Friday, June 28, 2013

Distributed Whole House Audio

Music Anytime and Anywhere.
 
Tired of the iPod dock or radio sitting on the kitchen counter?  Imagine a pair of speakers recessed in the ceiling or in the wall.  The equipment is hidden in a cabinet, or maybe it's in the basement out of the way.  You're controlling it all with maybe a wall mounted control panel, a small keypad, or even your iPhone.  Distributed whole house audio can open up the possibilities for you.
 
Music Throughout the Home or Business
  • In-ceiling Speakers
  • In-wall Speakers
  • Bookshelf, Floor, Speakers
  • Volume Controls (Knobs, Keypads, Portable devices)
  • Access to iTunes, Pandora, Spotify, Internet Radio
  • Equipment Located in a Central Place
 
Our installations also include:
 
  • Advanced Audio Control Systems
  • Stereo Receivers
  • Speaker Selectors or Distribution Amplifiers
  • 14 Gauge High Quality Speaker Wire

Learn about the options available within your budget.
 
Stafford Home Service, located in St. Louis Park, MN, specializes in residential electrical, heating and cooling (HVAC), audio video, and security systems for clients in Minneapolis, St. Paul, and the Twin Cities Metro Area.
 
Contact us today for your free estimate.

Friday, October 19, 2012

How Does a Power Surge Affect Your Home?


When most people think of a power surge, and damage it may cause, they think of their computer and a long power strip to plug the computer into.  A computer is indeed one electrical device that a power surge may cause damage to in your home, however as today’s electronics overall become more sophisticated, a power surge can damage much more than just your computer.
Many appliances today run from an internal computer.  For example, newer laundry machines and HD TVs all run from an internal computer that if hit with a power surge will be rendered just as useless as your home desktop computer if it hit with one.
Installing a power strip protector on all of your high-end appliances in not convenient, or in most cases is it even possible.  A whole house surge protector will protect your expensive appliances and TVs. 
A surge protector is installed by a licensed electrical professional at the source of power for your home; the electrical box.  The job of the whole house surge protector is to even out the flow of electrical current to your home so your high-end appliances won’t become overloaded by too high of a spike in the flow of current. 
Power surges are cause by a variety of things that can include lightning strikes and downed power lines.  Summer electrical storms and winter snow pile up and times when your home can be especially vulnerable to a sudden surge in power. 
The whole house surge protector diverts large surges in power before they enter the home and cause damage.
For your best protection, Stafford Home Service recommends a whole house surge protectors at each of your electrical boxes in the home.  To ensure your computers and televisions are protected at the highest level, high quality power strip protectors are also recommended.
To learn more about surge protectors and how to protector you home, contact Stafford Home Service at www.staffordhomeservice.com, or call 952-927-7194.

Electrical Hazards and the Holidays

Making your home festive for the holiday season is a wonderful tradition.  Yet, with each strand of twinkle lights, you may be stringing up potential fire hazards.  To ensure your season is filled with good Christmas memories and not ones involving the fire department, be sure to follow these few tips regarding your holiday decorations.
The U.S. Fire Administration (http://www.usfa.fema.gov/citizens/focus/holiday.shtm) recommends the following precautions for the holiday season.
1.    Use non-flammable decorations.  Many of tree lights on the market today are cool lights meaning they stay cool to the touch.
2.    Check your Christmas tree lights before hanging them to ensure they are in good working order.  Look for and replace any broken bulbs.
3.    Do not string more than three light strands together.
4.    Check the light cords periodically to be sure they are not warm.  A warm cord signals a problem and you should shut them off and investigate why they are warm.
5.    Do not overload your electrical outlets.
6.    Be sure your holiday lights do not have kinks in them.
7.    Water your tree frequently.  Never allow it to go completely dry.  Dry Christmas trees are one of the top three leading causes of home fires during the holidays.  Visit the U.S. Fire Administration’s website for a video regarding how a dry vs a wet tree reacts to fire.

For all of your electrical questions, call Stafford Home Service at 952-927-7194, or visit our website at www.staffordhomeservice.com.

The Safe Way to Make the Holidays Sparkle

Adding Additional GFCI Outlets to Your Home

Beautiful displays of holiday lights are a sure why to make the season brighter for you and your neighbors, but hanging outdoor lights and running power to everything can be a daunting task especially if your outdoor outlets are scarce or not located in easily accessible spots.

Adding additional outdoor outlets can make the task of hanging outdoor lights less frustrating.

When considering additional outdoor outlets, it’s important to understand what a GFCI is and why you will need it.

A GFCI, or ground fault circuit interrupter, is required in:  kitchens, bathrooms, garages, outdoor outlets, crawl spaces and unfinished basements.  You will also be required to have a GFCI in places where equipment draws large amounts of current, or if water is present in any way.
 
What does a GFCI do?  When there is a break in the low-resistance grounding path from a tool or electrical system the electrical current may take an alternative path to the ground thus creating a ground fault.  The electricity may take a path through a user or something a user may unknowingly touch which would result in a shock.  These shocks will cause serious injuries or death.  The ground-fault circuit interrupter, or GFCI, is a fast-acting circuit breaker designed to shut off electric power in the event of a ground-fault within as little as 1/40 of a second. It works by comparing the amount of current going to and returning from equipment along the circuit conductors. When the amount going differs from the amount returning by approximately 5 milliamperes, the GFCI interrupts the current and shuts off the flow of electricity.*

When considering an outlet for outdoor use, a GFCI is what you will need.  This type of ground fault interrupter may be built into an electrical system, or it may also be a cord-connected GFCI.  There are actually three types of GFCIs.  They are:
•    Receptacle Type- you’ve probably seen this type of receptacle in your bathroom.  They typically have a test and reset button incorporated into the device.
•    Portable Type- This is just what the name implies, a portable system that may be designed to plug into a receptacle.
•    Cord-Connected Type- The Cord-Connected Type of GFCI is an attachment plug incorporating the GFCI module. It protects the cord and any equipment attached to the cord. The attachment plug has a non-standard appearance with test and reset buttons.

Benefits of a GFCI include:
•    Prevention from accidental electrical shock
•    Prevention of electrical fires

When considering additional power sources this year to hang your holiday lights, remember to be safe and use a GFCI system.

For an estimate on adding this type of outlet to your home, contact Stafford Home Service at 952-927-7194.
*Source:  http://www.osha.gov/SLTC/etools/construction/electrical_incidents/gfci.html.

Generators

Being prepared for a power outage gives many peace of mind.  A home generator, if maintained and installed properly, can ensure you keep your lights on during an outage.
Here are some tips to help in your purchase decision as well as some helpful insights into the proper maintenance of a home generator.
Power capacity
There are many online calculators to help estimate required generator size. These assume many things and provide a reasonable guideline, but can also suggest a much larger generator than you really need. Ideally, make a list of items you will be using during an outage. Look at the label on each appliance to find its power requirement in watts or VA. Ideally you could measure the current requirement with a peak holding meter to determine maximum startup current and operating current. Startup current is important.
Many items with electric motors will have two current ratings. When they start the motor requires much higher current to begin turning than is needed after they have started to turn. A deep well pump could require over 25amps to start, but only about 6A once water is flowing. Similarly a fridge or freezer could require 15A for a very brief moment while the compressor starts but settle down to a few amps afterwards. Items such as a microwave oven or a toaster oven will usually create a steady current flow without significant peaks at startup.  If you can juggle electricity use the size of the generator can be reduced.
Generators usually have two power ratings. The lower of the numbers is usually a continuous or running power rating. When adding up all the power requirements above, this number will be the total of normal operating powers of the items being powered.
The higher number is usually labeled as surge or startup power. This is the higher of the ratings measured. It is unusual that several devices will require maximum startup current simultaneously, so consider the largest load only when determining this number.

Fuel source
Consider what might become scarce or difficult to get during an outage, especially if accompanied by bad weather. Most fuel stations will not be open if there is no electricity. A natural gas connection to fuel the generator may be ideal if available. Propane is a good option for longer run times if the home uses it already for cooking or heating. Gasoline will allow the generator to remain portable for camping or to loan to a neighbor. Gasoline generators do require stabilizer and cannot be stored more than a few months before being used. 
Engine type
Overhead valve engines typically run more efficiently and last longer than side valve engines.

Noise level
Portable generators can be noisy. If you have neighbors nearby or the noise is unbearable in your house here are some ideas.
•  Choose an operating location as far away as possible. Note that a larger gauge wire is needed to reduce voltage drop as line length increases. Reducing line loss is required to minimize power loss and to ensure maximum power is available to the house. Lights will flicker less when heavy loads are attached.
•  Change the exhaust system. Noise from the portable generator systems comes primarily from two sources, the engine block and the exhaust system. With an air cooled engine there is little you can do about block noise. Some engines can have a larger muffler attached or make other changes to the exhaust system. Merely mounting exhaust pipe vertically will noticeably reduce noise.
•  Build a noise shielding enclosure. This could be as simple as a piece of plywood to reflect sound away from the house to a separate shed to hold the generator. Design your enclosure with safety in mind. Provide adequate air circulation and ventilation to prevent heat buildup and to remove carbon monoxide.
•  Small muffler will not reduce noise level significantly. Some come with a low tone muffler which helps, but the noise level is still very high. Honda and some Chinese clones make very low noise generators in power levels up to about 3000 watts. There are techniques to help reduce the noise level.

Placement
•    During a snowstorm you will not want to trudge to an inaccessible shed to retrieve your generator.  Find a place within you home where the generator is easily accessible.

•    Keep the generator in a dry area.  You will not want it getting wet during use.

•    Avoid flammable materials with your generator.

•    Place it away from paper, brush or trees.  Generator mufflers get very hot and could cause a fire it place too close to these items.

•    Make sure the exhaust gases of the generator are not blocked.

Maintenance
•    Test the generator every 1-2 months to ensure it is working properly.  The last thing you want is a broken generator when you really need it.
•    Be sure to use a fuel stabilizer.
•    Apply a small load to the generator when testing it to maintain the health of the magnetic field.
•    Keep it clean!  This is very important to ensuring your generator will work when you want it.
    Clean oil
    Clean air
    Clean fuel

Thursday, October 4, 2012

Heat Recovery Ventilator(HRV)/Energy Recovery Ventilation (ERV)

Energy recovery ventilation systems provide a controlled way of ventilating a home while minimizing energy loss.  Heat recovery ventilator (HRV) can help make mechanical ventilation more cost effective by reclaiming energy from exhaust airflows. They reduce the costs of heating ventilated air in the winter by transferring heat from the warm inside air being exhausted to the fresh (but cold) supply air. In the summer, the inside air cools the warmer supply air to reduce ventilation cooling costs.

Types of Systems
There are two types of energy-recovery systems: heat-recovery ventilators (HRV) and energy-recovery (or enthalpy-recovery) ventilators (ERV). Both types include a heat exchanger, one or more fans to push air through the machine, and some controls. There are some small wall- or window-mounted models, but the majority are central, whole-house ventilation systems with their own duct system or shared ductwork.

The main difference between a heat-recovery and an energy-recovery ventilator is the way the heat exchanger works. With an energy-recovery ventilator, the heat exchanger transfers a certain amount of water vapor along with heat energy, while a heat-recovery ventilator only transfers heat.

Because an energy-recovery ventilator transfers some of the moisture from the exhaust air to the usually less humid incoming winter air, the humidity of the house air stays more constant. This also keeps the heat exchanger core warmer, minimizing problems with freezing.

Most energy recovery ventilation systems can recover about 70%–80% of the energy in the exiting air and deliver that energy to the incoming air. However, they are most cost effective in climates with extreme winters or summers (like Minnesota), and where fuel costs are high.

Installation and Maintenance
Energy recovery ventilation systems usually cost more to install than other ventilation systems. In general, simplicity is the key to a cost-effective installation. To save on installation costs, many systems share existing ductwork. Complex systems are not only more expensive to install, but they are generally more maintenance intensive and often consume more electric power. For most houses, attempting to recover all of the energy in the exhaust air will probably not be worth the additional cost.

In general, you want to have a supply and return duct for each bedroom and for each common living area. Duct runs should be as short and straight as possible. The correct size duct is necessary to minimize pressure drops in the system and thus improve performance. Insulate ducts located in unheated spaces, and seal all joints with duct mastic (never use ordinary duct tape on ducts.)

Also, energy recovery ventilation systems operated in cold climates must have devices to help prevent freezing and frost formation.

Energy recovery ventilation systems require more maintenance than other ventilation systems. They need to be cleaned regularly to prevent deterioration of ventilation rates and heat recovery, and to prevent mold and bacteria on heat exchanger surfaces.

Benefits ERVs provide:
By transfering energy from exhaust air to incoming air, less energy has to be put into conditioningthe supply air, reducing consumption.

 Because indoor air quality is generally lower than it is outdoors, ventilation is sometimes vital. This equipment help improve those conditions.