Heat pump tumble dryer - do they create condensation and how long is a typical program for fully dry

Weave

Thanks everyone for your input and info on drying times etc. This has been a really helpful excercise for me to work out what to do next.

I decided to crunch the numbers for my specific case. The following is sort of for my reference to look back on as I am not expecting to sort this until the January sales start but others may find it a useful example of the savings to be made.

I have assumed the manufacturers quoted energy usage figures are realistic.

I currently pay 48.44 per kWh (Dec 2022) (I GOT THIS RATE WRONG, IT SHOULD HAVE BEEN CALCULATED USING 31.44 AFTER ALLOWING FOR PRICE CAP DISCOUNT - SEE CORRECTION ON PAGE 4 OF THREAD )

I estimate we do 6 full dryer loads per week or 312 per year

My existing dryer is a Tricity Bendix TM 320 W Dryer and is only designed for 5kg but we regularly put more in it than that and have always done so. The quoted kWh for 5kg to dry is 3.64 but I estimate this to be more likely 6kWh for larger loads if not more now it is so old and inefficient.
Cost per load £2.91 estimated
Cost per week £17.46
Cost per year £907.92 estimate

As we have a width restriction for the new device it has to be less than 60cm wide to fit the gap in the units. I am therefore considering narrower dryers only:

For Heatpump option - Hotpoint NTM1192SK Dryer (9kg) - for around £429 (plus delivery) at the moment - Full load to dry is 2.13 kWh - £1.03 per load
Cost per week £6.18
Cost per year £321.36
Saving over old dryer per year £586.56

For a vented option - Hotpoint H1D80WUK Dryer (8Kg) - for around £259 (plus delivery) at the moment - Full load to dry is 5.02 kWh - £2.43 per load
Cost per week £14.58
Cost per year £758.16
Saving over old dryer per year £149.76

I am surprised at how much cheaper the heat pump option is to run and I have seen some that consume even less energy than the above Hotpoint. My mission now is to locate a dryer that is 59.5cm wide and has the lowest energy consumption and the best reviews!

Alnat1

Hope you can find the perfect model, good luck 

macman

I'd look at spending a little more and getting maybe a mid-range Bosch? Hotpoint is a budget brand of Whirlpool, with all that implies.
Obviously the width restriction is a limiting factor, but there must be options other than Hotpoint?
12m warranty only, unless you can find a Hotpoint at JL. Bosch: 24m as standard.

daveyjp

The Hotpoint looks to be energy hungry, is that the maximum figure?

Our new Bosch condenser only uses 2-3 kw per load based on a 1400 rpm washer spin cycle.

With the extended drying time of heat pumps how you expect to dry the loads over the  week is an important consideration 

If you are doing a load a day it will be fine.  If you expect to do 3-4 loads in a day it will be on 6-12 hours.

Weave

macman said:

I'd look at spending a little more and getting maybe a mid-range Bosch?

My initial thoughts were that the mid range brands were pricey but that was before I realised how much energy we would save after doing the calculations so I will look at more expensive options now.

daveyjp said:

If you are doing a load a day it will be fine.  If you expect to do 3-4 loads in a day it will be on 6-12 hours.

That is a concern. At the moment I try and smash through the loads in one to two days doing 2 hourly load changes. I may have to adjust my routine to evening and morning loads but we can do that now as I won't have to leave the back door open to vent the condensation anymore.

Cirrus1

On the John Lewis website you can filter by weight. Perhaps the lighter machines are a bit smaller.
There are days that I do many loads and I don’t pay much attention to how long it is taking. I’m sure I would have noticed if took an excessive amount of time.

Mstty

Weave said:

Thanks everyone for your input and info on drying times etc. This has been a really helpful excercise for me to work out what to do next.

I decided to crunch the numbers for my specific case. The following is sort of for my reference to look back on as I am not expecting to sort this until the January sales start but others may find it a useful example of the savings to be made.

I have assumed the manufacturers quoted energy usage figures are realistic.

I currently pay 48.44 per kWh (Dec 2022)

I estimate we do 6 full dryer loads per week or 312 per year

My existing dryer is a Tricity Bendix TM 320 W Dryer and is only designed for 5kg but we regularly put more in it than that and have always done so. The quoted kWh for 5kg to dry is 3.64 but I estimate this to be more likely 6kWh for larger loads if not more now it is so old and inefficient.
Cost per load £2.91 estimated
Cost per week £17.46
Cost per year £907.92 estimate

As we have a width restriction for the new device it has to be less than 60cm wide to fit the gap in the units. I am therefore considering narrower dryers only:

For Heatpump option - Hotpoint NTM1192SK Dryer (9kg) - for around £429 (plus delivery) at the moment - Full load to dry is 2.13 kWh - £1.03 per load
Cost per week £6.18
Cost per year £321.36
Saving over old dryer per year £586.56

For a vented option - Hotpoint H1D80WUK Dryer (8Kg) - for around £259 (plus delivery) at the moment - Full load to dry is 5.02 kWh - £2.43 per load
Cost per week £14.58
Cost per year £758.16
Saving over old dryer per year £149.76

I am surprised at how much cheaper the heat pump option is to run and I have seen some that consume even less energy than the above Hotpoint. My mission now is to locate a dryer that is 59.5cm wide and has the lowest energy consumption and the best reviews!

48.44p kWh? Is that a day rate for economy 7?or some other reason it is that high?

Weave

Thanks for highlighting this @mstty. My bill shows the rate as 48.44 in a summary box but when I look at the itemised lines it shows:

Energy Used XXXX kWh @ 48.44p/kWh
less Energy Price Guarantee XXXX kWh @ 17.00p/kWh

My actual price capped rate is 31.44 per kWh. Does that sound more reasonable?

Mstty

Weave said:

Thanks for highlighting this @mstty. My bill shows the rate as 48.44 in a summary box but when I look at the itemised lines it shows:

Energy Used XXXX kWh @ 48.44p/kWh
less Energy Price Guarantee XXXX kWh @ 17.00p/kWh

My actual price capped rate is 31.44 per kWh. Does that sound more reasonable?

That sounds much better you can double check your regional figure below.

Might make a difference to your calculations

https://www.gov.uk/government/publications/energy-price-guarantee-regional-rates/energy-price-guarantee-regional-rates

SnakePlissken

daveyjp said:

The Hotpoint looks to be energy hungry, is that the maximum figure?

Our new Bosch condenser only uses 2-3 kw per load based on a 1400 rpm washer spin cycle.

With the extended drying time of heat pumps how you expect to dry the loads over the  week is an important consideration 

If you are doing a load a day it will be fine.  If you expect to do 3-4 loads in a day it will be on 6-12 hours.

My Bosch heatpump  says 2kw for a  full cotton load in manual. ( thats the longest program)

In reality i think we are around 1kw to 1.5 kw per full load for cotton. (We do a 1400 spin on washing)
I think for some loads we are far less eg shirts load where its 45 mins or less to complete.

Secret to max out low energy use is seperately  dry towels,  shirts, cottons, man made fibres etc on correct program for them. Or if not much of a load use mixed mode which is 1.5 hours, but generally is under that, sometime under 1 hour.