Nibe Fighter 360p ashp costing me loads to run

ra200

Any one have a nibe fighter system? if so what are your thoughts on it.

I have a nibe 360p in my 3 bedroom Melin homes house and the system is very very expensive to run i have done a lot of reading up on the system and know the system like the back of my hand i have been in contact with nibe, At the moment it is cost me around £13.00p a day to run in the winter as it is using 85 units a day. I have now been trying to speak to some one at Melin homes about this system but i can only get though to reception and they just give me some rubbish about we will forward your infomation to our repairs department so i guess they are trying to ignore me.

Even on the energy trust website on air source heat pumps it says the following below

http://www.energysavingtrust.org.uk/Generate-your-own-energy/Air-source-heat-pumps

What fuel will you be replacing? The system will pay for itself much more quickly if it's replacing an electricity or coal heating system. Heat pumps are not recommended for homes on the gas network.

So why the heck did they install a air source pump in the house i live in if we have mains gas in the house?.

albyota

Hi, is the unit itself using 85 units a day, or is that the total meter reading of all your electric per day?
What part of the UK are you? Temps?

ra200

The units i am quoting are for the nibe system only and i am in south wales in a brand new house with underfloor heating and pleanty of insulation,

The system uses 25 units of electric a day in autumn/spring mode (in this mode the air pump is running and the compressor and fan are running but the immersion heater is blocked) and it hardly heats the house then the system uses in the correct winter mode for this time of year around 85 units a day in the winter mode(air pump running and the compressor and fan are running and auto-immersion heater enabled)

albyota wrote: »

Hi, is the unit itself using 85 units a day, or is that the total meter reading of all your electric per day?
What part of the UK are you? Temps?

ra200

I have put the high usage down to the immersion kicking in but if you disable it the house is freezing.

albyota

My system is the Mitsubishi 8.5 kW Ecodan and is fitted in a four bed detached running UFH, it has been using on average 45 - 55 units per day (£4.50-£6/day) throughout this cold spell, there is no electric backup element, but I'm running it at a low temperature of 40 degrees, it does the hot water twice a day. house is toasty. I suspect that it is the colder temps pulling in the electric heater to assist, but as you are not warm either the unit is incapable of working at capacity at very low ambient. I agree if there is gas on site...they should have used it, or fitted something that can cope at lower temps.

albyota

silly questions, are you running the UFH all day with night set back on room stat/s?
Have the UFH manifolds blending valves been set up correctly? / Balanced? Is it Zoned?

ra200

I have put it down to the nibe 360p ashp can not cope well with the temp below 8c,

There are are few modes i can put the system in to

Autumn/spring mode (in this mode the air pump is running and the compressor and fan are running but the immersion heater is blocked)

Winter mode(air pump running and the compressor and fan are running and auto-immersion heater enabled)

Summer mode ( in this mode the air pump is blocked and the compressor is off and fan & immersion heater is blocked)

The system has a outdoor sensor and i can also set up auto mode this is the temp the immersion will stop kicking in and the temp the compressor will cut out

albyota wrote: »

My system is the Mitsubishi 8.5 kW Ecodan and is fitted in a four bed detached running UFH, it has been using on average 45 - 55 units per day (£4.50-£6/day) throughout this cold spell, there is no electric backup element, but I'm running it at a low temperature of 40 degrees, it does the hot water twice a day. house is toasty. I suspect that it is the colder temps pulling in the electric heater to assist, but as you are not warm either the unit is incapable of working at capacity at very low ambient. I agree if there is gas on site...they should have used it, or fitted something that can cope at lower temps.

ra200

I keep the living room and kitching stats at the 21c mark and the bedroom ones at 21c the UFH is running 24/7 I was told UFH manifolds blending valves have been set up right but if they are not i would not know if they where wrong,

albyota wrote: »

silly questions, are you running the UFH all day with night set back on room stat/s?
Have the UFH manifolds blending valves been set up correctly? / Balanced? Is it Zoned?

albyota

hmm, try dropping the bedroom stats down to 19 C, this is a fine tuning thing I think, the system runs on propane gas as its refrigerant, the unit also relies on return ventilated air from within the house....which you are trying to heat, is there any fan speed adjustment on the return fan, or baffles within each room you could turn down? Also because it is pulling in very cold air from outside can you reduce or minimise the amount, als what temperature are you keeping the tank at?

ra200

There are 3 Air ducts one in the bathroom one in the kitchen one in the shower room also i have been told to keep the trickle vents above the windows that have not got ducts open,

The fan has got three setting speed 1 speed 2 and normal,

The Nibe is trying to keep the tank at 55c in winter mode if i switch the system to Autumn/spring mode so the immersion heater is blocked the temp stays at about 25-35c

albyota wrote: »

hmm, try dropping the bedroom stats down to 19 C, this is a fine tuning thing I think, the system runs on propane gas as its refrigerant, the unit also relies on return ventilated air from within the house....which you are trying to heat, is there any fan speed adjustment on the return fan, or baffles within each room you could turn down? Also because it is pulling in very cold air from outside can you reduce or minimise the amount, als what temperature are you keeping the tank at?

albyota

ra200 wrote: »

There are 3 Air ducts one in the bathroom one in the kitchen one in the shower room also i have been told to keep the trickle vents above the windows that have not got ducts open,

The fan has got three setting speed 1 speed 2 and normal,

The Nibe is trying to keep the tank at 55c in winter mode if i switch the system to Autumn/spring mode so the immersion heater is blocked the temp stays at about 25-35c

unless you are in danger of suffocating, I would suggest in this cold weather the trickle vents are only open a fraction, and try the fan speed on 1, to me, it seems as if you are pulling in too much cold air from outside, and sending it across the internal heat exchanger too fast, the bathrooms are not in use all the time so there is no latent heat from moisture to recover (MHRV). Give these things a try, but remember what settings it was on so you can put it all back if no better. good luck