Hopefully someone here actually has studied these newer units. Quick story; Built house 2 years ago. 4 ton downstairs,hybrid, 4 ton upstairs/heat pump. Both units about 18 seer. Downstairs unit; flawless, cannot hear run, 2 stage copeland ramps up and down as it should, works great.
Upstairs, since install has blown like crazy, too much, you can dry your hair under a register. Nothing closed off, all runs nice, no bends etc...
Intake is sized to a 20x30. I run only fiberglass/non restrictive filters.
At two years blower motor goes. Mind you our house is very efficient, these units don't have to work often even on 95F days with 85% humidity outside.
My contractor is a good guy, been in the bus. for 40+ years. I call him and say I don't think the motor should have blown, he replies, it's electrical, anything can go...I agreed but...I also know it should not have been blowing as hard on Hi the way it does. He comes out with his guys to check the dipswitches on the air handler. They supposedly are setup so Hi should blow around 1500cfm. Second time they've checked the dipswitches.
This does nothing and even they agree the flex shouldn't be swelling the way it is. They come back the next week with something they never knew; the thermostat has to be set right with the right program, trim etc..Well they did that and thought that was the fix. We set it to cool about 5 degrees below room temp, it ramps to high, sounded okay but then after about 8 min it ramps up like a freight train.
So, rep for goodman says the blower motor windings will heat up due to restriction(or static pressure) and increase CFM to compensate for a dirty filter. They also say that this particular model air handler can be set to a 4 or 5 ton but it must be sized for a 5 ton. Contractor doesn't believe him....although my ductwork and runs are sized for a 4 ton. The tech for the contracting company thinks now it's an issue with the thermostat. I don't because the thermostat responds the way it should and seems to take commands and setting as it should.
All of the above said does anyone know with these air handlers, Goodman/Amana number: DSZC180481, have to be sized to a 5 ton even if you only need a 4 ton supply...? I think they have you size the ductwork to a 5 ton to make up for the variability if you have a filter restriction. This would explain the premature blower motor failure, the flex swell and the enormous amount of air coming thru my registers. I think the motor senses the restriction and after it heats up it ramps up further trying to provide more air flow...? Logical to me but I'm no expert:gah:
Upstairs, since install has blown like crazy, too much, you can dry your hair under a register. Nothing closed off, all runs nice, no bends etc...
Intake is sized to a 20x30. I run only fiberglass/non restrictive filters.
At two years blower motor goes. Mind you our house is very efficient, these units don't have to work often even on 95F days with 85% humidity outside.
My contractor is a good guy, been in the bus. for 40+ years. I call him and say I don't think the motor should have blown, he replies, it's electrical, anything can go...I agreed but...I also know it should not have been blowing as hard on Hi the way it does. He comes out with his guys to check the dipswitches on the air handler. They supposedly are setup so Hi should blow around 1500cfm. Second time they've checked the dipswitches.
This does nothing and even they agree the flex shouldn't be swelling the way it is. They come back the next week with something they never knew; the thermostat has to be set right with the right program, trim etc..Well they did that and thought that was the fix. We set it to cool about 5 degrees below room temp, it ramps to high, sounded okay but then after about 8 min it ramps up like a freight train.
So, rep for goodman says the blower motor windings will heat up due to restriction(or static pressure) and increase CFM to compensate for a dirty filter. They also say that this particular model air handler can be set to a 4 or 5 ton but it must be sized for a 5 ton. Contractor doesn't believe him....although my ductwork and runs are sized for a 4 ton. The tech for the contracting company thinks now it's an issue with the thermostat. I don't because the thermostat responds the way it should and seems to take commands and setting as it should.
All of the above said does anyone know with these air handlers, Goodman/Amana number: DSZC180481, have to be sized to a 5 ton even if you only need a 4 ton supply...? I think they have you size the ductwork to a 5 ton to make up for the variability if you have a filter restriction. This would explain the premature blower motor failure, the flex swell and the enormous amount of air coming thru my registers. I think the motor senses the restriction and after it heats up it ramps up further trying to provide more air flow...? Logical to me but I'm no expert:gah:
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