Carrier Infinity 96 cycle

[Joedella]

Hi, I'm Joe, a retired engineer. This is my first post.

We have an Carrier Infinity 96 furnace. When it cycles on, the blower runs at a nice, slow speed for about 5 minutes or so then it kicks into warp speed for about another 5 minutes. Why does it do * Can I change * The 2 guys that installed it a few years ago are long gone.

It only has a single stage t-stat. How much benefit will a two stage unit *

Sorry for all the questions, but inquiring minds need to know.

[Freon]

If you have the complete model number please post it.

Has the blower always run as you describe, slow then warp speeds, or is this a new event. What type of thermostat do you have. Look for any documentation that may tell you about programming the control board if that's where the blower speeds are derived from.

Your climate will tell you if a 2 stage system will help. Very cold climate you may see some savings but at the expense of a more complex system to maintain. I am a believer in the Keep It Simple Stupid school of design.

[Joedella]

Thanks for the reply, Freon. That's not r12 is -)

The unit has operated since it was installed in the summer of '09. When the installation was complete the AC was already running. I flipped the t-stat to "heat", jacked up the set pt. and verified that the unit did operate in the "heat" mode. I saw no need to continue heating a warm house, so I went back to "cool". I didn't find out about the warp speed fan until Oct or Nov, it has always done this.

The furnace is a Carrier Infinity 96 model #58MVB060-F built in 2009.

The t-stat is a Ritetemp #8029B wired as -
RC RH Furnace
W Furnace
Y Furnace
G Furnace

The only booklet I have is about the A coil installation.
The diagrams on the labels on the furnace front cover are of very little help here.

Thank you for your help.

Joe

[Freon]

I need the model number. Just post it as model 12345 without any other symbols.

Have you replaced the batteries in the thermostat.

Is there a C wire that you chose not to use with this thermostat. Powering the thermostat with the furnace 24 volts will make the batteries last much longer.

I think your issue involves the control board on the furnace and that's why I need the model number. The thermostat is a very basic one and will only call for the blower, not control its speed.

[Joedella]

The furnace is a 58MVB06 F 12114

C O and B are not used. I only have 4 wires between the tstat and furnace but that is easy to change. I did not chose to wire it this way that is the way it was installed.

Tstat batteries 2 AA alkaline were replaced about 3 months ago. Originals lasted about 3 years.

I agree that this a control board issue. With no instructions or detailed diagrams I can not proceed.

Sorry about my previous post deleting part numbers. When I first posted it I saw what happened and edited it to be correct but it still did not like it.

[Freon]

Try reading -
w w w . xpedio . carrier . c o m Slash idc slash groups Slash public Slash documents Slash techlit Slash 58mvb Dash 2pd.pdf
Sorry about the url but it's the only way to post it. Replace Slash and Dash with the symbols.

More info - w w w . xpedio . carrier . c o m Slash idc slash groups Slash public Slash documents Slash techlit Slash

Scroll down to your furnace model.

The motor is an ECM motor and I think the thermostat you need (not the infinity control) may be different than an ordinary thermostat.

[Joedella]

From the info in the link that you posted, the furnace relies on the motor's variable speed ability to enhance its efficiency.
You're right, a 1 stage tstat ain't gonna cut it.
To allow the tstat to affect blower speed in a Carrier furnace, I'll most likely need a Carrier specific tstat.
I don't believe there are any compatibility rules between manufacturers that would allow brand x tstats to provide full functionality in brand y furnaces.

Is an ECM motor the same as a brushless DC motor (BLDC)*

[Freon]

Is an ECM motor the same as a brushless DC motor

Yes.

[Joedella]

Thank you for the great help you have given me. Reading that 20 pg Infinity booklet taught me alot. Thanks again!

One quickee

What's the relationship between Carrier and *

[Freon]

What's the relationship between Carrier and *

Re post but don't use a question mark at the end.