There is one aspect that divides all the brands, models and sizes on the market squarely into two camps. And that, somewhat ironically, iselectricity.By adding a small (like really small) amount of 🔌 electrical supply to an instantaneous gas geyser, we can benefit in two ways:
If we stick a blower into the combustion chamber of a normally aspirated engine and we apply a little bit of elementary maffs and engineering, we can turn a 1970's Fiat into a street racer. A well known fact petrol nerds have been exploiting for generations to help them get lucky.
A little less known but equally true fact is that we can apply the same ″turbo charger″ concept to the combustion chamber of our water heater and we improve the energy efficiency of the unit. Which means we can heat more water instantaneously, and also we can use less gas doing it. So unlike the '70s Fiat which no matter what lipstick you slap on the pig, remains a skorokoro. Our improvements help achieve world peace.
Having electrical power available enables us to read the incoming water temperature, and control the flow rate of the water, so we provide constant temperate supply, we can perform self diagnosis, and we can run more efficiently.
The step up from the battery operated units to the ″fan assisted″ units is significant. If it's an option we almost always recomend a fan assisted unit. But there are two ″cons″ to ″cons″ider:
Cost, as always, is a subjective price benefit decision. The fan assisted model is almost always a better unit, if it's worth the price is not so definitive an answer.