Home Repair (alt.home.repair) For all homeowners and DIYers with many experienced tradesmen. Solve your toughest home fix-it problems.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
joe
 
Posts: n/a
Default Furnace Question - master switch vs thermostat

Too often, and unpredictably, when the thermostat tells our gas furnace to
turn on, all that turns on is the fan that exhausts the moisture from the
combustion. It is not followed up with the flow and ignition of the gas.

If I flip off the master switch that controls power to the furnace, and
flip it back on after a short time, the fan starts up, and the ignition
always occurs.

But if I go to the thermostat and raise the temperature there, by
breathing on it, for example, that shuts the furnace off; but when the
temperature at the thermostat drops back to the ambient temperature, and
the fan starts up again, ignition never occurs.

So it looks like there is a difference in what is shut off by the master
switch and by the thermostat, and that the problem has something to do
with that.

Any suggestions?
  #2   Report Post  
RBM
 
Posts: n/a
Default

There was a situation posted about a week ago, similar to yours. There is a
really sharp guy called "hvactech2" who explained that this is called "lock
out" which occurs when there is a problem sensed by the board in the
furnace. By turning off the power and then back on, it will reset the unit,
until it senses the fault again and locks out
"joe" wrote in message
news
Too often, and unpredictably, when the thermostat tells our gas furnace to
turn on, all that turns on is the fan that exhausts the moisture from the
combustion. It is not followed up with the flow and ignition of the gas.

If I flip off the master switch that controls power to the furnace, and
flip it back on after a short time, the fan starts up, and the ignition
always occurs.

But if I go to the thermostat and raise the temperature there, by
breathing on it, for example, that shuts the furnace off; but when the
temperature at the thermostat drops back to the ambient temperature, and
the fan starts up again, ignition never occurs.

So it looks like there is a difference in what is shut off by the master
switch and by the thermostat, and that the problem has something to do
with that.

Any suggestions?



  #3   Report Post  
Bubba
 
Posts: n/a
Default

Which means:
Get it fixed because there IS a problem. Dont wait till its 0 outside
or you go away for a weekend. Turning the power off to the furnace
resets the circuit board, basically like rebooting the computer. It
keeps reoccuring because there is a "fault" happening within the
furnace or vent piping.
Turning the stat off does not reset anything because it does not
restet the power to the main circuit board.
Bubba

On Sun, 23 Jan 2005 10:41:49 -0500, "RBM" rmottola1(remove
wrote:

There was a situation posted about a week ago, similar to yours. There is a
really sharp guy called "hvactech2" who explained that this is called "lock
out" which occurs when there is a problem sensed by the board in the
furnace. By turning off the power and then back on, it will reset the unit,
until it senses the fault again and locks out
"joe" wrote in message
news
Too often, and unpredictably, when the thermostat tells our gas furnace to
turn on, all that turns on is the fan that exhausts the moisture from the
combustion. It is not followed up with the flow and ignition of the gas.

If I flip off the master switch that controls power to the furnace, and
flip it back on after a short time, the fan starts up, and the ignition
always occurs.

But if I go to the thermostat and raise the temperature there, by
breathing on it, for example, that shuts the furnace off; but when the
temperature at the thermostat drops back to the ambient temperature, and
the fan starts up again, ignition never occurs.

So it looks like there is a difference in what is shut off by the master
switch and by the thermostat, and that the problem has something to do
with that.

Any suggestions?



Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Noob question about pilot light on gas furnace NWM Home Repair 14 November 22nd 04 11:26 AM
Old Oil Furnace Efficiency Question Vito Cavallo Home Repair 4 November 10th 04 02:07 PM
Flourescent Lamp switch Question. PaPaPeng Electronics Repair 5 October 26th 04 11:03 PM
how to rewire bathroom pull switch to regular light switch Nick UK diy 20 January 20th 04 08:57 PM
Installing boiler thermostat question David Hearn UK diy 5 December 3rd 03 10:03 PM


All times are GMT +1. The time now is 05:12 PM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"