This is what this house has: a gas heater, electric ingiter, fan (blower). This is what's happening: Natural gas is released, electric igniter lights gas (creates heat), blower is activated, heat is blown though venting system. Then, gas expulsion is stopped (thus ceasing HEAT), and fan continues to blow for...oh...30-45 seconds. When the burners stop burning, the fan continues to blow, and we get chilly (not cold) air through the venting system, somewhat defeating the purpose of creating heat. (the house does become warmer, by small increments)The FAN"S INTAKE comes from ducting leading to the roof, outside, fresh air circulation, NOT recycled air circulation. The heater does have it's own fresh air inlet/outlet, as it should.
Shouldn't the BLOWER'S INTAKE come from inside the area to be heated (creating real warmth) as opposed to getting cold air from outside? Why was this system built this way?
If I redirect the blower's intake to recycle the air, what risks am I running?
2006-11-21 08:26:12 · 5 answers · asked by Ryan 4 in Home & Garden ➔ Do It Yourself (DIY)
By drawing air from outside you are not wasting heated air from the house which would be expelled through the exhaust vent. It sounds like you have a high efficiency unit that recirculates the heated air inside the combustion chamber before it is pushed out the exhaust. You might be able to reduce the amount of time the blower continues blowing after the burner shuts off. But trust me, the furnace uses a lot less fuel than the old style ones did. And if you begin it use inside air to feed the furnace, it will go right out the vent which means less heated air stays in the house and cold outside air has to seep into the house to replace it....
2006-11-21 08:48:14 · answer #1 · answered by FAT CAT 4 · 0⤊ 0⤋
You furnace is displaying classic symptoms of shutting down on high limit. You have a blockage in the filter or your return air vents are blocked or you have several vents closed....or your limit sensor/switch is going bad. If you have a high efficiency furnace, it takes in fresh air and exhausts through PVC pipe...just leave these alone....if in fact this is what you have. Check your ductwork for blockage, check your vents and if you don't discover a problem, call a heating tech to check your limit.
HVAC tech for 10 years
2006-11-21 13:15:03 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Being an HVAC tech, i think of you would be mis-describing what is going on and/or confusing nomenclature. enable me take a stab at attempting to describe your subject and you tell me if I’m on the dazzling music. one million)you have a intense performance furnace with probably 2 white plastic pipes leaving it – the two for the time of the roof. 2)someplace on your return air duct is a pipe or versatile duct which introduces exterior clean air into the return air duct. 3)whilst there's a call for warmth from the thermostat, FIRST the small inducer motor (which sucks in combustion air from the exterior and discharges combustion gases to the exterior) starts to function. in basic terms after it extremely is as much as velocity (in many circumstances 10 to fifteen seconds) then SECONDLY, the igniter starts to glow bright orange. After the igniter glows bright orange for a quantity of time, the gas valve launch gas into the combustion chamber. 4)After a era of combustion heat up (in many circumstances 15 to 40 5 seconds), the furnace’s blower (some human beings mistakenly call this the fan) starts to flow heat air for the time of the ductwork. After the furnace’s blower circulates air for a mutually as, the gas valve terminates the flow of gas however the main substantial furnace blower keeps to run. 5)The cycle then repeats itself many circumstances formerly finally friendly the thermostat (as against a relentless ignition and flame till the thermostat is happy). if that's the case, re-positioned up and we are in a position to help you diagnose. Pay specific interest to the nomenclature used!
2016-12-29 07:34:08 · answer #3 · answered by ? 3 · 0⤊ 0⤋
No residential furnace is made to run on 100% outside air. Are you sure you are not looking at combustion air intake.
2006-11-21 09:53:30 · answer #4 · answered by Controlfreak38 6 · 0⤊ 0⤋
you should check any filters or coils in your system. it sounds like your furnace is running off on high limit, which means it hits its maximum temp quickly thus shutting down the burner. you must have sufficient airflow to keep it from hitting the limit.
2006-11-21 08:36:19 · answer #5 · answered by bikeguy 2 · 2⤊ 0⤋