Rinnai HOTFLO Electric Storage Questions & Answers

Hi - I have a Rinnai HOTFLO electric water heater purchased via Origin about a year ago, model HFE160 (160 litres). It works fine but the thermostat setting is too low by a few degrees, the water is warm and not hot, something I'd like to correct now that it's winter. It takes about 5 minutes for warm water to come out of the kitchen tap when is should be hot, the shower water is warm but was not a problem in the summer. The only question I have is how can I as a user increase the temperature setting without having to arrange a serviceman to come do it at a cost. I live in Oxley Brisbane 4075. Thanks. Peter

After receiving our latest Power bill we went "Shock horror" at the increased amount of power our hot water usage was. We have a 400L Rinnai Hot flow Storage heater that is only 18mths old. There are only 2 people living in the house. In the last quarter our usage has increased by 2000kwh, from 347kwh in the previous quarter to 2343 kwh. Something very wrong here. My question at this stage is what happens if the licenced installer has connected the wires the wrong way around, even though it has worked fine, would this cause a higher power consumption over time?