less effective it becomes at producing heat. Dessicent dehumidifers produce far less heat, so they are not any good at heating either.

https://www.consumer.org.nz/articles/low-wattage-panel-heaters

Interesting article comparing all the options.

CashStrapped

Hi Cardew - appreciate your responses.

I agree that it is a balance. More often than not however, the balance is too far in the direction of "not enough controlled ventilation". I also have nothing agaisnt the use of a dehumidifer. As you say, the article points this out as an option, however this should be in conjunction with all the other things, which will mean total reliance on a dehumidifer is reduced greatly.

I think that homebuilding quote is refering to new properties that are still being badly built with a huge amount of uncontrolled ventillation. A large amount of our new housing stock is still built to 1960s standards in terms of insulation and airtightness, which is a travesty. I read an article last year about a new housing project, which was ment to be super insulated, airtight properties with a cheap mvhr system. It turned out they leaked more air than a sieve and rendered the mvhr system expensive and useless.

All houses now should be built to passivhaus standard. Then you have a mvhr system installed and that ventilates the house with very very minimal heat loss.

Cardew

CashStrapped wrote: »

Regarding using a dehumidifier as a heater heat: While it is efficient in terms of extracting heat(sic) *from the air, it is not designed to heat a room. So while it may cost less to run than say an oil filled portable radiator, the heat emitted is not enough to increase the temperature much nor sustain it over a long period. Furthermore, the colder the room you are in, the less effective it becomes at producing heat. Dessicent dehumidifers produce far less heat, so they are not any good at heating either.

https://www.consumer.org.nz/articles/low-wattage-panel-heaters

Interesting article comparing all the options.

Nobody is advocating using dehumidifiers as heaters. However your posts do not seem to appreciate 'whot that bloke Einstein stated'. Namely that energy cannot be destroyed. The relevance of that to this subject is that, say 1kWh consumed by the dehumidifier will produce the same amount of heat as 1kWh consumed by any other heater.(actually fractionally more)

Obviously if your property is ventilated sufficiently to remove all the moisture produced, then a dehumidifier is not required. That said, steps should be taken to reduce the moisture being produced.

However many homes cannot get rid of the moisture and the use of a dehumidifier is the best compromise solution.

Indeed the link you posted advocates the use of dehumidifiers where there is a dampness problem:

Dehumidifiers and heating
It may seem strange to use a dehumidifier to heat a room. But dehumidifiers deliver more heat to the room than they use in electricity – so they warm and dry the air. For a fuller explanation see our dehumidifiers test.

* moisture

vickyanne_2

I don't know all the tech stuff some of you know but I do know that we saved a lot last winter by using a desiccant dehumidifier upstairs.
We've got storage heaters downstairs and normally use oil filled radiators if we need heat upstairs - we're reluctant to add another storage heater up there as we like it cool.

We bought the dehumidifier with the lowest energy consumption we could find (laundry setting) and used it in the spare bedroom to dry virtually all the washing and after showers and it kept the upstairs feeling warm and dry. Our house is a small 3 bed and very well insulated. I know it was a warm winter but our electricity bill was over £200 less, a lot of it I'm sure was down to not using the drier or heating upstairs.
Oh and I'm at home all day.