Replacing a Furnace Blower Motor Control Board

It has gotten cold early this year, and I found myself firing up our furnace before the summer was officially over. I was thrilled to find that there was no hot air coming out of the vents.

Diagnosing a Bad Blower Motor or Blower Motor Control Board
I quickly realized that the blower motor was not coming on. For those not familiar with the different parts of a furnace, the blower motor is what forces the hot or cold air through the duct work and out of your vents.

The normal heating sequence of a gas furnace starting up goes something like this:

1. Thermostat calls for heat (24 volts AC is applied from the R terminal to the W terminal inside the thermostat)
2. Furnace inducer fan starts. The inducer fan creates a draft through the furnace, closing a pressure switch.
3. After the pressure switch is closed for a preset amount of time, the pilot light is lit by an electronic ignitor unit (older furnaces do not have this, and have a standing pilot instead).
4. A bimetal strip located near the pilot light heats up and closes a switch.
5. After this switch is closed for a preset amount of time, the main gas valve is permitted to open and the burners fire up.
6. After a preset amount of time, the blower motor will start and begin to blow the hot air through the ducts.

Step #6 was not happening for me, and the furnace would eventually shut down due to overheating.

In order to verify that the problem was not with the motor itself, I turned the FAN setting on the thermostat to "ON" from "AUTO". This tells the control board to turn on the fan regardless of whether heating or cooling is being called for by the thermostat. The blower motor started up when I did this, so I knew the problem was likely with the control board.

Locating the Control Board

The control board should be located near the blower motor, and is likely concealed by a steel electrical junction box with warning labels on it. If you're not sure where the blower motor is, it should be right next to the air filter. If you don't know where the air filter is....well then you need to find it, and change your air filter! Notice in the image below that there is a spring load switch in the upper left hand side of this compartment. This switch cuts the power to this compartment when the cover is off for safety purposes.

Furnace Blower Motor Compartment

After taking off the cover of the steel electrical box, you should see the blower motor control board (see image below). 

 Control Power Transformer & Blower Motor Control Board

The large objects in the middle are relays, which send power to the blower motor when the command to turn on the motor is received. These are old style relays, and they have a translucent cover on them that allows you to actually see a spark when they open and close the circuit. The relay on the left is for the "LOW" blower motor speed, used for the heating mode. The relay on the right is for the "HIGH" blower motor speed, used for the cooling mode, as well as for when the switch on the thermostat is set to "ON".

The relay on the left was not sending power to the fan when it received the command to do so. After removing the relay, it was no mystery why. See below.

Burned up relay

It should be noted that these particular relays are not intended to be easily replaceable; I actually pried this relay out of its solder joints. Also, it's not cost effective or logical to try to replace this antiquated relay. Depending on the type of control board the furnace uses, there is likely an updated version of the board that can be purchased for a reasonable price.

Removing the Control Board

The board was held on with (2) 1/4" hex screws near the bottom. In fact, it seems like every fastener on my furnace is 1/4" hex. I'm guessing this is the industry standard. I made sure to take note of where the existing wires were terminated.

Thermostat, humidifier, and A/C control wire terminations

There is also a plug connector where the board sends and receives control signals to the other components. This pries out easily.

Plug connector pries out

Plug connector removed

Installing a Replacement Control Board

I was able to find a brand new replacement board made by ICM on eBay for $45. The replacement board has some additional features, a fuse for protection against short circuits, and modern electronic components.

Old board on the left, new on the right

Looking at the back of the circuit board, notice that there are circuit board traces going through one of the screw holes. It is important to make sure the board is screwed in at this point, as it is grounding the board to the furnace enclosure.

Control board grounding point

There are many wires that need to be terminated on the new board. The thicker wires will have spade connectors on them, which allow them to be easily plugged into the terminals on the board. The board will also have a few letters next to each connector to indicate what should be plugged in where. See below for the 120V connections on the new board.

New control board 120V connections

Here's a summary of what the identifiers on the board mean:

LO: This is the red wire that goes to the blower motor. This terminal is energized when the low speed of the blower motor is called for by the heating cycle.

HI: This is the black wire that goes to the blower motor. This terminal is energized when the high speed of the blower motor is called for by the cooling cycle, or by the fan "ON" switch on the thermostat.

PR1: This stands for primary #1, referring to the primary side of the control power transformer. The black wire from the transformer gets terminated here.

L1: This stands for line #1, and gets connected to the incoming hot wire of the 120V circuit, which is the black wire

PR2: Primary #2. The white wire from the transformer gets terminated here.

L2: Line #2. The neutral wire (white) of the incoming 120V gets terminated here.

COM: Common. The white wire from the blower motor gets terminated here.

SEC1 & SEC2 (not pictured): Secondary #1 & #2. This is the 24V which power the control circuits. The red and blue wires, respectively, get terminated here.

The thermostat wires also need to be terminated to the new board. Here's the industry standard color code:

White -----> W    Heat
Yellow -----> Y   A/C
Green ------> G  Fan
Black -----> C   Common
Red -----> R  +24V

Go here for a much more in depth discussion of standard colors and terminal designations.

End Result
Success! The new control board works as expected, and we saved a few hundred dollars by not calling out a tech.

DISCLAIMER: I am not a certified HVAC technician. This information is not representative of all furnaces, nor is there any guarantee of the accuracy of this information. Wire colors, while usually following the industry standards, can be different. If you are not comfortable with basic wiring concepts or the basic operation of a furnace, call a certified HVAC technician. ALWAYS turn off the furnace power circuit before working on it.

Landscape Lighting

My wife and I finally started giving our backyard more attention this year (OK fine, mostly my wife), and naturally I needed to find an excuse to throw some wires in the ground. Adding some simple landscape lighting was the perfect project.

Material List

Lights
I purchased a couple of 12V MR16 spot lights on Amazon for a very reasonable $11.99 each.

Paradise GL22724BK

Lamps (bulbs)
The lights come with 20W MR16 halogen lamps, however I wanted to use LED lamps instead in order to reduce the total wattage, as well as get a longer lamp life. I ended up purchasing these for about $7 shipped. They are most likely low end Chinese garbage, and will not last the 50,000 hours the high quality LED lamps are rated for, but for this application I wasn't looking to spend a lot on the lamps.

4W LED MR16

Note the increased depth when compared to a regular 20W MR16

Power Supply
Most landscape lights are low voltage (12V), so a power supply/transformer is needed. Since I was using low wattage LED lamps, I was able to save some money and purchase a low wattage power supply (30W). $17.99 on Amazon.

Intocircuit 30W 12V LED Power Supply

Wire
The best price I could find on the wiring itself was Menards for $26.49 for 100' of 16-2 (16 is the wire gauge, and 2 is the number of wires). 16 gauge wire is typically adequate for most normal circuit lengths and low wattage circuits.

16-2 Wire

Insteon Controlled Receptacle
Since I have an existing home automation system, I decided to control the landscape lights with an Insteon controlled receptacle. This is by no means the only way to turn landscape lighting on and off; many power supplies have a built-in timer, or a photocell could be used.

Insteon Receptacle

Installation Procedure

Determine the Light Locations
This may seem obvious, but it's a good idea to figure out exactly where the lights will go before thinking about the wiring. I put them about 2' from the trees I was planning on lighting.

Dog shown for scale

Determine the Wire Routing
It's helpful to predetermine the route the wiring will take, where the power supply will be mounted, and where the power supply will connect to line voltage (120V). We have a detached garage right next to the area where the lights were going, so that was a convenient location to mount the power supply and plug it in.

Install the Wiring and Lights
I forgot to take some pictures while burying the cable, but there's no mystery here; just dig a few inches down, push down the cable, throw the dirt back on top, and repeat. The lights come with a stake on the end, so they were very easy to push into the soil. I installed a "service loop" at each light, which is just a fancy way of saying I left excess cable in case I ever wanted to move the light in the future. The lights include splice connectors for making the final connections to the lights. The splice connectors are very easy to use, as they don't even require you to cut the wire to make the connection.

Typical landscape lighting splice connector

Install the Power Supply
Many landscape lighting installations have the power supply outdoors, since it is typically convenient to find a power receptacle mounted on the house or garage. I mounted the power supply inside our garage since it was so easy to route the wiring into the garage.

Power supply mounted to a stud in the garage

Install the Lighting Control Device
In my case, the lighting control device is the controlled receptacle. I wrote a program in the ISY-994i to turn this receptacle on at dusk, and off when we go to sleep.

Program to turn on landscape lights and front porch light at dusk

Program which performs multiple actions when I press a button on my phone

Updated MobiLinc interface with controlled receptacle for landscape lights

Final Product
For the cost and ease of the installation, I'm happy with the how it turned out. I'm not exactly being environmentally friendly by adding some upward light pollution for a few hours a night, but I'm over it. The photos make it look brighter than it actually is.

Starting a Home Automation System with the Universal Devices ISY-994i Automation Controller

 For a while now I've wanted to implement a home automation system into our home. I have some previous experience from setting up a system at my parents' vacation home, and I get a lot of enjoyment out of the whole process. Here is the process I went through from selecting what products to use to getting the system fully functional. I'm not going to get too deep into the actual setup steps, as this is well documented at UDI's wiki page.

Selecting a Communication Protocol

The first decision I had to make was what technology to utilize. There are a few different technologies to choose from which send communication signals over power wires, wireless, or both:

X-10: Powerline communication, very old technology that is not always reliable. The only good thing about X-10 is that the products are the least expensive.
Insteon: Dual-band communication (powerline & wireless). There are many available products, and Insteon has a large user base. Insteon controllers can also communicate with X-10 devices.
UPB: A more reliable powerline communication protocol.
Z-wave: Wireless communication standard starting to be utilized more and more in DIY system as well as professionally installed systems, such as the ADT Pulse. The popular Mi Casa Verde VeraLite controller utilizes Z-wave.
ZigBee: Another wireless communication standard that has gained traction in the market, though there are fewer home automation products availabe.

Because of the large variety of devices available for Insteon, I decided to start my system with a few Insteon devices. The heart of any Insteon system is the PLM (PowerLinc Modem). This piece of hardware takes commands from an outside source and communicates them to the devices in the network. It also reports the status of all of the network devices.

Choosing How to Communicate with Devices

When deciding how I wanted to communicate with the PLM, I again had some options:

PC Software: This approach would require software such as HouseLinc, HomeSeer, or CQC. HouseLinc is free, while HomeSeer and CQC are more advanced and are somewhat pricey. This approach also requires a computer to be running 24/7 if you want to run time based events.

Dedicated Automation Controller: This approach requires the purchase of an automation controller. The advantage here is that you don't have to have a PC running 24/7 in order to run events. Automation controllers are typically compact, light, and consume very little power.

I decided on the latter approach, mostly because I found the ISY-994i from Universal Devices. This controller has a great track record, great support via their forums, and a large user base. It is also relatively easy to create simple programs. The best deal I found was at Orchestrated Home, who is an authorized retailer for Universal Devices products. I purchased the kit that comes with both the controller and the Insteon PLM.

Setting up the Hardware

Below are some shots of the package contents of my shipment from Orchestrated Home. The ISY-994i comes with a power supply, instructions, and two Cat 5e cables (one for connecting to the LAN, one for connecting to the PLM.) The unit itself is much smaller and lighter than I expected. The PLM includes a 8P8C to female DE9 serial cable, in case you wanted to connect it to a device that has a more traditional male DE9 connctor for RS-232 serial communication, like a PC. This cable is not used in my setup.

Contents of the ISY-994i and INSTEON 2413S PLM boxes

 

Front Panel of the ISY-994i

 

Rear Panel of the ISY-994i

ISY-994i and PLM installed in my data closet

For the actual Insteon devices, I purchased the Insteon Comfort Kit, which contains an Insteon Hub (which I promptly put on eBay since the ISY takes its place), an Insteon thermostat, and two dimmable lamp modules. Purchasing these items as a kit provided signficant cost savings over purchasing these items individually.

In order to install the the thermostat, I had to update my thermostat wiring since I had an old 4-wire setup, as I showed in this post. I hooked up the LampLinc modules with both of the LED replacement bulbs I recently purchased, which I reviewed here.

Insteon Comfort Kit

Insteon Thermostat



The thermostat has a bright blue backlight

Insteon LampLinc Dimmer

Setting Up the Software

Once you're able to determine the ISY's IP address, the setup is pretty simple. I was able to start writing programs almost immediately. The whole startup process was very painless, and I was up and running in less than an hour.

The programming architecture uses an If/Then/Else format. A "Condition" is added to the If field to be tested; if this test is True, then the program will run the code in the Then field, and if it is false, it will run the code in the Else field. The concept is simple, but it takes time of writing different programs, testing, and troubleshooting in order to really get the hand of it.

The ISY's programming is a little bit different than what I am used to. The programs themselves have a True/False state. If the Then fields were run last, then the program is true. If the Else fields were run last, then the program is false. Because of this, programs can (and should) be used as boolean variables.

Below is an example of one of my programs. This particular program will turn on the living room light in the morning at the times and days specified in the If field as long as the light isn't already on. It also starts at a dimmed level, and then goes up to full output 30 minutes later.

If
(
On Mon, Tue, Wed, Thu, Fri
Time is 5:30:00AM
Or On Sat, Sun
Time is 7:00:00AM
)
And Status 'Living Room Lamp' is Off

Then
Set 'Living Room Lamp' 50%
Wait 30 minutes
Set 'Living Room Lamp' 100%

Else
- No Actions - (To add one, press 'Action')




The main page of the ISY's Admin Console



The Programs tab of the Admin Console



Configuration tab of the Admin Console

 Controlling the System Remotely

What good is a home automation system if you can't see what's going on at home when you aren't there? Any decent HA system has companion apps for Android and Apple devices that allow the user to perform any task they want. For my setup, I'm using MobiLinc, which seems to be the most popular app for interfacing with the ISY controllers. Unfortunately it's not free, but $19.99 seems like a fair price.

Setting up remote access to the system has a few hoops than you'll need jump through in order to get it working properly, such as port forwarding and setting up a dynamic DNS service. Those two topics are well documented, so I'll just leave it at that. I use dyndns.org for my dynamic DNS service, and it works great. Note that the ISY uses a secure port (default 443).



MobiLinc Main Screen

 

MobiLinc Lights Screen

MobiLinc Thermostat Screen



Summary

 

So far I've been extremely pleased with how well the system is working. Here's what I've been able to do so far:

 

-Outdoor lights automatically turn on at sunset and sunrise

-Turn on lights first thing in the morning

-Turn off lights when we go to work

-Have lights turn on by the time we get home from work

-Dim down lights at a certain time to encourage us to go to bed

-Create thermostat programs from the ISY (no more programming the thermostat from its tiny screen)

-Adjust the thermostat remotely if I forget to turn it up or down before leaving the house, or if I want to make the house a comfortable temperature by the time we get home.

-Create widgets on my phone to control lights and temperature without actually opening the MobiLinc app

 

In the near future I plan to add Insteon dimmers into the system in order to create lighting scenes (Dinner, Movie Time, Cleaning, etc.)

 

I would highly recommend going the ISY-994i route if you are considering your own home automation system. The team at Universal Devices has also come out with a Z-wave dongle which plugs directly into the ISY's expansion port, and adds the ability to control Z-wave devices. As of January 2014, this is still in the beta testing phase, however it looks very promising.



















 



Creating a Data Closet

Over time I've accumulated a lot of different pieces of equipment to run the various systems in my home. It didn't take me long to realize that I needed a dedicated space to place and organize all of this stuff. Here's a list of all my equipment:

HTPC (Home Theater PC)
Next Generation Remote Control Extender
Silicondust HDHomeRun Prime network tuner
Ceton Echo Windows Media Center Extender
Sewell 1x4 HDMI splitter
Motorola tuning adapter
Zoom 5341J DOCSIS 3.0 cable modem
12-port Cat 6 patch panel
Asus 8-port gigabit switch
Asus 5-port gigabit switch
PCT 4-port cable/internet signal amplifier
Various coax splitters
ISY994i home automation controller
Power Strip

One way to deal with all of this equipment is to purchase an equipment rack. I briefly considered going this route until I added up the cost of purchasing a rack and the necessary accessories. Another option is to install a structured wiring panel. These are great for keeping everything neat and organized, but this type of installation seems to have a lot of unnecessary costs like special shelves and power receptacles that will fit in the panel.

In the end, I decided most cost effective and functional installation for me was to just fasten some OSB (Oriented Strand Board, a cheap alternative to plywood) to the wall in an underutilized storage room underneath the stairs. This worked out great because the storage room is in a central location in my house.

Various Equipment Mounted to OSB

IR Extender and HTPC mounted off the floor in case of basement flooding

I'll admit it isn't pretty, but it has worked very well for me. It's extremely simple to swap out equipment, and there's plenty of room to work. Also, there's no special equipment needed to mount the components. Many components come with holes in the back for attaching to screws fastened in the wall. For components that don't have holes in the back, I just use zip ties with screw holes.

All of the wiring serving the coax and Cat 6 jacks in my house run back to this central location. This gives me a lot of flexibility. For example, I'm able to locate my wireless router in a room on the first floor rather than in the basement in order to have a stronger wireless signal on the first floor. This may not always be feasible though; if you have a finished basement with drywall ceilings, running new wiring can be difficult and frustrating.

So, if you're looking for a way to organize all of your AV, cable, and networking equipment, here's the process:

1. Identify a Location - Ideally your data closet should be centrally located, but it doesn't have to be. Verify that it is feasible to route existing and new wiring to this location.

2. Relocate or extend any existing wiring - My coax line from the cable company was split in the basement ceiling, and then went off to my cable modem and TV locations on the first floor. You'll likely need to do something similar if your data closet is in a different location than where the coax enters the house. Also, ideally you want all of the cable and network jacks in the house to terminate in this closet.

3. Layout the components - Locate the components in a logical manor, and try to keep some separation between different systems. This isn't critical, but it will help keep things organized and will reduce the number of cables that have to cross over each other.

4. Power - You'll need a lot of receptacles to plug in your components. Consider running a dedicated circuit to the closet and installing a power strip with a lot of receptacles. The one you see in the photo above can be purchased from Harbor Freight for around $20.

5. Fasten the components to the wall and make all final connections

Updating Thermostat Wiring

When I started researching replacement thermostats that will interface with my home automation system, I noticed that most of these thermostats require 24 volts to operate in lieu of the battery operated model that is currently installed. The 24 volts is normally provided by the 120VAC to 24VAC furnace transformer.

The reason that this was a problem for me is that I only had 4 wires coming to my thermostat; a 5th wire is needed in order to provide 24VAC to the thermostat. There are workarounds to this problem, such as this "add-a-wire" adapter. However, my house is a ranch with a full basement, and I was confident that I could easily run new wiring.

While I could have purchased 18/5 (a cable with 5 #18 AWG wires), it made more sense to run additional wires for use in the future, since many modern high efficiency HVAC systems are two-stage. I ended up purchasing 18/8 wire, which is 64 cents/foot at Lowes as of January 2014. I only needed 45 feet, so this worked out to cost less than purchasing a a 4 to 5 wire adapter, and I don't have another electrical component in the system that could fail in the future.

18/8 thermostat wire

If you are running into this same situation, and have a basic understanding of your furnace and AC control wiring, I would recommend putting in 18/8 in order to future-proof your system. That being said, if you have no way to fish new wires to your thermostat locations, the add-a-wire adapter is probably your best bet.

Lighting - 60W Replacement LED Comparison

I have never been a big fan of the compact fluorescent (CFL) bulbs made for the residential market. They take time to warm up to their full output, they contain mercury, and even the ones that are "dimmable" don't dim very well. I decided it was time to finally test out the newest generation of LED bulbs. Up until recently, LED bulbs were prohibitively expensive for the average consumer. Most people are not willing to spend $30 on a light bulb, even if it will pay off in the long run.

I chose to compare the Philips 424382 11W 2700K LED and the Cree 9.5W 2700K LED as these are the two most reasonably priced products ($13-$15) on the market currently, and they are both dimmable.

Side by side comparison of the Philips 424382 11W 2700K LED and the Cree 9.5W 2700K LED 

Appearance: Physically these bulbs are almost identical in height, but as you can see the big difference is the actual shape. The Cree bulb more closely resembles the traditional A19 bulb, while the Philips has more of a tapered look.

Philips 424382 at Full Brightness

Cree 9.5W LED at Full Brightness

Light Distribution and Output: Both appear to truly be 60W replacements. The Philips bulb puts out slightly more light (830 lumens vs. 800 lumens), but not by much. See images below. Notice that the Philips has a less defined scallop of light at the top than the Cree.

Cree

Philips

Color Temperature: Both bulbs closely resemble a traditional incandescent light source at 2700K.

Turn on time: Both are nearly instant-on, though I have noticed that this also depends on what type of dimmer you pair with the bulb. A standard light switch turns these on almost instantly, while my Lutron Diva C.L, which is meant for use with LED sources, has a slight delay with any LED bulb I use it with.

Dimming: Both bulbs dim with a standard dimmer, but the Cree has a few glaring issues:

1. Noise:  There is an audible whine throughout the entire dimming range. Some people may not notice, but it drove me crazy. The reviews of this product on Amazon confirm I'm not the only one that has noticed this issue.
2. Range:  The dimming range is subpar compared to the Philips. See the videos below.

The Philips bulb seems to dim to many different steps rather than continuously dimming. That being said, the Philips still outperforms the Cree in this category because of its quiet operation and it's excellent dimming range.

Fade to Off: If you have the Philips on a dimmer that fades to off, you'll notice that there is a slight flicker before the bulb turns off. The Cree does not have any flicker when fading on or off.

Phillips Dimming

Cree Dimming

Verdict:

The Philips is the winner for me. If your lights are on a dimmer, or if you can see the bulb, I would stay away from the Cree. The high pitched whining is a deal breaker, and the dark spot doesn't look great; however, some may like the dark spot as it does reduce glare at the top of bulb. The Philips bulb looks great and has superior dimming performance. 

The Cree is still a good product, and as of January 2014 can be found at Home Depot for $2 cheaper. I currently have it placed in a lamp where you can't see the bulb, and it's working just fine.