ULEZ

[niemeyjt]

Isn't noise then the issue - certainly similar systems we had in Qatar were?

[Nomoss]

Isn't noise then the issue - certainly similar systems we had in Qatar were?

I don't know when that was, what type of units you had, or whether they were well installed and maintained, but the new split outside units I just installed are extremely quiet.

[exile]

All of the air to air systems I have seen suffer from one fundamental flaw. The heat is released relatively high up and since heat rises you do not get the direct benefit that an air to liquid system feeding underfloor heating coils.

[Nomoss]

All of the air to air systems I have seen suffer from one fundamental flaw. The heat is released relatively high up and since heat rises you do not get the direct benefit that an air to liquid system feeding underfloor heating coils.

That is true, but mixing the air in the space by directing the airflow from the wall units downwards when heating and upwards when cooling mitigates that problem.

If cooling is not required, floor mounted units are available, which are no more obtrusive than several feet of radiators running along a wall.

Underfloor coils are better for heating in some ways, and do not require such hot water as radiators, making them more efficient.
However, like a radiator system, they are useless for cooling, and, with installation, cost several times as much as a split air/air system.

Probably the ideal solution for those living in cold places, or with plenty to spend on a separate cooling system.

To avoid having multiple indoor units we have one at each end of the house, with a couple of table fans on the floor to move the air towards the other areas. This works well in as there are corridors, few doors, and doors for rooms in use are kept open.

When I was reforming the house I installed grilles in the ceilings and loft floor, connected together through the insulation, so that I could later set up an air filtering and circulating system. I never did so as I decided that the necessary ductwork in the loft would make the floor space there unusable.

In a previous house in Spain, where it was very dusty, I built an air circulating system with an electrostatic filter in the large space above the ceilings. This was also designed to slightly pressurise the interior of the house with fresh air, to prevent dust entering, and worked very well.