I have an axis 24 that came with an instant on hot water system. We are very unhappy with this xystem. When showering if you try to mix in cold water with the hot, the hot water shuts down. We would like to replace this system with a good old fashioned 6 gallon gas/elect waterheater. Any adviseoutthere?.
I have the same hot water system. It is not an instant hot water system but rather a continuous hot water system. You need to set the high temp setting (mine is set at 108 since my wife likes hotter water). Once the hot water starts flowing hot, slowly adjust it with the cold in very small increments until it suits you. You will then have UNLIMITED hot showers as long as your propane holds out. I had to watch a You Tube video on how the system works in order to work it properly. I too like you was frustrated with it until I learned HOW the system works and now I love it. No more running out of hot water. I would not go back to the old style 6 gallon water heater system.
As an added bit of help:
If you open the access panel that is between the fridge and the closet, you can easily see the heater. On the bottom there is an easy to turn valve. Do NOT leave the valve all the way open. Turn it all the way off, then all the the way on, and decide about where the middle setting would be. Set it at the middle-ish.
This took us from pure hate for the system to never thinking of it again.
By using the hot water shower valve solely and having adjusted the heater flow valve, we have no complaints with our now 'continuous' hot water.
The valve on the heater flow is the answer. Water going too fast through the heater caused surges in temperature that made it impossible to regulate final output/pleasant temperature.