This heater gave my wife and I a terrible headache straight away. The smell of gas was so strong it made us feel sick. The heater itself is very hot and heats well but we had to return it after becoming sick. Go get yourself a $79 panel heater in masters and it will do a great job without the smell.
Very warm
Terrible smell of gas

I got it yesterday, timers set, house warm... I've got a large area to heat so was concerned about how far it would reach. Step outside for a moment and you really know its working...

It does have a heating noise at times (just an expansion in metals I suspect), but I'm sure it will die down as the heater settles into it new home.

Im very happy with it...
Size, heating capacity, weekend timers were also a plus..

We bought this heater to heat our fairly cold house. We have a large open area - bigger than is recommended - and it still does a great job heating the house. We use the two timers through winter morning and night. It is fairly quiet and efficient and has been a fantastic purchase.
Efficient

This unit worked for 30 mins and then a flurry of fault modes starting with Fault 18 (temp sensor) and then Fault 12 (incomplete combustion). I really expect better QC and fewer issues from Rinnai.

I guees now I have to waste my time taking it somewhere to get fixed and them lose my heater just prior to winter.... or Rinnai can send someone over to restore my faith in Australian Manufacturers.

Let's see how this plays-out. If this gets sorted quickly, i will removce this post. If otherwise, I will get my money back and go for another brand.
Good exterior design
Immediate faults, stops working by itself, several faults codes which can only be fixed by a technician

Excellent gas heating compared to reverse cycle split system air-conditioners and much more economical in running costs. If you don't mind the noise and hot air being blown in your face, then it's defintely 5-star rating. I'd vote it 4-star otherwise.
Reputable brand, low emission (half the allowed limit of no2), excellent overall heating capacity, modern colour (platinum silver), easy to transport
The fan is a wee bit noisy (compared to radiant heating minus fan) and drafty (hot air being blown in your face).

The first Avenger 25 we had emitted gas odour. After trying to repair the unit for the 4th time, they finally agreed to exchange the unit for a new unit. We have yet to test the new unit as we only got the unit sometime in October / November which was too hot to run a heater!

Overally, service was quite bad. We were told that the gas odour was a result of our cooking odours being sucked into the unit. Tell me, which cooking odour smell like gas?? This was despite the technician initially confirming with his gas meter that there was leakage.
- Heats up large area
- Heats up quickly
- Nice design
- Emits gas odour even in an open area
- Terrible after sale service

I will not recommended it, specially if you have respiratory problems or you have very young kids or very elderly people at home. I returned mine because of the strong combustion gas smell it emits.
Good price, no professional installation required, heats up quickly.
Emits strong gas odor

We bought this new and on the very first use, there were strong gas odours within 15 minutes. Terrible! Even after opening outside doors, the gaseous smell was still strongly evident. I grew up with gas heaters and were aware of the expected gas smells but surprisingly for a current model, the Avenger 25 was unsatisfactory.

I believed all of Rinnai's 'low emmision' features for the Avenger 25 and thought that it would be ok however the gas levels were unnaceptable for us. Do not buy this product if you are concerned about gas levels. Especially if you have unborn/young childern. Not recommended.
Nice design. Flames are internal and not seen.
Very strong gas odours. (Carbon Monoxide and Nitrogen Dioxide. Expensive (rrp $1299)

Heats up very well, easy to use and has features like remote, child lock, economic mode, heats up our large area well, easy to clean. It comes in 2 colours, ours is white, better than electric heater and cheaper to run than oil heaters. Fan is quite, little noise, you need to clean the filters at back, but this is easy with a vacuum.

Can't live without it, well made in Japan.
Keeps us warm !
Has a slight gas smell at firts, but you need to keep good ventilation and then you don't smell it.

Works well in heating our 2 rooms, but now reading the reviews i realise why i have been getting headaches every evening. I notice a slight gas smell, have a window slightly open. We had a very old gas heater which was working fine, no headaches. Wish i had read these comments beforehand, but may call the good guys about the problem.
Easy to use
Slight gas smell

It warms up the room in no time. I don't have to sit right in front of it for warmth like I did with our old bar heater. It turns itself on at the touch of a button. Temperature control is easy and don't have to get up from seat to change temp as comes with a remote. Also has a timer which I have just set, following the manual, so when I get up in the morning my lounge room should be nice and toastie.
Reliable, light weight, easy to operate and efficient.
Have only had the heater for 1 month and so far no cons.

I was really skeptical after reading all the reviews, about it omitting a gas smell. I have over sensitive sense of smell and two small kids... So was concerned for both reasons. It is great .... No complaints.
Gives great warmth, no smell so far and has been a god send in the last month since we bought it.
Good heat in a large space

A quick and easy way to get our open plan living area warm. Got a big lounge, family, dining and kitchen area all open plan with a pitch roof ceiling (kitchen and dining area) and its warmed up these areas within the hour. Quite operation and no smell or odour.
Easy operation with thermostat, that's why we bought this item. Comes with on off timer and tiny remote which we haven't had the need to use.
Easy to operate and does the job nicely.
The gas hose could have been longer. Comes with 1.5 meter gas hose, some other brands have longer hose. But it's easy fixed I guess by buying a longer one.

I was also concerned about the smell issues I had read but we purchased our heater last winter and it has been fantastic. No smell issues at all maybe a slight odor when it is first on and heating up but that soon disappears. My husband and I love this heater it heats our large family/kitchen area which is all glass beautifully. I cannot recommend it enough to anyone wanting a heater for a larger area.
Everything but in particular its effectiveness and its easy use
Cant really think of anything

Modern styling (more floor standing reverse cycle airconditioner than old fashioned gas heater). Oustanding heat capacity and very cheap to operate. I bought two and they heat a 4 bedroom house up and down!
Heat output, automatic safety devices, cost of operation
Timer operation overly complex. Stepped top surface. Not an ex apple industrial designer at work here.

Good value and efficient, would recommend it to any household with big or small area. Well worth the investment and will not disappoint.
We have it for 2 years and found it:
- easy to maintain and clean
- heats up our lounge and rooms quickly considering the heater is approx. 15m from where we were.
- timer works really well
- never had any problem
Fan is a little loud but noise subsides when unit reaches the set temperature.

Avenger 25 gets up to the desired temp in short space of time then the fan speed / noise drops to gently maintain stable temp. Did a fair bit of research beforehand very happy with this purchase, looks good, economy mode, timers etc and no gas smell like the old brigadier burner (2 storey house, newcastle area)
Energy efficient, pumps out the heat, looks good
Nothing yet although It wasn't cheap compared to other makes / models