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Re: furnace keeps running, no heat
The pressure switch is not allowing the igniter to heat up. Pressure switch is blocked or the flue is blocked. Take the draft fan off and inspect the flue. Also inspect the rubber hose connecting the fan and pressure switch make sure the ends are tight. Make sure the hose is clear and not restricted. And the pressure switch sometimes is position sensitive. I don't think it has been moved or anything. And very rarely do they go bad.
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You are using too restrictive of an air filter. If the codes you are getting off the lights says anything about a high limit this is the cause of your blower running all the time. Use a less restrictive filter or have your contractor install a media filter in the system. if you reset the furnace and it does not stop running the blower you have a stuck limit switch and may have to get another or call a service tech to reset it or replace.
Your humidifier is a bypass type. The only voltage needed is 24vac to open the water valve. Air only flows through the humidifier when the furnace blower is running, and the wet pad will add very little humidity if the furnace is not running and heating the air before flowing through the wet pad in the humidifier.
It is best the water valve is only energized when the furnace is running. Some furnaces have a connector on their control boards labeled HUM for this purpose. Test it's voltage when the furnace is running because some will output 110vac instead of 24vac you need.
Neither, even if the solenoid or humidistat stick, it should always drain properly. Is the unit mounted on the cold air return duct or the supply plenum? If it's mounted on the supply plenum, the water panel might be getting blown forward and spilling the water. High efficient furnaces also can leak water on the floor if its drain is restricted. If hum. is mounted on return duct make sure drain is clear by blowing through it. On Honeywell hum's I've seen the rubber hose from the solenoid valve to the distributor tray leak too, check the rubber 1/4" hose.
The first thing to check would be the filters in the house to make sure they are clean, then check for any blockage. One easy way of seeing if the airflow is good, just put your hands in front of a vent and see how its blowing. Your furnace has what you would call sensors, and if they sense the air flow is inaccurate or to hot inside the unit, the unit will run, but not light. Also, if it tries to relight to many times, the furnace will go into lock out and you have to manually reset it by cutting the power to the furnace. Its kinda hard to diagnose these sometimes over the pc, but I hope it helps.
It is possible that you did not set the new blower on the proper speed. Black wire is high. Blue is medium. Red is low. If the fan is operating to slow it can run to hot and trip the high limit control. Make sure the filters are clean. When the old motor went bad, the problem might not have been discovered rite away your high limit control might need to be changed.
Also anytime you work on a furnace you can kick up some dust. Always clean the flame sensor.
I am not a furnace guy but I may be able to give you a few ideas of things to diagnose the problem and get it resolved. First off, I assume you have a thermostat that you use to to turn your heat on. If it is a generic ( meaning : non programmable model) then you should be able to try this simple test. Remove the cover ( typically they snap on) around the thermostat so you can see the control mechanism inside. You should see few skinny wires ( similar to those used on a telephone wire) solid copper in various colors.. When you rotate the dial on your thermostat to call for heat, there is a small glass vial that has a drop of mercury ( which is electrically conductive) in it that makes contact and shorts two control wires together ad that is what calls for heat on your furnace. When the temp inside the room where the thermostat is reaches the tempertaure you requested, the bimetal mechanism either contracts or expands to reposition that glass vial to shift the mercury off the contacts and your furnace shuts off... That is the basics behind how your thermostat and furnace work ( generally speaking) If you can identify the two wires inside the thermosat that are shorted together when that vial of mercury shorts them inside it.. you can temproarily unhook them ( they are low voltage.. normally 24 Volts or less) so no worries about getting ashock or anything.. and short them together for a minute or two.. by doing that... your furnace should turn on and heat should flow.... Once you start your furnace this way.. unhook these two wires and your furnace should shut down .. It may take a minute or two ( depending on the control for it) If it doesn't..then your problem is on the furnace side and you may need to get the furnace control system serviced or replaced.. if it does shut down, then your problem is your thermostat and thats a simple replacement.. Also.. make sure the thermostat was properly leveled on its base.. The position of the thermostat ( meaning level) will dictate when that mercury makes contact and your furnace switches on.. OK..I tried to explain the works of this to you but here is a link to a Honeywell site that explains it in simpler terms.. The part about shorting the two wires together and then opening them will aid you in identifying where the problem actually is.. here is the link: http://homerepair.about.com/od/heatingcoolingrepair/ss/thermostat.htm
Hope this helps you more than confuses you..
You can try installing the water line to your hot water if it is installed on cold line for more humidification. You should make sure your humidistat is up line 6" @least from humidifier for proper humidification measurement.