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richardc1983

Great pics...

How many diff rooms does the fujitsu heat/cool?

How about control? As in are they are all at the same temp or do you struggle to keep them even. Yours is a bungalow too isnt it.

Andy_WSM

richardc1983 wrote: »

Great pics...

How many diff rooms does the fujitsu heat/cool?

How about control? As in are they are all at the same temp or do you struggle to keep them even. Yours is a bungalow too isnt it.

Yes, it's a bungalow. Even temps throughout with an element of individual control. The living room is where the sensor is - it's the biggest room - Inlet & outlet in here. The kitchen is joined to the living room, open plan, but also has an inlet & an outlet. The 2 bedrooms - 1 is in use and the vent is open, but turned down so it's not too cold in there. The other room isn't in use, so the vent is turned down ever further so although there is air moving in the room, it is very little - no point wasting the energy. Inlet & outlet in both. The bathroom just has an outlet, so drags air through from other rooms, which works well and means no cold breeze when you get out the shower!

I also have the system ducted into the conservatory but to be honest - it's not enough in there, although it does make the heat of the day bearable, whereas without it the conservatory is unusable!

richardc1983

Andy_WSM wrote: »

The bathroom just has an outlet, so drags air through from other rooms, which works well and means no cold breeze when you get out the shower!

I also have the system ducted into the conservatory but to be honest - it's not enough in there, although it does make the heat of the day bearable, whereas without it the conservatory is unusable!

So the bathroom just has an extract? How does that go with regards to smells etc? Do you leave doors ajar of do you have grills in the air.

It does seem like a good setup. Are you using the sensor that is built into the controller?

Where conservatories and air con are concerned... heres some advice. Your conservatory is always going to be hotter than outside eg 30C inside and perhaps only 18C outside so while the sun is shining through you are better off using the cooler outdoor air to cool the conservatory by having the doors/windows open and the air con to boost that.

AS soon as the sun moves off the conservatory get the doors shut and let the air con take over.

Free cooling for you!

The problem im having with my system at the moment is its only like 20C outdoors but 22/23 indoors which is a good temp however it has been humid last few days but because it isnt that hot outside the compressor doesnt run because it isnt warm enough.. I only have it set at 22C so its only coming on occasionaly. I have used the "dry mode" but find the room gets too cold then! I could open windows but living by a main road i get noise problems then!

Only way to solve this would be to have a heat recovery unit that brought in fresh air.

Andy_WSM

I've not suffered bathroom smells in the rest of the house, likely down to the volumes of air being extracted from other rooms - i.e. anything is mixed down, a lot! No grills in doors etc, but all of the doors have gaps underneath them and the air gets drawn out through these gaps - you can feel it when you put your hand to the bottom of a door. The amount of air drawn from the bathroom is small, so it's not a rush of air into the room, just a gentle trickle. All the other rooms have inlet & outlet, the pressure is pretty well balanced.

I do open the conservatory windows in the hottest of weather, but to be honest I am quiet lazy about it and usually let the A/C deal, which it always does eventually, just has to work really hard sometimes to get there!

Oh yeah, with regards the temperature sensing - it can either be done at the IDU on the air return or on the controller in the living room - selectable by pressing a button. I find the living room sensor gives the best accuracy, so I leave it on that one all the time - the living room is really where I want to the temperature to be most stable anyway I guess.

richardc1983

Yeh I guess so, do you have ducts to the kitchen?

Are IDU and air return not the same? ASsuming you mean IDU is indoor unit.

Andy_WSM

richardc1983 wrote: »

Yeh I guess so, do you have ducts to the kitchen?

Are IDU and air return not the same? ASsuming you mean IDU is indoor unit.

Yes, kitchen has both inlet & exhaust - very welcome when cooking the Sunday roast!

There IS a sensor on the IDU, but as my IDU is in the loft you wouldn't use it - i.e. it would pick up the surrounding loft temps, whether than be hot or cold. The other sensor is in the manifold where all the return ducts meet - i.e. it is a direct reading of the air being returned, rather than of the IDU. You would use the IDU sensor if the IDU were fitted in a false ceiling void in say, an open plan office. Still, I use neither and prefer instead the sensor on the time controller...

richardc1983

Andy_WSM wrote: »

Yes, kitchen has both inlet & exhaust - very welcome when cooking the Sunday roast!

There IS a sensor on the IDU, but as my IDU is in the loft you wouldn't use it - i.e. it would pick up the surrounding loft temps, whether than be hot or cold. The other sensor is in the manifold where all the return ducts meet - i.e. it is a direct reading of the air being returned, rather than of the IDU. You would use the IDU sensor if the IDU were fitted in a false ceiling void in say, an open plan office. Still, I use neither and prefer instead the sensor on the time controller...

Our office doesnt have return air ductwork only a supply manifold as they use the false ceiling void as the return air and the unit just sucks air from the void. There are however the return air sensors in some of the grills in teh ceiling that are to allow air to move through into the void.

Doesnt work very well as we have fresh air supplied into the void too from the AHU which then mixes with this air so it gives conflicting temps to the sensor.

Andy_WSM

richardc1983 wrote: »

Doesnt work very well as we have fresh air supplied into the void too from the AHU which then mixes with this air so it gives conflicting temps to the sensor.

Ah yes, I can imagine that no allowances have been made for the temperature of the fresh air being injected?

My unit also has a fresh air inlet on the IDU - I have it closed off though. My bungalow already has a couple of air vents which I leave open, so there is always fresh air in here anyway.

Whilst I've been typing this evening I have had my A/C in heat mode, to see if there is a draft as there has been previous years I have tried it in heat mode - and am pleased to say, that no...there is no draft!

Also, the load on my "Owl" has only gone up by 1.8KW, so 8KW of heat out for 1.8KW in - OK, I know it's 16C out, so it's not exactly working hard, but hopefully it's an indication of a more tolerable winter coming up for me!

richardc1983

Andy_WSM wrote: »

Ah yes, I can imagine that no allowances have been made for the temperature of the fresh air being injected?

My unit also has a fresh air inlet on the IDU - I have it closed off though. My bungalow already has a couple of air vents which I leave open, so there is always fresh air in here anyway.

Whilst I've been typing this evening I have had my A/C in heat mode, to see if there is a draft as there has been previous years I have tried it in heat mode - and am pleased to say, that no...there is no draft!

Also, the load on my "Owl" has only gone up by 1.8KW, so 8KW of heat out for 1.8KW in - OK, I know it's 16C out, so it's not exactly working hard, but hopefully it's an indication of a more tolerable winter coming up for me!

Correct I think fresh air comes in at about 20C so just messes it all up.

Thats about the same as what mine uses really. What temperature did u whack it upto though to get that? Its an inverter isnt it?

What type of vents did you have before? Any link to them?

Andy_WSM

richardc1983 wrote: »

Correct I think fresh air comes in at about 20C so just messes it all up.

Thats about the same as what mine uses really. What temperature did u whack it upto though to get that? Its an inverter isnt it?

What type of vents did you have before? Any link to them?

I whacked it up to 30C, it's reached 25C in the living room now - phew! LOL. Yes it's an inverter, just went out to listen to it - the compressor is running reasonably hard, but the fan on the ODU is only on low, so it's obviously able to collect plenty of heat as the ambient air isn't too cold.

The old vents were just round, so not directional at all - they could still be opened and closed by turning them, but that was the limi of the adjustments.