Insulate first and the unit can shrink
NZ installers often use a rule of thumb for a room with a 2.4 m ceiling: 120 watts per square metre if well insulated, 140 if average and 160 if poor. A 25 square metre room with poor insulation needs about 4 kW, which points to a 5 kW unit. Insulate it well and the figure falls to about 3 kW, so a 3.5 kW unit may do.
A smaller unit costs less to buy and less to run. If the ceiling or underfloor insulation is thin or missing, get that sorted before you buy a heat pump. Our guide on sizing a heat pump shows the full method. Insulation keeps paying off every winter, whatever heater you end up with.
Many mid-century homes in the city have small separate rooms off a hall. In a house like that, a modest unit in each room you use can work better than one large unit trying to push heat through doorways.
Rural blocks and long cable runs
Many households live just outside the city on lifestyle blocks. Their switchboards can sit far from the room that needs heat, or the heat pump may be for a separate building like a studio or sleepout. A longer cable run takes more time and materials, so the price will be above the standard install.
Ask the installer to check where the switchboard is and how the cable will get to the unit. If the property has its own supply to an outbuilding, mention it, as it may change the work.
On a farm or block with its own power poles or an older supply, the electrician may want to check the supply first. Any upgrade there is separate from the heat pump, so ask for it as its own line.
Travel time is part of the price on a rural job too. A firm based on your side of the city may charge less to get there, so ask how they work out travel.
Price help among the 28 local installers
Of the 28 installers we track in Palmerston North, 16 give free quotes and 3 offer finance. 4 mention Warmer Kiwi Homes, a national EECA programme with grants that can cover part of the cost of a heat pump for eligible owners. EECA's records link each grant to whether the household has a Community Services Card or SuperGold Combo card and to how deprived its area is.
Check whether you qualify on EECA's website and read our heat pump grants guide before you book a quote visit.
Finance can spread a ducted system or a multi-room job over time. Compare the total you will repay, not just the weekly amount, with the cash price in the quote.
Questions to put to a Palmerston North installer
11 of the local installers fit ducted systems and 5 fit multi-split systems. 14 offer servicing and 10 take on repairs. Use these questions to get quotes you can compare, and read our guide to ducted vs high-wall heat pumps if you are unsure which type to ask for.
Ask every installer the same questions and write down the answers. Then put the quotes side by side: the same size, the same type and the same extras should cost roughly the same, and any big gap is worth a follow-up call.
- What size do you recommend, and how did you work it out?
- Would insulating first change the size you suggest?
- How far is the switchboard, and is the cable run included?
- What is included beyond a standard install? Our cost guide lists the usual extras.
Compare every installer on the Palmerston North page, or read 10 Best Heat Pump Installers in Palmerston North.