Going Tankless: Part II (for Real)

Remember when our water heater went out and we thought about getting a tankless water heater? Ah, the memories. It was in May 2006, but it seems like only yesterday that I was replacing that thermocouple. Wait, that's because it was yesterday! What do I mean? Well, the thermocouple went out again already.

Yes, I fear the 23-year-old water heater has reached the end of its useful life. I've replaced the thermocouple again, but how much longer can it go on? It's time to replace the entire water heater. Since the old beast is so layered with sediment that it won't even fill up our bathtub, this replacement isn't exactly a shock to us.

In fact, after it went out in 2006, I actually found someone on our beloved Craigslist selling a tankless water heater that had been installed in a mulit-family home for a few months. While the owner was glad at the energy savings, the residents weren't too happy when four people tried to shower at once.

If you aren't aware of the main performance difference between tankless and regular water heaters, the tankless design can't accommodate the same flow rate (gallons per minute) as a traditional heater. But as long as you get the right size, it isn't a problem. For exmaple, the unit I purchased is a Takagi TK2 which supports two major appliances. So although we never do laundry at the same time as showering, in theory, with this tankless heater, we could.

So while we limp along on our old standard heater, I contacted my good friend Jim, to help with the tankless installation since he has the exact same model. Also, there are some unique install considerations for these. Since tankless water heaters burn so efficiently, you can't use a standard exhaust duct... it has to be double-walled stainless steel. Jim also installs solar thermal water heaters, so he could help me install this so that if I ever wanted to go solar later on and use the tankless as a supplemental backup (a common configuration) there would be room to cut in the solar piping. Anyway, here's another photo of it during the installation process.


As you can see, the space-saving design is already a bonus as it tucks away into a 2'-wide space between the furnace and a foundation wall. I've already got plans for the area where our old water heater currently rots rests. Anyway, we're not quite done with the installation just yet, but we'll be wrapping things up very soon.