Heat pump / inverter DIY

anthonykeates

Very helpful post Andy - good to get some feedback from people using these systems to heat a house. What's "IDU" by the way?

Andy_WSM

anthonykeates wrote: »

Very helpful post Andy - good to get some feedback from people using these systems to heat a house. What's "IDU" by the way?

Sorry, "IDU" - In Door Unit. In a split system it would be the bit on the wall in the living room. In a ducted system, like mine, it is the bit in the loft which has all the ducting connected to it.

I'll try and add some pictures to the thread in the week.

Heat Pumps are the future of heating, no doubt, we will soon run out of gas etc, but have other, sustainable, ways of generating electricity to run heat pumps systems.

anthonykeates

In-door unit - I should have thought of that!

richardc1983

Indoor units in the trade are referred to as fan coil units.

stevehead

Andy_WSM wrote: »

Just thought I'd add to this thread as I have found it very interesting.

I am in the SW UK and have a whole house ducted Fujitsu inverter A/C system which I use to heat & cool the house.

Hi Andy, and thanks for your contribution to this thread.
Any chance you could give us an indication as to how much gas was costing you before you went ashp?
As there's no 'official' method of comparing apples with pears (gsh to ashp) that's acceptable to Forum Readers then more anecdotal evidence is required to get a feel for the before/after running costs.
And...
What is the model of the Fujitsu's you are running?

Thanks,

Steve Head

Andy_WSM

stevehead wrote: »

Hi Andy, and thanks for your contribution to this thread.
Any chance you could give us an indication as to how much gas was costing you before you went ashp?
As there's no 'official' method of comparing apples with pears (gsh to ashp) that's acceptable to Forum Readers then more anecdotal evidence is required to get a feel for the before/after running costs.
And...
What is the model of the Fujitsu's you are running?

Thanks,

Steve Head

Hi Steve, yes, that's a good question. My gas bills used to be ~£260 in the Winter quarter. However, it is hard comparing apples with apples even now for several reasons:

My GCH boiler 3 years ago was a 30 year old back boiler, so you can imagine it wasn't very efficient! It used to also provide the DHW.

I am spending now between £2 & £2.50 a day on electricity to run the ASHP. £3 - £4 if the weather is really cold. (See attached pic of energy meter, reset last night)

I also spend approx £30 a month heating hot water only by gas - and running a gas cooker, but I am no chef so it isn't used much!

So in real terms I have seen no increase in my bills despite the horrendous price rises in fuel. I keep my ASHP running 24/7 at the moment and the indoor temp is set to 21 or 22C depending how I feel - never lower, sometimes higher!

The part number of the outdoor unit is: AOY24LMAKL. The indoor unit is a little harder to access as it is in the loft.

Again, hope this helps. I am perfectly happy to answer any more questions if it helps others make an informed decision rather than a best guess.

richardc1983

Excellent ANdy!

Your spending about the same on your heating as I am doing using an LG Multi split, 2 indoor units and 1 out door unit. Total capacity approx 8kw the same as yours.

I do find that with only one unit running though I am spending £3 a day in todays temperature if left running all day and switched off at night.

Heres a link to your specs but I assume the indoor unit is the same as listed in this link as it is ducted...

http://www.ultimateair.co.uk/pdf/Jan%2007%20Update/Current%20Single%20Split%20Service%20Manuals%20Mar06/Ducted%20+%20Universal%20Concealed%20Units%20Service%20Manuals/ARY18-24L%20Service%20Manual.pdf

Andy_WSM

richardc1983 wrote: »

Excellent ANdy!

Your spending about the same on your heating as I am doing using an LG Multi split, 2 indoor units and 1 out door unit. Total capacity approx 8kw the same as yours.

I do find that with only one unit running though I am spending £3 a day in todays temperature if left running all day and switched off at night.

Heres a link to your specs but I assume the indoor unit is the same as listed in this link as it is ducted...

http://www.ultimateair.co.uk/pdf/Jan%2007%20Update/Current%20Single%20Split%20Service%20Manuals%20Mar06/Ducted%20+%20Universal%20Concealed%20Units%20Service%20Manuals/ARY18-24L%20Service%20Manual.pdf

That's the one

Yours was the post with the 2 Splits, one up, one down wasn't it? If it was I'd guess your heating costs are higher as you are in a house, I am in a bungalow - although my property is detached, so subject to weather from all sides.

I must try setting the "set back" timer sometime. It will automatically turn the A/C down at set times to save power. But like I said, I've not had an issue with big bills since I had this unit, so no incentive to try and economise further and possibly feel the cold!

richardc1983

Mine is a split system however its 2 indoor units to one outdoor unit. Its a victorian house but is bigger tahn a one up one down. Originally it was a 5 bed property but is now converted to flats. Ive got the entire ground floor, has the usual characterisitcs of victorian house. High ceilins no insualtions etc!

Andy_WSM

richardc1983 wrote: »

Mine is a split system however its 2 indoor units to one outdoor unit. Its a victorian house but is bigger tahn a one up one down. Originally it was a 5 bed property but is now converted to flats. Ive got the entire ground floor, has the usual characterisitcs of victorian house. High ceilins no insualtions etc!

Ah, then mine is relatively efficient as I have full double glazing, cavity wall insulation and about 6" of loft insulation. The outside temp is just under 4C right now and the ASHP is running about a third capacity - i.e. drawing just 1.1KW of power to heat the whole house to a toasty 23C.

I'll never go back to gas central heating