6 months HP data for a passive house

fclauson

Thought you would all be interested - shows primary energy usage of the heating system over the past 6 months

dos30

Very interesting, can you provide more information to give us some context..

Air or Ground Source Heat pump?
Make/Model/Capacity of heat pump?
What was the heat requirement according to the PHPP?
Size of the house, underfloor throughout, temperature settings?

Cheers

fclauson

dos30 wrote: »

Very interesting, can you provide more information to give us some context..

Air or Ground Source Heat pump?

AirSource

Make/Model/Capacity of heat pump?

Danfoss DH APQ 9kw (of which 6 is the immersion which has been on for 1hr in the past 6 months !!)

What was the heat requirement according to the PHPP?

10w/sqm/hr (13 kwh/sqM/year)

Size of the house, underfloor throughout, temperature settings?

3500 sqft/ UFH throughout/ no stats - HP set to deliver
28 degrees liquid at 0 deg outside - building sits at around 21/22 as measured a the MHRV extracts

dos30

Thanks, my setup will be similar but with a heat demand of 19.5 kwh/sqM/year.
I'm also using the same heat pump, albeit under the Thermia Atec name and 15kw.
So it's nice to see some real world stats, 6 months of winter space heating for just over €40 if I read it correctly?
What is the scale on the left hand side of the graph?

Also what are you using for hot water if the heat pump was only needed for 1hr for it?

fclauson

dos30 wrote: »

Thanks, my setup will be similar but with a heat demand of 19.5 kwh/sqM/year.
I'm also using the same heat pump, albeit under the Thermia Atec name and 15kw.

look at spending more on insulation and less on the HP
and
check your electrical supply will take the hit of a 15KwhHP starting (min won't and its a 16kva supply - we get very close to the limit when we hit the h/w boost) and have blown the 63amp fuse on two occasions - the HP compressor takes 40amps on start (for a very very short space of time) - and if you then add in the 6kw immersion plus you cooker, washer ........... BANG

So it's nice to see some real world stats, 6 months of winter space heating for just over €40 if I read it correctly?

check your maths - a unit is say 18c during the day and 6c at night - at peak I was using 12kwh/day - which would be around €1.70 to €2.20 per day - depending on exactly when that 12kw was used

What is the scale on the left hand side of the graph?

sorry - hours run - the online thermia/danfoss site will give you hours run from your HP - my HP uses about 2Kw primary each hour

Also what are you using for hot water if the heat pump was only needed for 1hr for it?

I have just not shown the h/w production (as its fairly constant and hence un interesting) - this is also done via the HP - working out at around 7kwh/day of primary electricity

Tommyboy08

fclauson wrote: »

look at spending more on insulation and less on the HP
and
check your electrical supply will take the hit of a 15KwhHP starting (min won't and its a 16kva supply - we get very close to the limit when we hit the h/w boost) and have blown the 63amp fuse on two occasions - the HP compressor takes 40amps on start (for a very very short space of time) - and if you then add in the 6kw immersion plus you cooker, washer ........... BANG

check your maths - a unit is say 18c during the day and 6c at night - at peak I was using 12kwh/day - which would be around €1.70 to €2.20 per day - depending on exactly when that 12kw was used

sorry - hours run - the online thermia/danfoss site will give you hours run from your HP - my HP uses about 2Kw primary each hour

I have just not shown the h/w production (as its fairly constant and hence un interesting) - this is also done via the HP - working out at around 7kwh/day of primary electricity

I know I've taken the piss before about your heat pump using a lot of units but looking at your figures there its even worse than I thought, its using way too much for a house of your spec and its only the bit about your blowing the main fuse that I'd be getting HPI back to look at the unit if I was you, shouldn't be drawing that much power

fclauson

Can you explain your comments

the house is generally using less than the PHPP suggest ?

On the fuse side - we have investigated - if you get both the Compressor starting (21amps ) and the immersion already running (6kw = 26amps) plus you have some other services active (e.g. ovens, kettles etc) then 21+26+? can bring you upto if not over the 63 that the main fuse board is fitted with

For example just having the 3kw kettle on at the same time the other two are you would have 21 + 26 + 13 = 59 amps and that assumes you are sitting in darkness

Tommyboy08

fclauson wrote: »

Can you explain your comments

the house is generally using less than the PHPP suggest ?

On the fuse side - we have investigated - if you get both the Compressor starting (21amps ) and the immersion already running (6kw = 26amps) plus you have some other services active (e.g. ovens, kettles etc) then 21+26+? can bring you upto if not over the 63 that the main fuse board is fitted with

For example just having the 3kw kettle on at the same time the other two are you would have 21 + 26 + 13 = 59 amps and that assumes you are sitting in darkness

Your house is performing very well it's just your heat pump is not, I have B rated houses using less units than that,
21 amps for the heat pump is shocking, there must be something wrong with it if its drawing that much current, as for the 26 amps for your immersion, you've said it's only been on for one hour,

fclauson

Tommyboy08 wrote: »

Your house is performing very well it's just your heat pump is not, I have B rated houses using less units than that,

how many sq feet ?
mine is 359 and the whole inside sits at around 21 degrees

21 amps for the heat pump is shocking,

on start up

Tommyboy08

fclauson wrote: »

how many sq feet ?
mine is 359 and the whole inside sits at around 21 degrees

on start up

You said 40 amps on start up earlier?

3000sq/ft and also at 21C all day, 3500 units for 12 months including hot water for family of five,
Your on 2700 for the last 6 months when you include hot water

Cavanjack

3500 sqft/ UFH throughout/ no stats - HP set to deliver
28 degrees liquid at 0 deg outside - building sits at around 21/22 as measured a the MHRV extracts[/QUOTE]

Do you not find 21/22 degrees too warm for bedrooms?

badgerhowlin

This is very intresting.

I dont want to de-rail you post
I have a Vertical HP with active bore hole of 138m of activate borehole.
My house is B1 rated(because my HP has its own immerision which is never used, but BER does not allow for that which brought my COP of my HP down)
Average Temp is about 21.5 hot water heated to 51 deg everynight and every 2 weeks heated to 60

My Stats are like this
Month total KW Avg KW
Dec 361 11.65
Jan 374 13.36
Feb 347 11.19
March 395 12.74
April 224 7.47
May 121 3.90

Tommyboy08

badgerhowlin wrote: »

This is very intresting.

I dont want to de-rail you post
I have a Vertical HP with active bore hole of 138m of activate borehole.
My house is B1 rated(because my HP has its own immerision which is never used, but BER does not allow for that which brought my COP of my HP down)
Average Temp is about 21.5 hot water heated to 51 deg everynight and every 2 weeks heated to 60

My Stats are like this
Month total KW Avg KW
Dec 361 11.65
Jan 374 13.36
Feb 347 11.19
March 395 12.74
April 224 7.47
May 121 3.90

What size is your house and what do you mean by 138m of active borehole? Is pArt of it not active?
What size heat pump have you?
Thanks

badgerhowlin

House is 208 square meters
HP is 12KW •Nibe fighter 1245 with 180L tank Combo

the borehole is 150m deep, the 1st 12m of the borehole has no water in it(not active), the rest 138m has water in it(Active borewhole)

fclauson

Cavanjack wrote: »

Do you not find 21/22 degrees too warm for bedrooms?

yes-ish -my girls do home work/play in their bedrooms - we are a bungalow - so it works ok. Also MHRV will fight to level a house temp so setting bedrooms a couple of degrees lower will probably no last

fclauson

badgerhowlin wrote: »

.... the 1st 12m of the borehole has no water in it(not active), the rest 138m has water in it(Active borewhole)

And that is why I did not go for a vertical HP - I failed to find any one who fully understood boring and plugging a HP borehole correctly using the right clays etc (google for more info on this)

What happens if the water table drops 50M !!! - you then have 50M inactive - how does the well level rise and fall during the seasons etc

badgerhowlin

fclauson wrote: »

And that is why I did not go for a vertical HP - I failed to find any one who fully understood boring and plugging a HP borehole correctly using the right clays etc (google for more info on this)

What happens if the water table drops 50M !!! - you then have 50M inactive - how does the well level rise and fall during the seasons etc

Grouting you borehole is expensive. too expensive... (only need to do this if you have a dry hole. And if you do, go horizontally or Air to water ) As long as you have a good flow of water in your Borehole then your fine.(like I do)

My water level doesnt drop too much in the summer 4m MAX but then HP is not on during the summer so it doesnt matter. In winter it will raise 4 m MAX.

My min active needs to be 120m so im good for 18m drop.