Fujitsu Lifestyle Questions & Answers (page 3 of 3)

Unknown

I have the 7.1kW model and it really depends on which mode you use and what the temperature is outside. On the lowest fan setting in energy saving mode it's usually around 50c per hour, but when my husband puts it into turbo mode it can get up to around $1.50-$2 per hour. But we usually have it on a low setting because I don't like it blowing too much.

At colder temperatures, where the outside unit coolant temperature is below freezing (where it is near 0oC or below outside), the unit collects ice on the compressor coils and has to stop heating to defrost the outside coils (because it become ineffective at transferring heat to the coolant which is condensed to heat the inside air) and restore the ability to transfer a usable amount of heat from the outside air to the coolant, and from there use the it to heat in indoors. When it does that, it shuts down the blower inside, since there is no or little heat residual. Once the outside coils are defrosted (don't know if the unit can sense that or just goes through a fixed time cycle) by the electric heating elements in the outside unit, it restarts automatically. It will periodically go through this cycle as ice continues to build up. At the times it is going though these cycles, it is much less efficient and may be more expensive (i.e. use more electricity for a unit of heat) to run than an all electric space heat. I have not been able to get the information from Fujitsu on the efficiency at low temperatures, so do not know at what temperature point the unit is more expensive to use for heating the a $15 electric heater (it doesn't depend on the price of electricity, since electricity is used in both processes, but does effect the cost benefit of the unit.

It's just making sure not to blow cold air at you and defrosting, it's completely normal and you can buy a base heater that uses a little electricity to help keep the units a bit warmer and may help with this a little.

Hi Ian
Unfortunately there are no other instructions that I'm aware of. The ones provided are complicated, but that's all that is available.

Units for Melbourne temperature is in degrees Celcius or degrees Centigrade (°C). No idea about Part b of your question - sorry! (What would that indicate? Why would you need that info? - just trying to understand the rationale there)

Thanks Vic. My reference to 'the units' should have been 'the unit's', that is the ASTG09KMCA. The seasonal coefficient of performance (SCOP) is an annual measure of the efficiency of the unit for a particular climate (i.e Melbourne for instance). Each local climate can have a different SCOP and each different reverse cycle unit with the same COP (coefficient of performance, which may be calculated for the most efficient temp for the unit, but not the average or range the equipment may encounter in the heat sink (i.e. the outside air temp and humidity) A reverse cycle unit has a different SCOP in each specific climate. In rating the reverse cycle units in the EU, they use two 'standard' climates, one where the average low is 2oC and one where is is -2oC, which may not cover all climates, but does give an idea for most climates in AU near sea level (90% of AU population). The calculation will give the annual total electricity the unit will use for a 'standard' installation, but does not vary on the particulars of the room/unit installed in, such as insulation, air leakage rates, and window area (i.e. heat loss/gain of the particular living space). With this SCOP information, one can calculate the total electricity used for the 'standard' living space to give an idea of how much electricity it would take to heat and/or cool their space and indicate what savings could be gained by installing the unit instead of using a electric heater or a gas heater. In my case I was only interested in the heating SCOP because I have a ground floor unit with morning sun and can get along with fans on hot summer days (last year their were no days over 40oC in Melbourne I believe). Also at some temperature the unit may not be efficient enough to use because it costs more to get one unit of heat out of the air, in which case one would want the unit to turn off and instead use a electric space heater or gas heater (depending on availability and relative prices). None of this information is available from the current consumer 'information' required to be included by the manufacturer to sell these units in AU, although it is required in the EU and I assume many other countries. For my space, I calculated I use an additional 2100KWH of electricity in the cooler months, which would mostly be heating (a bit more lighting and a bit less refrigeration electricity). To justify installing a unit for $2000, I would have to save more than 10,000KWH of electricity to cover the cost which would take more than six years if it had a SCOP of 5 (using 1/5 of the electricity of an electric heater, saving ~1600KWH/year at $0.20/kwh (off peak electric price currently about $0.128/kwh) and no imputed interest on the money sunk into installing and no servicing costs). If the reverse cycle unit has a SCOP of heating of 2 (even though it has a cop of 4.9) and imputed some lost interest on the money invested in installing the unit, and some maintenance, it may take 15-20 years to pay for itself, way beyond the 5 year guarantee of the unit, therefore not be worth the effort.

I bought my Fujitsu through Good guys.

Mr stoves is cheaper than the good guys

Apparently the Model number I quoted (unbeknown to me) combined both the Outdoor unit and the Indoor units. The system was installed on April 4 and we're very, very happy with it so far - as well as the quality of the local installation and overall cost..

The model we have is the 5KW and we use it on low to cool a large kitchen dining and lounge area. It could also be used on high if required. Certainly the 7KW would cover this area very well. Hope this helps.

I can't honestly answer that question, as our whole cabin is only 8m by 4.4m. We get the benefit of the cool air in both the bedroom and bathroom, the two farthest rooms from the unit when the door to them is open. And it keeps the cabin cool, even thought it has very limited insulation and very high ceilings. We set it to 23* so not on cold but we certainly notice the difference from the outside temperature! I hope this helps.

The "open plan" kitchen-dining-living room we have it in is approx10m x 10m and it can easily fill with cool air on the medium to higher settings.

"It depends" ... the worst case scenario per day is 2.04kW*(cost of power)*(hours of use)/(duty cycle)

One possible example to solve this equation for a full days use is 2.04kW x 28 cents (per kWh) x 24 hours (run time) / 25% (duty cycle) (assuming it runs at around 25% load most of the time - this will vary on your installation, heat load, number of people, insulation, sun angle, window coverings, internal heat dissipation and inputs etc.)

In the above scenario - one solid 24 hour day of use at 25% duty will be around $3.50 ..... but could be as high as $14.00 if it was running flat out all the time. It could also be as low as $1.00/day if it was only running at night ....

I too have just purchased two myself, you have to remember that very few happy people leave reviews. Reviews are usually swayed by people who are upset and need to vent (nothing wrong with this). I have had a few Fujitsu units (ducted and split) in the past and never an issue.... not one.... However I have no experience with this model and will leave a review after it is installed.

Remember to do your research on the installer and don't go with the cheapest. The best system installed poorly will function worse than a cheap system installed correctly.
"It's not the machine that heats and cools your home, its the person who installs it"

Yes, you can but you will have to get zoning (isolating) solenoids installed in each room so as to zone them, unless you want to cool down the rooms together, which is not very economical.
The size of the outdoor unit (Keating/cooling capacity in Kw) depends on the size of each room.
The Unit you have mentioned will suffice probably only one room.

the answer here is incorrect. you cannot connect two indoor units to one outdoor unit unless it is a multi head type outdoor unit designed for this. these cost more than two separate units and are only used where space for outdoor units is limited, such as on the balcony of a unit.

I have had a multi head air conditioner and in the long term I would not recommend it. When it worked it was great but now that it has died during a heatwave, I have no air conditioning at all in any of the bedrooms. If you have separate units you dont lose everything. It actually worked out cheaper for me to buy 3 separate units rather than replace the original triple header.

NO NO NO - It depends what your room temp is at that moment.
Please renew the batteries in the hand held remote to a good quality Lithium type ASAP. Re-enter the time & day info. Switch on the air con with the remote & ensure it is set to Auto Mode, Auto Fan, Low Outdoor Unit Noise & Economy Mode. Only adjust the set temp range up or down as required. If necessary on a very hot day, set the temp to 18 deg C on start up & then after 10 mins switch back to Auto Mode for desired temp. Similar set to 30 deg C on a very cold day & then after 10 mins switch back to Auto Mode for desired temp. Using Auto Mode for the outdoor compressor unit will modulate the speed / power of the compressor as it nears the set temp. thereby saving money. Similarly using Auto Mode for the indoor head unit fan will modulate the fan speed / power as it nears the set temp. thereby saving money. This is how I operate all my 4 air con units. Bravo Fujitsu, keep it up.

All very confusing.
Why not be able to have "Cool Mode" or "Heat" - "Low Fan" - "Economy mode" and set the fan speed to whatever
instead of all the fiddle.
I have an 8-year-old Chinese model in the lounge and that's all I do with that though it doesn't have the economy mode
and if I turn it down to 18c I think it would throw ice blocks at me.
Not impressed.

The answer that begins with "NO NO NO" has some good info but may not help get your room to temp quickly.
Auto fan is good, however auto "mode" can occasionally swing from heat to cool, Weather set to heat, cool or dry, the system will only run at the speed required. Select your mode and the temp want and then press the "powerful" button, It will basically put the unit into overdrive and ignore the set temp for about 30 minutes, after this it will revert to the previous settings.
Settings such as economy or "low noise" limit the outdoor units operational capacity to about 70%, good when your comfortable, not the best when you need the extra capacity.

R32

natural gas type

r32

My installer did not like the connections but this is not to say they could be unreliable... The connections could be removed and wealded if nessesary!

I have had problems both with the KMCA series compression fittings and with Fujitsu honouring warranty callouts re this issue. I, and all the other installers i know, cut the fittings off and silver solder the pipes together as gas leak issues are very costly and inconvenient.