Duct work use to be sheet metal for everything. Now its flex ductwork and that can be torn or crushed much more easily. A connection could have opened up a side.Someone needs to inspect all the ductwork.
Home heating issues - poor airflow
- Thread starter Quattro Pete
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Flex duct works ok if it is pulled tight and clamped firmly on both ends, but if its not pulled tight or is sagging anywhere it is held up, the airflow is terrible. We had some in our old house and I ripped it out and replaced it with insulated hard ducting and the difference in flow was night and day from those vents.
Anyway, funny this thread pops up today. When I woke up yesterday the house was chilly, but it was -6F outside according to my phone so I expected it to feel cooler than normal. The thermostat was at 67, which is what I turn it down to at night, and that always feels cool to me. Grabbed my stuff and headed to work.
Wife calls me about three hours later, said the house is freezing (58 degrees F, she had the thermostat at 72) and the furnace is short cycling, turning on then turning off about 10-15 seconds later. I thought I had heard it short cycle like that a couple times the previous night, but I didnt think too much of it because it was pretty warm where I was watching TV so it didnt really phase me much.
So anyway I drove the 34 miles back home and yup, its cold in here and I can hear the furnace short cycling about five times already in the few minutes I have been home. Air coming that was briefly coming out of the vents between cycles was pretty warm, but weak in flow. Went down into the dungeon and shut off power to the furnace and started checking things. Opened the filter slot and couldnt even pull it out. It had bowed in toward the blower, so I grabbed a long screwdriver and ripped it out of there. It was caked in dust, even though it was only a few months old. I only knew that because I was beating on it with my screwdriver and dust was flying, otherwise I wouldnt have known because it was one of those anti-allergy ones that have the black charcoal in them. They always seemed like they would be restrictive so I never bought one personally, but we just moved in the first of November and it was brand new right before we took possession of the house so I just left it in there. I guess the combination of them moving out and us moving in, we must have stirred up a lot of dust.
New filter from Walley World, threw it in, turned power back on and set the thermostat to 70....house temperature starting climbing right away and the furnace kept chugging along. About an hour later it felt downright toasty and not one short cycle. It was fine the rest of the day and today its been fine as well.
In my previous house with the heat pump I could go 7-8 months easy without servicing the filter. Wont be doing that in this house.
Anyway, funny this thread pops up today. When I woke up yesterday the house was chilly, but it was -6F outside according to my phone so I expected it to feel cooler than normal. The thermostat was at 67, which is what I turn it down to at night, and that always feels cool to me. Grabbed my stuff and headed to work.
Wife calls me about three hours later, said the house is freezing (58 degrees F, she had the thermostat at 72) and the furnace is short cycling, turning on then turning off about 10-15 seconds later. I thought I had heard it short cycle like that a couple times the previous night, but I didnt think too much of it because it was pretty warm where I was watching TV so it didnt really phase me much.
So anyway I drove the 34 miles back home and yup, its cold in here and I can hear the furnace short cycling about five times already in the few minutes I have been home. Air coming that was briefly coming out of the vents between cycles was pretty warm, but weak in flow. Went down into the dungeon and shut off power to the furnace and started checking things. Opened the filter slot and couldnt even pull it out. It had bowed in toward the blower, so I grabbed a long screwdriver and ripped it out of there. It was caked in dust, even though it was only a few months old. I only knew that because I was beating on it with my screwdriver and dust was flying, otherwise I wouldnt have known because it was one of those anti-allergy ones that have the black charcoal in them. They always seemed like they would be restrictive so I never bought one personally, but we just moved in the first of November and it was brand new right before we took possession of the house so I just left it in there. I guess the combination of them moving out and us moving in, we must have stirred up a lot of dust.
New filter from Walley World, threw it in, turned power back on and set the thermostat to 70....house temperature starting climbing right away and the furnace kept chugging along. About an hour later it felt downright toasty and not one short cycle. It was fine the rest of the day and today its been fine as well.
In my previous house with the heat pump I could go 7-8 months easy without servicing the filter. Wont be doing that in this house.
Originally Posted by quint
Opened the filter slot and couldnt even pull it out. It had bowed in toward the blower, so I grabbed a long screwdriver and ripped it out of there. It was caked in dust, even though it was only a few months old. I only knew that because I was beating on it with my screwdriver and dust was flying, otherwise I wouldnt have known because it was one of those anti-allergy ones that have the black charcoal in them. They always seemed like they would be restrictive so I never bought one personally, but we just moved in the first of November and it was brand new right before we took possession of the house so I just left it in there. I guess the combination of them moving out and us moving in, we must have stirred up a lot of dust.
New filter from Walley World, threw it in, turned power back on and set the thermostat to 70....house temperature starting climbing right away and the furnace kept chugging along. About an hour later it felt downright toasty and not one short cycle. It was fine the rest of the day and today its been fine as well.
In my previous house with the heat pump I could go 7-8 months easy without servicing the filter. Wont be doing that in this house.
You should have posted a pic of the old filter. I think I need to check mine tonight, my nest thermostat is showing that some days the furnace comes on for 12 hours a day.
Opened the filter slot and couldnt even pull it out. It had bowed in toward the blower, so I grabbed a long screwdriver and ripped it out of there. It was caked in dust, even though it was only a few months old. I only knew that because I was beating on it with my screwdriver and dust was flying, otherwise I wouldnt have known because it was one of those anti-allergy ones that have the black charcoal in them. They always seemed like they would be restrictive so I never bought one personally, but we just moved in the first of November and it was brand new right before we took possession of the house so I just left it in there. I guess the combination of them moving out and us moving in, we must have stirred up a lot of dust.
New filter from Walley World, threw it in, turned power back on and set the thermostat to 70....house temperature starting climbing right away and the furnace kept chugging along. About an hour later it felt downright toasty and not one short cycle. It was fine the rest of the day and today its been fine as well.
In my previous house with the heat pump I could go 7-8 months easy without servicing the filter. Wont be doing that in this house.
You should have posted a pic of the old filter. I think I need to check mine tonight, my nest thermostat is showing that some days the furnace comes on for 12 hours a day.
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Originally Posted by CT8
It is real cold. The heater is working hard.
There is a difference between working hard and not producing any airflow, which was the issue in my case.
Anyway, problem solved. Thanks everyone.
It is real cold. The heater is working hard.
There is a difference between working hard and not producing any airflow, which was the issue in my case.
Anyway, problem solved. Thanks everyone.
Use RO water or distilled if you are using an ultrasonic humidifier.
(tap water will leave white powder all over)
if you have the old wick style humidifier its not necessary.
For example my basic RO setup reduces the water from ~~300ppm to under 30ppm (without the tank it was reading 6ppm)
(tap water will leave white powder all over)
if you have the old wick style humidifier its not necessary.
For example my basic RO setup reduces the water from ~~300ppm to under 30ppm (without the tank it was reading 6ppm)
If you have air conditioning the evaporator coil could be dirty. Restricting air flow. Common with pets and when using fiberglass filters. I have had some so dirty had to pull them out to clean them. Dog/cat hair, dust coat coil like lint filter on dryer. Have peeled hair and dust off coil. Then spray with foaming coil cleaner. If that didn't clean it, pull and take outside. Spray with acid or alkaline coil cleaner and rinse with water hose. Then reinstall coil.
I removed humidifier in our 20yo forced ha for same reason. Well water minerals blocking. That and supposedly unhealthy.
You shouldn't be getting enough humidifier mineral deposits on a filter to clog it in a month, "IF" that is the cause I would dial way back the humidity setting on it or if the measured humidity level is correct, do one of the other methods mentioned in the article. Otherwise those deposits are going to build up in your furnace, on your A-coil (if you have one), on the heat exchanger, basically everywhere. Long term mineral deposits are not fun to clean off, particularly bare metal surfaces where an acid cleaner can do damage.
Originally Posted by Quattro Pete
Maintenance guy came over, looked over the furnace, and concluded that it's working fine. He said it's the extreme cold that we've been having that may be responsible for what I'm seeing. Somehow, I am not convinced.
My first thought from the first post was "check the air filter first." But then the first post said the maintenance guy looked things over. But then apparently the problem turned out to be the air filter. I hope the OP didn't have to pay for the maintenance guy's expert advice.
Someone mentioned a snake camera/borescope. Those can be pretty cool to have for various uses. Note you can get ones with a screen, but the cheaper ones are often cheaper because they use your phone for the screen, which also has the benefit of usually being a better screen anyway, and also may have wifi/bluetooth capability. The pro ones can be surprisingly expensive, as can be the cost to have a pro come out and use one for an hour.
Maintenance guy came over, looked over the furnace, and concluded that it's working fine. He said it's the extreme cold that we've been having that may be responsible for what I'm seeing. Somehow, I am not convinced.
My first thought from the first post was "check the air filter first." But then the first post said the maintenance guy looked things over. But then apparently the problem turned out to be the air filter. I hope the OP didn't have to pay for the maintenance guy's expert advice.
Someone mentioned a snake camera/borescope. Those can be pretty cool to have for various uses. Note you can get ones with a screen, but the cheaper ones are often cheaper because they use your phone for the screen, which also has the benefit of usually being a better screen anyway, and also may have wifi/bluetooth capability. The pro ones can be surprisingly expensive, as can be the cost to have a pro come out and use one for an hour.
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