One of our more recent projects involved swapping out a tankless water heater that was being used for in-floor heating but simply kept failing. The reason is that, although tankless water heaters can be great for delivering domestic hot water, they simply were not designed to be great sources of radiant heat. When it comes to heating your home with water, there’s a reason why boilers have been doing the job for decades.
The Tortoise and the Hare – we all know how the story ends
Let’s use a quick analogy to hammer home the point. Say you had to haul timber up a steep hill and you were given two vehicle choices to accomplish the task, a Ford Mustang and semi truck. Now, we all know that the Ford Mustang is a fine car and would blow the doors off of a semi truck in a straight line but hauling timber with it is probably not the best idea. Tankless water heaters were designed to heat up cold water from the water main quickly and in relatively short cycles, and it does this well. In contrast, boilers were designed to continuously heat water over long cycles and a slightly lower temperature to be circulated throughout the house to generate radiant heat. The implication of this contrast? Using a tankless water heater for radiant heating means putting undue stress on its heat exchanger thus drastically lowering its operating lifespan.
The best of both worlds – the combi boiler
For the reasons stated above, this is why we see multiple failures with tankless systems being used as in-floor radiant heating systems. They were not designed to do this very well and in most cases that we’ve encountered, nor were they installed properly. A particular local area of concern is the neighbourhood of Harbour Landing in Regina. We’ve already seen many of these tankless water heater systems there that we’ve had to repair. The problem is that eventually they will all most likely require replacement as in-floor heating systems. As a solution, we’ve been replacing non-functioning units with Navien combi boiler systems. These tankless systems are the perfect solution for both domestic hot water needs and radiant in-floor heating.
Want to learn more about combi boiler systems? Contact us today.