Linux smart homes for dummies - part 8 pdf

Waking Up to a Warm House

X10 thermostat systems can operate in the same way as programmable ther￾mostats by using an X10 timer, or you can let your computer do the timing.

For more information on automating your X10 modules with your computer,

see Chapter 16. The X10 Mini Timer (which looks like a small alarm clock and

can function as an alarm clock with a snooze control) sells for about $30 and

can time four groups of X10 devices twice a day.

You can program either your computer, running MisterHouse, or your X10

Mini Timer to control your thermostat system in the following ways:

If you’re using a two-thermostat X10 control system, as I describe pre￾viously, with one thermostat connected to a Universal Module, you can

send an On signal to your Universal Module set attached to the thermo￾stat with your comfort temperature and start heating up your home half

an hour before you need to wake up. And you can send an Off signal half

an hour after your expected bedtime, which gives you time to warm up

your sheets with your body heat before your room cools down.

If you’re using a Thermostat Set-back Controller (described in the pre￾ceding section), about half an hour before you need to wake up, you can

send an Off signal to it to stop fooling the thermostat into thinking the

temperature is warmer than it really is and start heating the house. Then

you can send an On signal about a half an hour after your bedtime.

If you are using a TXB16 X10-controlling thermostat, you can send the

X10 code to reset the temperature for the actual degree that you want it

to be before you wake up, and you can send a different X10 code for a

lower actual temperature after your bedtime.

Saving Money with Controlled Heating

Energy companies say that setting your thermostat back 4 degrees can save

$35 to $50 per month in energy bills. So, if you set it back 10 degrees while you

aren’t at home all day or asleep at home, you can probably save lots of money.

With energy prices soaring, micromanaging the heat is a good way to go.

If you have a Universal remote, or even better, a keychain remote, or best of

all, a computer that knows your schedule — such as when you plan to be at

home and when you need to work or go on a trip — then you can control

your furnace or air conditioning by pressing a couple buttons as you leave

the house, or you can program your schedule into your computer. And for

coming home, unless you have computerized your schedule, you can use a

touch-tone controller and send an X10 signal by using the phone to get your

home warm again for when you walk in the door.

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Some other considerations exist for the X10 thermostats, as well. For

instance, if you are going out for a really short time, does it save you money

to raise and lower the temperature? If so, how much?

Another way to save money is by zoning your heat. The Linux DIY Zoning

Project offers a huge amount of information regarding saving money. This

project lives at http://diy-zoning.sourceforge.net.

Saving money by using X10

thermostat systems

It used to be thought that the best way to save money with controlled heating

was to set your thermostat at a single temperature, as low as you can stand,

and to leave it there throughout the day, unless you are going on vacation.

The thinking was that because it takes more energy to increase the tempera￾ture of a home than it does to keep it at a constant temperature, it is best not

to change the temperature of the home much. Some HVAC contractors, even

today, say that it is not a good idea to adjust your thermostat too many times

during the day.

But recent research shows that the extra energy to bring a home up to a cer￾tain temperature is exactly equal to the amount of energy saved while the

home is cooling off. This means that all the energy saved with your home

at a constant lower temperature is money in the bank.

However, if you live in a home with lots of thermal mass, such as brick, stucco,

logs, earthen walls, concrete, and more, the time that it takes for your home to

cool down and heat up might be quite a bit longer than a home without a lot

of thermal mass. This means that if your home doesn’t cool down quickly, you

can’t save money by lowering the temperature for shorter intervals than it

takes your home to cool down because an equal amount of extra energy is

needed to raise the temperature back to where it originally was.

You might want to monitor how long it takes your home to cool so that you

know when to make the effort to turn down your heat and when it just doesn’t

matter.

Saving money with the Linux

DIY Zoning Project

Zoning your home gives you the ability to maintain the heating or cooling of

different areas of your home at different temperatures of your choice or at

the same uniform temperature. You achieve zoning zen by dividing the home

into functional heating zones, placing temperature sensors in each of the

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zones, and then controlling the heat by using electronic duct dampers, which

can open or close remotely, as shown in Figure 12-3. Zones can be groups of

rooms or individual rooms. You can create any number of zones in your

home.

Before embarking on DIY Zoning, be sure you understand thoroughly all the

information that the DIY Zoning Project provides. Zoning your home this way

needs to be considered as a labor of love and not a chore. If you’re into it, by

all means give it a try. Just don’t bite off more than you can chew. Find an

HVAC professional to guide you through it. Hire him or her for the tough jobs,

and let him or her tell you what you can do and shouldn’t attempt.

Saving money with zoning

Zoning your home allows you to save money in the following ways:

Maintain a proper temperature balance in your home, regardless of

the time of day and the amount of sunlight heating up the outer walls of

your home. This saves money by not wasting heat when you need to

increase the heat in rooms that don’t need it.

Zone your heat so that the areas of your home that you occupy at cer￾tain times are warmer than areas that you do not occupy. This saves

money because your furnace needs to work less hard than if it were

heating the entire house. For instance, you can supply more heat to the

bedrooms at night and less to the living room, kitchen, utility room, and

other areas that you don’t occupy during those times. Or during the day,

you can supply more heat to the living room and less to the bedrooms.

Install and use a furnace and air conditioning unit that is less power￾ful than one needed in an unzoned home because the demands on

them are less. You save money because a smaller furnace and central

air conditioner costs less and also takes less energy to run.

Heating

or

A/C

Zone 2

Zone 1 Zone 3

Electronic

dampers

Electronic

damper

Figure 12-3:

Zoned

heating

and air

conditioning

systems use

electronic

dampers to

control the

heat in the

different

zones of the

home.

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