High-wall heat pumps for Whangarei homes

A high-wall is the slim indoor head on the wall and an outdoor unit on the other side of it, and nothing heats a single room for less. Two things decide whether it works properly here: whether it's sized to dry the room out rather than just warm it, and how much salt the outdoor unit has to live in.

How much does a high-wall heat pump cost in Whangarei?

Supplied and fitted, a bedroom or single room runs about $2,000 to $2,900. A main living area is $2,900 to $4,200, and a large or open-plan space $3,800 to $5,800. That's roughly 2.5kW, 5 to 6kW and 7 to 8kW of capacity.

The price covers the lot: the unit, brackets, insulated pipework, the condensate drain, the electrical connection, commissioning and the tidy-up afterwards.

What you actually pay comes down to how far the pipework has to go and where the outdoor unit ends up. If it can go on the other side of the wall from the indoor head, the pipework has barely any distance to go, and that is about as cheap as the job gets. Once the pipework has to travel round the house, or the outdoor unit has to squeeze into a tight spot, that's more materials and more hours. The sizing calculator will put a capacity and a price on your own room in a minute, and the cost page goes through what pushes a job up or down.

Where can a high-wall heat pump go in an older villa?

It needs a clear run of wall, up high, with the room opening out in front of it. Aim it into a doorway or across the back of the sofa and it warms the air right around itself, reads that as the room being up to temperature, and backs off long before it is.

That's the hard part in the villas through Kensington and the Avenues, and in the 1950s to 70s weatherboard across Morningside, Woodhill and Otaika. Picture rails, sash windows, a chimney breast and a door in the wrong place usually leave one workable stretch, and it's seldom the tidy one. Take it anyway. A slightly awkward position that heats the whole room beats a neat one that leaves half of it cold.

Above a picture rail is normally fine, and the rail itself is rarely a problem. The real limits are getting the pipework out to the outdoor unit without crossing a window, and keeping the condensate drain falling the right way so you're not left with a stain down the wall. If the room genuinely has no wall for it, a floor console sits at skirting height and heats it just as well.

Sizing a high-wall heat pump for Whangarei damp

Winters here are wet rather than cold, and that changes what you want the unit to do. Half the job is pulling moisture out of the air, because it's the damp that makes a house feel cold and grows mould in the wardrobe corners.

Which is why buying big is the wrong instinct. An oversized unit races the room up to temperature, shuts off, and leaves the moisture behind, so the windows fog again as soon as it stops. Warm and still clammy.

What works is a correctly sized unit holding a low output all evening. It keeps the air moving and keeps wall and window surfaces above the point where condensation forms, so the whole room dries out rather than the metre in front of it. Set it around 19 or 20 and leave it alone.

Older uninsulated walls and single glazing mean a room can want more than its floor area suggests, so the figure gets settled on site against the glazing, the insulation and which way the room faces.

High-wall heat pumps and coastal salt air

The outdoor unit is a copper coil threaded through hundreds of thin aluminium fins, and those fins are how it dumps heat outside. Salt settles on them and works its way in, and once they've gone chalky and started crumbling away from the tube there's less metal left to shed heat through, so the unit works harder for less.

Out at Onerahi and Parua Bay, or along the Bream Bay coast, that's worth spending on: a corrosion-resistant model rather than the standard finish, and the unit on the landward side of the house rather than the elevation facing the water. Inland at Kamo or Tikipunga it stops mattering and a standard unit is fine.

Wherever it ends up it wants air round it so it can breathe, a position off the ground, and somewhere the condensate can drain away. Somewhere a technician can reach, too, or the annual service turns into a ladder over the fence.

Using a high-wall heat pump for summer cooling

It's reverse-cycle, which just means it can run the refrigerant the other way and move heat out of the house instead of into it. So the unit that warms the lounge in July cools it in February, with nothing extra to buy and nothing else on the wall.

It pulls moisture out while it cools, as well, which is what makes a muggy evening bearable rather than just cooler. If cooling is your main reason for buying, the air conditioning page covers the same gear from that angle.

One unit in the living area with the internal doors open carries a surprising amount of a compact house, but it won't turn corners and it won't push heat down a hallway. Where you want the bedrooms done too, a multi-split runs several heads off one outdoor unit, which on a coastal site means one outdoor unit to protect from salt instead of three.

Not sure a high-wall is the right type? The types of heat pump page sets it against a floor console, a ceiling cassette, a multi-split and a ducted system, and heat pump installation covers how the day runs. When you want a number, get a free quote.