Archive for April, 2010

life: extending the life of a household water heater

My home has a gas-powered hot water heater located in the walk-up attic (3rd floor). I’d like to give the architect a dope-slap for doing that. Especially when the master bath directly below the water heater takes the longest to receive the hot water. But the real reason why the attic location is an issue is because there have been two incidents where the water heater has leaked which ended up sending water spilling down the lower two floors. If only they could have put it in the garage. Sigh.

Anyway, one of the leaking incidents occurred recently. I just woke up the kids for school. I’m standing in their bedroom on the 2nd floor and asking myself, “why do I hear water running above me?” So I grab a flashlight and dash upstairs to the attic. There is water flowing out of the top of the water heater and down the sides, as if it has ruptured. At least the water heater is surrounded by a drip pan which drains outside the house. The drip pan was full to the brim, and just a little bit had spilled out. I quickly shut off the inlet valve on the water heater and the pan continued to drain. It looked like less than half a gallon had spilled outside of the pan, I consider myself very lucky. Time to call for a replacement water heater. I also take note to make sure the drain on the outside of the house for the drip pan is free of debris that may interfere with draining.

Since the water heater is in an attic closet bounded by the A-frame roof, there is limited height. It turns out that my water heater is a few inches shorter than the typical short model, so it is a bit of a specialty product that the typical big-box retailers don’t carry. So I need to call a real plumber. Although the plumber did a first-class job and was done within 4 hours of when I called them, it also cost me $1100. Ouch.

So while the plumber was working, I was my usual inquisitive self and was asking questions. And I had done some research on the net before calling the plumber. The typical lifespan of a water heater is about 8 years. Mine had died at about the 9 year mark, so it wasn’t out of bounds. The most common cause of water heater death is a build-up of sediment at the bottom of the tank. This sediment is present in the water supply, and simply settles while in the heater. There is a relatively easy way to flush out the sediment, which until then I had never heard of. Here is what the plumber told me:

The water heater should have on it what looks like a spigot near the bottom where you can attach a garden hose, just like the hose bib on the outside of your house you use to wash your car and water your garden. And once a year, you should do just that – a power flush. Get a garden hose (make sure it doesn’t leak before you do this), connect it to the spigot on the water heater, run the hose to a safe location (ie, a bath tub or out a window to outside), open the spigot on the heater and let the water blast though the hose for about 5 minutes. The water will be hot, so be careful that the hose and water output doesn’t hurt anyone or anything. Do not shutoff the inlet of the water heater, you want the water to blast out of the garden hose at pressure instead of simply (partially) draining the tank without pressure. The reason you want it to be pressurized is because of what is behind the spigot – a tube that causes the water flow to stir up the sediment on the bottom of the tank so it can be flushed out the spigot. When the 5 minutes are up, close the spigot (make sure it is fully closed), and remove the garden hose. Be careful of hot water that may still be in the garden hose while you are removing it.

You should do this once a year. I got a Sharpie pen and wrote on my new water heater “flush on March 15”. Had I known about this earlier, I would have done it and would expect a longer lifetime of my water heater. The plumber said that it should be possible to get several more years than average from a water heater that is well-maintained.

life tips marcelk 20 Apr 2010 3 Comments

tech: how to tell if your computer is 64-bit capable (for Linux fans)

For my x86 machines at work, I’m all Linux. Frankly, I just don’t understand Windows Server. Yes, my laptop runs Windows because I have business apps that need Windows. But all the real work gets done by Linux or its Unix friends or mainframes. (I’m sure there are people who will disagree, but I digress). So when I got some surplus hardware that was a bit old, I wanted to put a 64-bit Linux OS on it, but wasn’t sure if the CPU was 64-bit capable. So how to tell? Some search results focused mostly on running Windows and looking at the Computer properties, but I’m not running Windows. Thankfully, there is an easy way. (Some people complain Unix is user-hostile. I think it is expert-friendly. But I digress again).

Get yourself a Live CD of your favorite distro. My current favorite is Fedora. A Live CD is a bootable CD that will let you run the OS without installing it on your hard drive. Yeah, when you shut down all the data is gone, and the Live CD does run slow, but it is a great tool for doing tasks like the following. Most Live CDs are 32-bit, but that is OK – you need the OS just to probe the hardware.

Get to a shell prompt and run the command “cat /proc/cpuinfo”. The proc filesystem is something I have come to love as I’ve learned more about Linux, but I digress yet again. The output of that command should look something like this:

[marcelk@alma ~]$ cat /proc/cpuinfo
processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 15
model name      : Intel(R) Core(TM)2 Duo CPU     E6750  @ 2.66GHz
stepping        : 11
cpu MHz         : 2000.000
cache size      : 4096 KB
physical id     : 0
siblings        : 2
core id         : 0
cpu cores       : 2
fpu             : yes
fpu_exception   : yes
cpuid level     : 10
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi 
mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx smx est tm2 cx16 xtpr lahf_lm
bogomips        : 5323.55
clflush size    : 64
cache_alignment : 64
address sizes   : 36 bits physical, 48 bits virtual
power management:

So out of all those lines, take a look at the one that says “flags:”. There are a bunch of codes there, the meaning for those codes is described in the file /usr/include/asm/cpufeature.h. The flag you want to see is “lm”. It’s an abbreviation for “long mode”, which basically means your CPU is x86_64 capable. So you can run 64-bit Linux, 64-bit Windows, or 64-bit whatever, even though you currently aren’t running it at the moment. If the “lm” flag doesn’t appear, then you have only a 32-bit CPU that can run only a 32-bit OS.

So yes, I can run 64-bit Linux on the computer above. And so… squirrel! … but I digress again.

tech tips marcelk 17 Apr 2010 2 Comments

local: pollen

pollen picture This is one of those local things that you neither would have heard about nor believed until you see it. For a couple weeks in the spring in North Carolina, the pine trees dump a huge amount of pollen. I’m not talking about a little bit of pollen that a bee would gather, I’m talking about coat-the-world, make-the-atmosphere-dusty, clog-your-nose kind of pollen. The interior of my car is coated with a yellow dust. Every flat surface in the house has yellow dust. I have pollen tire tracks in my garage. When it rains, it looks like yellow paint was dumped in the gutters. It really is unbelievable.

For a quick photographic description, here is a picture of the stairs going into my office building. That yellow stuff is pollen. It’s kind of clear where people have been walking. The rest is not dust, not dirt. That is pollen. It comes from the long leaf pine. The prolific pollen is probably what permits this pine to grow like weeds around here. The good news is that it lasts a couple weeks and a good couple rains washes it away. But the really good news is that this pine pollen is too large to be absorbed into the bloodstream, so it doesn’t effect people.

Uncategorized marcelk 07 Apr 2010 No Comments