I have recently purchased an I -heat and i thought I would share my experience as there a bugger all reviews out there.

After researching many options for central heating I took a leap and went for the iHeat. To give some context we are heating a 140sqm 1930's weather board home with insulation in the walls, ceilings and floors. Windows are single glazed and 70% of them have thermally lined curtains.

Install costs

• We received prices ranging between $8.5 and $10.5k. For our property. This was roughly:
• 20% more expensive than heat pumps that would not have done the job.
• 25% cheaper than gas fired radiators in all rooms.
• 35% cheaper than ducted heat pumps.

Running costs

Therostat running 

• Am Program set to 16 deg fro wak up runs for 2 hours
• 4.30 pm - 9.30pm set to 18 deg
• Weekends we run 50%ish longer
• Running costs for June avg $3.40 per day
• See met service for June temps in Wellington to give this context

Performance

• Notice sound of air movement when fan set to auto and coming up to temp. 
• Once at temp no noise
• Can be set to med fan and no noise at all
• Heat from fan is instant. Edge taken off in 10 min.
• With an outside temp of 10 deg expect half an hour to go from inside temp of 13 - 18 deg

Key reasons for choosing

• I like the idea of not paying for the core "heating machine" I already have a rinnai so like the idea of recycling existing infrastructure which i know will last
• The iheat is just a box with a fan and heat exchanger. Simplicity appeals to me. Less things to go wrong.
• Best price point for central heating. I quite easily was able to get a rough idea of cost of materials for the instalation of ducting, iheat etc. Give the time it takes to install i feel like a price of 8.5k is pretty fair for both the home owner and the installer

Other Notes

• We are warm all the time and love it.
• Have the ability to add a nest thermostat or alternative latter to make it a wifi/smart system.
• I found a bunch of industry people slagging off the Iheat. These people were quick to offer an alternative. I started to serious look at the iheat after one of the guys quoting on ducted heatpump recommended the iheat with respect to the budget I had available. Also found two plumbers who had installed themselves and approved

Hope that is useful to someone. 

do you have bottled gas or connected to the street?

On the street 7.5c p/kwh

so might not be anywhere near as good on bottled.

You will need to crunch some numbers. My understanding is the cost per kwh is more expensive but you save on lines charges