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I have an electric heater in my house. Is there a main filter on the furnace itself? I'm not talking about the hvac filter that costs $20 and you change it every 2 to 3 months.
Is there a second filter on a central heat system?
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For some reason the heater tries to turn on but then stops about 5 seconds later.
Originally Posted by motor_oil_madman
For some reason the heater tries to turn on but then stops about 5 seconds later.
You said "the heater"....does it do the same with A/C? Central HVAC systems usually have both a start capacitor and run capacitor. The run capacitor may need attention. Could be bad altogether or just a loose wire.
Air filter shouldn't have an effect on whether the fan stays on or not. Most will only have one filter at the return side of the unit.
For some reason the heater tries to turn on but then stops about 5 seconds later.
You said "the heater"....does it do the same with A/C? Central HVAC systems usually have both a start capacitor and run capacitor. The run capacitor may need attention. Could be bad altogether or just a loose wire.
Air filter shouldn't have an effect on whether the fan stays on or not. Most will only have one filter at the return side of the unit.
Does the blower come on? Try turning the fan from "auto" to "on", if the blower comes on, then turn on heat & see what happens. Almost sounds like a limit switch problem, either a fan control or high limit.
Originally Posted by motor_oil_madman
I have an electric heater in my house. Is there a main filter on the furnace itself? I'm not talking about the hvac filter that costs $20 and you change it every 2 to 3 months.
Can you post us a picture of this heater? How old is it?
On a Forced air gas heater there are a few things that start to fail. There is a flame rod that gets dirty and needs to be cleaned every few years with a scotch brite otherwise it can cause the furnace to properly work. Other item is the igniter which fails. Other points are the blower motor and heat exchanger.
I have an electric heater in my house. Is there a main filter on the furnace itself? I'm not talking about the hvac filter that costs $20 and you change it every 2 to 3 months.
Can you post us a picture of this heater? How old is it?
On a Forced air gas heater there are a few things that start to fail. There is a flame rod that gets dirty and needs to be cleaned every few years with a scotch brite otherwise it can cause the furnace to properly work. Other item is the igniter which fails. Other points are the blower motor and heat exchanger.
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Many newer HVAC systems have 2 filters, on at the inlet on the wall/ceiling and then one right before the coils.
The first one is usually around 1" thick, the one at the unit is closer to 4-5 inches.
They look like this:
![[Linked Image]](https://www.bobistheoilguy.com/forums/attachments/usergals/2019/10/full-4879-37607-filter.jpg "[Linked Image]")
But as said, it would have nothing to do with the heater not kicking on.
The first one is usually around 1" thick, the one at the unit is closer to 4-5 inches.
They look like this:
But as said, it would have nothing to do with the heater not kicking on.
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I tried turning on the ac and i hear a knocking/rattling sound whenever I turn on the air conditioner. I don't hear the fan turning on. I hear the noise from air intake grate inside the house.
Sounds like the interior blower/fan is not working. If there is no air flow, the heater section will overheat and turn itself off.
Since you hear abnormal mechanical noises, go to the air handler unit and take the fan cover off and investigate for mechanical problems with the fan. Or call in a professional. This is more than a clogged filter.
Since you hear abnormal mechanical noises, go to the air handler unit and take the fan cover off and investigate for mechanical problems with the fan. Or call in a professional. This is more than a clogged filter.
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Originally Posted by bullwinkle
Does the blower come on? Try turning the fan from "auto" to "on", if the blower comes on, then turn on heat & see what happens. Almost sounds like a limit switch problem, either a fan control or high limit.
The fan doesn't seem to want to come on. I switched the option from auto to on and set it to run 55 minutes for every hour. That's the max time. Still nothing.
Does the blower come on? Try turning the fan from "auto" to "on", if the blower comes on, then turn on heat & see what happens. Almost sounds like a limit switch problem, either a fan control or high limit.
The fan doesn't seem to want to come on. I switched the option from auto to on and set it to run 55 minutes for every hour. That's the max time. Still nothing.
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How much is a new blower motor?
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A few days back I turned on the air conditioner and it sounded like it was surging up and down, but then it evened out and ran fine. I don't know if that was the blower because it sounded like the outside unit was also surging.
Originally Posted by motor_oil_madman
How much is a new blower motor?
You've determined that the motor is dead ? You should be aware, there can be multiple components that control whether or not the motor starts first and it could be those that have failed. Not a wise idea to just throw parts at it, especially starting with one of the most expensive in the system.
How much is a new blower motor?
You've determined that the motor is dead ? You should be aware, there can be multiple components that control whether or not the motor starts first and it could be those that have failed. Not a wise idea to just throw parts at it, especially starting with one of the most expensive in the system.
You'd use a multimeter to see if power is getting to the motor. Usually if it uses a start/run capacitor, that will fail before the motor does, unless it's severely clogged with dust (IN the motor, not in the blades), or just very old and the bearings seized but usually it will make a racket spinning before the bearings totally seize. This you can check pretty simply by turning it by hand, with power to it disconnected for safety.
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well I don't know. The heater kicked on and everything sounded/worked normal, but it shut off about a minute later without reaching the set temperature. It was when I turned on the air conditioner that I heard the rattling. I'll call an HVAC guy on Monday.
So the symptoms are simple, the air conditioner rattles and the heater doesn't want to turn on. lol Or turns on when it wants to.
So the symptoms are simple, the air conditioner rattles and the heater doesn't want to turn on. lol Or turns on when it wants to.
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Wellninthinknthere is something wrong since it's making noise.
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Both the heater and air conditioner seem to be working fine now. I don't know what happened.
Older furnaces , like mine , have multi speed " conventional " fan motors . A/C functions at a different fan speed than heat . I read newer / high SEER units have variable speed fan motors with " electronics " ( EXPENSIVE ! ) .
Conventional fan motors have a capacitor that sometimes goes out . Not all that expensive .
As has been said . No or low air movement & the heat source will shut itself off .
Best of luck to you !
Conventional fan motors have a capacitor that sometimes goes out . Not all that expensive .
As has been said . No or low air movement & the heat source will shut itself off .
Best of luck to you !
Originally Posted by motor_oil_madman
Both the heater and air conditioner seem to be working fine now. I don't know what happened.
Is the drain for the AC possibly clogged or frozen? When the system stopped for a while the ice build up melted and you are ok now?
Both the heater and air conditioner seem to be working fine now. I don't know what happened.
Is the drain for the AC possibly clogged or frozen? When the system stopped for a while the ice build up melted and you are ok now?
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