The search for the most energy efficient tumble dryers

Coffeekup

greyteam1959 said:

Coffeekup said:

I use one of these in the winter. On the landing hallway above the top if the stairs where the tends to congregate. Clothes/towels are dry within 8 hour's even with the heating off.
A number of people have commented saying what a good idea it is and how good it looks.

Just inherited one of these during my late father's house clearance.
An original 1960s one.

If you have space (especially dead space) which most people do, do t throw it.

QrizB

wittynamegoeshere said:

We used to hang all our clothes on racks indoors, thinking we were saving money and the planet.  We just ended up with very damp air and black mould in many places.

Having dried indoors for years prior to getting a washer-dryer, without those problems, that sounds like operator error.

We also used to have a combined washer/dryer, any drying came out cooked, shrunken and hard.

Having had a washer-dryer for about a decade, that sounds like operator error too.

k_man

Where does a heat pump drier source the heat?

Isn't there a small space heating cost too (if using when the house is being heated), in addition to the drivers electricity use.

Does this work out similar to the extra heating used when drying by hanging indoors?

Petriix

k_man said:

Where does a heat pump drier source the heat?

Isn't there a small space heating cost too (if using when the house is being heated), in addition to the drivers electricity use.

Does this work out similar to the extra heating used when drying by hanging indoors?

Yes, the heat 'gained' by using a heat pump comes from the environment around it. If it's indoors then it extracts heat from the air indoors. However, as long as it isn't vented outside, the heat is not lost but simply recycled inside the house.

Obviously a conventional dryer adds lots more heat to the environment around it so, for condenser dryers, the electricity used does provide some (potentially) useful heating for the home.

The biggest issue with drying washing indoors is that you need to ventilate the damp air, and that lets heat escape to outside. That is prevented with the dehumidifier approach at the expense of more energy being used, but this is also retained as (potentially) useful heat.

While evaporation will have a cooling effect on the clothes, there is no net loss of energy unless the damp air is then ventilated.

grandadgolfer

wittynamegoeshere said:

Air-drying clothes inside is not generally a good idea, unless you have a very well ventilated room.  In some countries they commonly have special drying rooms, which is basically a draughty room, usually on a corner, that's well insulated from the rest of the house.  So you can dry for free whatever the weather.  It also prevents sun-bleaching, which is another issue with drying outdoors.  It's a very good idea, although whether you ever get the building cost back in energy savings is questionable.

We used to hang all our clothes on racks indoors, thinking we were saving money and the planet.  We just ended up with very damp air and black mould in many places.

Also, evaporating water actively cools the air, just like the refrigerant evaporating in an air conditioner or fridge does.  It makes the air cooler, so the heating will be powered on more as a result of all that chilling.  So it's not free, it costs extra on the heating bill at the same time as rotting the building from the inside.

We also used to have a combined washer/dryer, any drying came out cooked, shrunken and hard.  Getting the heat pump dryer was a bit of a revelation, almost everything goes in it so we have nice dry air in the place, soft and fluffy laundry and I have no eco-guilt due to the pretty trivial amount of energy it uses.

When cold outside we dry washing in spare bedroom on clothes horse.....Door closed / window open one notch never a problem with condensation

k_man

Petriix said:

k_man said:

Where does a heat pump drier source the heat?

Isn't there a small space heating cost too (if using when the house is being heated), in addition to the drivers electricity use.

Does this work out similar to the extra heating used when drying by hanging indoors?

Yes, the heat 'gained' by using a heat pump comes from the environment around it. If it's indoors then it extracts heat from the air indoors. However, as long as it isn't vented outside, the heat is not lost but simply recycled inside the house.

Obviously a conventional dryer adds lots more heat to the environment around it so, for condenser dryers, the electricity used does provide some (potentially) useful heating for the home.

The biggest issue with drying washing indoors is that you need to ventilate the damp air, and that lets heat escape to outside. That is prevented with the dehumidifier approach at the expense of more energy being used, but this is also retained as (potentially) useful heat.

While evaporation will have a cooling effect on the clothes, there is no net loss of energy unless the damp air is then ventilated.

Thanks for that.
Seems the wastage with drying is venting the warmth from the dryer, or ventilating the room if hanging clothes to dry.

Condensing or heat pump dryers, or dehumidifiers can mitigate this, but potentially at the cost of electric vs gas heating.

Spies

As promised I've returned with data on the A++ 8kg Logik I bought.

I ran a relatively small load of... smalls a couple of pairs of chinos and 2 shirts. Maximum power I observed was 600 watts, the cycle took 1hr 20 minutes and used 0.6kWh.

SAC2334

wittynamegoeshere said:

Air-drying clothes inside is not generally a good idea, unless you have a very well ventilated room.  In some countries they commonly have special drying rooms, which is basically a draughty room, usually on a corner, that's well insulated from the rest of the house.  So you can dry for free whatever the weather.  It also prevents sun-bleaching, which is another issue with drying outdoors.  It's a very good idea, although whether you ever get the building cost back in energy savings is questionable.

We used to hang all our clothes on racks indoors, thinking we were saving money and the planet.  We just ended up with very damp air and black mould in many places.

Also, evaporating water actively cools the air, just like the refrigerant evaporating in an air conditioner or fridge does.  It makes the air cooler, so the heating will be powered on more as a result of all that chilling.  So it's not free, it costs extra on the heating bill at the same time as rotting the building from the inside.

We also used to have a combined washer/dryer, any drying came out cooked, shrunken and hard.  Getting the heat pump dryer was a bit of a revelation, almost everything goes in it so we have nice dry air in the place, soft and fluffy laundry and I have no eco-guilt due to the pretty trivial amount of energy it uses.

Thanks for that advice as when I lived in a property with no heating  other than one room ,I dried cloths on a jury rigged washing line strung up in the spare bedroom 

.The mould produced on the ceiling s and walls  though after a year or so was intense .

Now I m in a large bungalow with a rear large conservatory with lots of ventilation I can see that will be my drying room hopefully with much less chance of mould growth.. I don t want that back again ever as even painting over it with anti mould paint just slowed its return .

k_man

SAC2334 said:

wittynamegoeshere said:

Air-drying clothes inside is not generally a good idea, unless you have a very well ventilated room.  In some countries they commonly have special drying rooms, which is basically a draughty room, usually on a corner, that's well insulated from the rest of the house.  So you can dry for free whatever the weather.  It also prevents sun-bleaching, which is another issue with drying outdoors.  It's a very good idea, although whether you ever get the building cost back in energy savings is questionable.

We used to hang all our clothes on racks indoors, thinking we were saving money and the planet.  We just ended up with very damp air and black mould in many places.

Also, evaporating water actively cools the air, just like the refrigerant evaporating in an air conditioner or fridge does.  It makes the air cooler, so the heating will be powered on more as a result of all that chilling.  So it's not free, it costs extra on the heating bill at the same time as rotting the building from the inside.

We also used to have a combined washer/dryer, any drying came out cooked, shrunken and hard.  Getting the heat pump dryer was a bit of a revelation, almost everything goes in it so we have nice dry air in the place, soft and fluffy laundry and I have no eco-guilt due to the pretty trivial amount of energy it uses.

Thanks for that advice as when I lived in a property with no heating  other than one room ,I dried cloths on a jury rigged washing line strung up in the spare bedroom 

.The mould produced on the ceiling s and walls  though after a year or so was intense .

Now I m in a large bungalow with a rear large conservatory with lots of ventilation I can see that will be my drying room hopefully with much less chance of mould growth.. I don t want that back again ever as even painting over it with anti mould paint just slowed its return .

Many of us have been drying clothes indoors for years, if not decades, and have no issues with mould.

But it does rely on the drying room having some method of venting, to ensure the moisture doesn't stay in the room.

Mstty

Spies said:

As promised I've returned with data on the A++ 8kg Logik I bought.

I ran a relatively small load of... smalls a couple of pairs of chinos and 2 shirts. Maximum power I observed was 600 watts, the cycle took 1hr 20 minutes and used 0.6kWh.

That's interesting maybe about 1kwh on a full load. 

Be good when you try a full load