September 15, 2008

Dear Readers:  To cover or not to cover:  That's the question I get asked this time of year by folks who have central air conditioning.   Should you shroud that outdoor condensing unit?   I like the idea, since it's so easy and inexpensive.   Admittedly, these units are coated with weatherproof enamel paint and have self draining holes to get rid of melting snow and rain.   But they will look prettier longer and probably last a few more years in service if they are protected form harsh winter conditions.  You can buy an inexpensive plastic cover, complete with a rubber strap for less than $15 at a big box store.  I use conventional bungee cords to secure my cover, as they create a more snug fit around the bottom.
If you have an odd size condensing unit or need to cover a swamp cooler or window air conditioner, check out www.coolercovers.com or accovers.com for custom sizes.
 
Carol wants more hot water:  I am on hard well water, and asked the Rinnai rep if an on-demand water heater would work.  He said no.  What do you think?  I don't have a lot of room for a regular tank.
The rep is probably worried about excessive mineral buildup inside the tankless water heater that would eventually reduce its efficiency, if not plug it up altogether.  One idea is to install a water softener in the pipe leading to the hot water side of the plumbing.   A traditional sodium/ion exchange softener would work, but you shouldn't run its brine discharge into the septic tank-run it outside instead.
I've explained before that in existing homes, these tankless models are too pricey for me.  By the time you increase the size of the gas line and maybe the flue pipe, too, you'll have around $3000 invested in the system.  That extra cost will take many years to amortize itself before you start saving actual money.  Considering that you can buy a half dozen regular water heaters for that kind of money, I would probably stick to a traditional model.
If space is an issue, remember that you could buy a small electric water heater that can go almost anywhere-even in an out-of-the way closet.   If you want to stick with a gas-fired model, there is now a direct vent version, whose flue pipe sticks through an outside wall;  that way, you're not limited to one central location near the chimney.
 
Cliff's radio is acting up:   There is a pretty bad hum/buzz when I listen to AM radio.  How can I get rid of it?
The interference usually originates in one or more of the fixtures in your house.
Its' pretty easy to isolate the source.  Simply turn off one circuit breaker at a time until the noise quits.  Then you can check out which of the  devices in that circuit is to blame.  The usual culprits are fluorescent lights with bad starters or flickering bulbs, night lights and porch fixtures with a photo cell sensor, touch-to-dim lamps, ceiling fan speed controls, or slide-type light dimmers, like many of us have in the dining room.  The photo cells are the worst, because at sundown each day, they flicker as the ambient light gets dimmer and they struggle to come on.  Replace them with motion detector fixtures, and you'll not only quiet down the interference, but you'll also save money.  If you can't resolve this yourself, call an electrician to check for loose wires in the main panel or inside plugs and switch boxes.
Other, more exotic causes of radio noise can be arcing or other faults in the overhead power lines, like dirty insulators;  or a nearby amateur radio station.   Virtually all of these "ham" radio operators want to be good neighbors, are very sensitive to this problem and will go out of their way to help you fix it.
 
Allan has pests:  I recently saw an infomercial about a device that sets up a "field" around the house to keep rodents away.  What do you think of these?
Not much.  The feedback from readers and listeners about these electronic deterrent devices is not good.  They usually rely on ultrasound or electromagnetic field technology, but it appears that, eventually, mice and other pests get used to them and come back into your life.  Traditional exterminating techniques seem to produce better results.