Sunday, January 31, 2010

Our government, protecting us

We've recently gone on an "energy efficiency" rampage at the house, replacing bulbs with CFLs, identifying devices that are unnecessarily left on all the time, wrestling with Windows to stay asleep during periods of inactivity, etc.  We also recently just installed a "continuous" or "on demand" hot water heater, replacing the 50G direct-vent tank heater we had (it was getting to the end of its lifetime and it was easier to replace it preemptively.) 

Unfortunately, the state requires all newly install water heaters to have a thermostatic mixing valve that limits the water temperature to 120 degrees.  (For tank systems, it is recommended to keep the tank water at 140, to prevent the bacteria that causes Legionnaire's disease, but 140 is hot enough to scald.  But continuous systems have a control system for the output temperature, so can be safely kept at whatever temperature you program in.)  And its probably not even working right, since the output temperature is even less than 120.  The valve adds cost to the system and to the installation (probably a dozen additional welds in addition to the valve), and while we now have an infinite supply of hot water, generated more efficiently, its not as hot as we like it. 

Reputable plumbers are not able to remove or bypass the valve, which means we need to either find a disreputable plumber or I need to do it myself (read: find an incompetent plumber.) 

Note to lawmakers: in my many years of successful shower use, I've learned a secret trick to avoid getting scalded: put your hand under the water first -- if its too hot, turn down the water temperature before getting in!

Thanks, elected officials, for making my house systems both more expensive and less useful. 


  1. I feel your pain, but those rules are likely not there to protect you (directly at least): Do you have kids? Do friends with little kids ever come to visit, and if so, are the young ones actively supervised at all times? Your simple trick may not occur to a 4 year old, though they have the ingenuity to turn on the shower even if the handle is out of immediate reach.

  2. Consumer protection regulations serve a valid purpose, but all such regulations must be subject to a cost-benefit analysis. Here, both the cost and benefit are suspect; the cost is nontrivial (I estimate it cost us several hundred dollars, AND has an ongoing nonmonetary cost in that the water is now not hot enough to our liking). (Plus these valves have a reputation for being a part that fails, requiring more expense to replace.) The benefit is also questionable; no amount of plumbing add-ons will keep a small child from burning his hand on the stove. Trying to create a world with the illusion that all is safe simply leaves people with less ability to cope with the risk that is inherent in the world.

    And yes, the kids here learned this trick at a young age too with no mishaps, and visiting kids are carefully supervised.

  3. It's an interesting question (well, to my goofy brain at least) -- I wonder how much research went into that temperature limit, when the calculation was made, and (if it was some years ago) how relevant the outcome remains today? If it was more than a few years ago, I doubt that energy efficiency was weighted nearly as heavily as it would be today.

    One could come up with regulations that allowed the safety valves to be further downstream, and selectively so. That could allow greater efficiency where it might be safer to do so, e.g. sinks. Scalded hands probably cost less than faces to those inclined to make that sort of grim calculation :-/