I just recapped my A/C. Or rather, the tech did it under warranty.
Why the frell haven‘t A/C motor run caps all switched over to MKPs????? Effing ceiling fans use MKPs these days. So does my washing machine and refrigerator. But the motor that draws the highest amperage, and has to work in the highest ambient temperature?
Why the frell haven‘t A/C motor run caps all switched over to MKPs????? Effing ceiling fans use MKPs these days. So does my washing machine and refrigerator. But the motor that draws the highest amperage, and has to work in the highest ambient temperature?
If it was a regular old style A/c, the caps are quite high value for MKP style, the LRA - locked rotor amps - can be 45 A for a piston type and 30 A for a rotary 1.5 ton / 18000 BTU compressor.
So every time it starts, 3 times an hour or more, it has to give that big a current.
The oil filled capacitors can last 10+ years, I have yet to see such high rated MKP caps here, and they can be, shall we say, of variable quality.
I replaced the ones in my unit after many years, both the start and run caps, and the relay, cost me about $10 in total and a lot of sweat.
The shop gave me a Chinese made run cap, sold as a service part by Carrier, so some assurance of quality was there compared to the no - name (or obscure name) caps sold in the market here at A/c parts stores.
The unit dates to 1992, second recap so far.
But a cap replacement under warranty is, well, unusual...
The newer units are all 'inverter' (BLDC) drives, the drive is in the outdoor unit, mostly without PCB coating, they have a high probability of failure within 5 years.
One voltage spike, and most fail, the repair cost is more than the energy saved by using the drive type units.
And in some cases, the drives are not available, have to scrap the A/c.
But the ladies in particular want to boast that they have the latest '5 Star' (energy efficiency rating) units....fashion!
Not seen one with VFD AC drive so far, should be reliable.
So every time it starts, 3 times an hour or more, it has to give that big a current.
The oil filled capacitors can last 10+ years, I have yet to see such high rated MKP caps here, and they can be, shall we say, of variable quality.
I replaced the ones in my unit after many years, both the start and run caps, and the relay, cost me about $10 in total and a lot of sweat.
The shop gave me a Chinese made run cap, sold as a service part by Carrier, so some assurance of quality was there compared to the no - name (or obscure name) caps sold in the market here at A/c parts stores.
The unit dates to 1992, second recap so far.
But a cap replacement under warranty is, well, unusual...
The newer units are all 'inverter' (BLDC) drives, the drive is in the outdoor unit, mostly without PCB coating, they have a high probability of failure within 5 years.
One voltage spike, and most fail, the repair cost is more than the energy saved by using the drive type units.
And in some cases, the drives are not available, have to scrap the A/c.
But the ladies in particular want to boast that they have the latest '5 Star' (energy efficiency rating) units....fashion!
Not seen one with VFD AC drive so far, should be reliable.
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Even QSC amps get more than 4 years out of a set of capacitors (99% of the time that’s what fails). The unit was installed 4 years ago, highest SEER unit that still has a real AC induction motor. Professionally installed, payed out the ***. It’s predecessor’s electronics went haywire when the reversing valve seized - would have been over 5 grand to fix. In todays units if the electronics doesn’t fail right at 10 years, the aluminum tubing develops leaks (or other problems) right at the interface of dissimilar metals. This unit will become the next owner’s problem at that time.
But I don’t want a $20,000 problem occurring every 10 years at the new build. Considering going with two pre-charged mini split units (3 and 2 ton, seven zones total). I wouldn’t expect those to last much more than 10 years, but the cost of replacement is far less because you don’t pay the 2X markup that calling in someone with a license to handle refrigerants costs. With two units (and a separate central propane furnace which lasts forever) there is no single point of failure. You stay in the rooms that still get cooled, or switch to gas in the winter till the unit gets replaced. Total installed cost will run less too - the only ***-whooping will be having someone hook up the gas lines. The shop (500 sq ft, insulated like a thermos) is getting a 1.5 ton mini split regardless - one of those runs about what two 11 SEER window units does, and those only last about 5 years each.
But I don’t want a $20,000 problem occurring every 10 years at the new build. Considering going with two pre-charged mini split units (3 and 2 ton, seven zones total). I wouldn’t expect those to last much more than 10 years, but the cost of replacement is far less because you don’t pay the 2X markup that calling in someone with a license to handle refrigerants costs. With two units (and a separate central propane furnace which lasts forever) there is no single point of failure. You stay in the rooms that still get cooled, or switch to gas in the winter till the unit gets replaced. Total installed cost will run less too - the only ***-whooping will be having someone hook up the gas lines. The shop (500 sq ft, insulated like a thermos) is getting a 1.5 ton mini split regardless - one of those runs about what two 11 SEER window units does, and those only last about 5 years each.
Rebushed the wheel bearings on the wife's Victorian or Edwardian hand cart.
I fully restored it a couple of years ago. It was in a pretty bad state.
We bought it at a local Brocante.
The wheels and axle were very serviceable though - main thing..
She uses it to put her home grown flower bouquets out on.
It does a fair few miles across our large gravel drive every year.
I fully restored it a couple of years ago. It was in a pretty bad state.
We bought it at a local Brocante.
The wheels and axle were very serviceable though - main thing..
She uses it to put her home grown flower bouquets out on.
It does a fair few miles across our large gravel drive every year.
Put rubber strips around the rims, like tires, the noise and vibration will reduce.
I designed a low frequency dula channel USB PC oscilloscope.
It uses two 10MHz A2D's and a PIC processor.
Managed to get 6 mega samples per second total which was a bit disappointing but I am multiplexing outputs of A2D's into the PIC which takes time.
I cant find a through hole PIC that has enough pins to do it none multiplexed.
Revisited it today and tried some 74AC157 multiplexers which are faster than the previous ones.
Managed to push it up to 7 mega samples per second so a small improvement.
It uses two 10MHz A2D's and a PIC processor.
Managed to get 6 mega samples per second total which was a bit disappointing but I am multiplexing outputs of A2D's into the PIC which takes time.
I cant find a through hole PIC that has enough pins to do it none multiplexed.
Revisited it today and tried some 74AC157 multiplexers which are faster than the previous ones.
Managed to push it up to 7 mega samples per second so a small improvement.
Not as much of a repair as a refresh?
The kitchen got some love in the way of new paint, floor tiles, back splash tiles, shelving, lighting, and a pot rack. Oh also a triple bin garbage can that was found thrown away in the garbage (An aside: Have you even wondered how you would get the garbage collector to take away a garbage can as garbage instead of leaving it behind?).
I'm crap at taking before and after photos so of course I didn't take one so the before is from April.
The kitchen got some love in the way of new paint, floor tiles, back splash tiles, shelving, lighting, and a pot rack. Oh also a triple bin garbage can that was found thrown away in the garbage (An aside: Have you even wondered how you would get the garbage collector to take away a garbage can as garbage instead of leaving it behind?).
I'm crap at taking before and after photos so of course I didn't take one so the before is from April.
2 Samsung TV's - both needed the main PSU cap replaced - 2$ each.
Fixed my door frame with a hammer, a 3/8 extension bar, and an angle grinder... Now the door closes without catching on the frame.
I "fixed" the ground loop between a stack of amplifiers and the preamp that drives them by running it all from the same circuit using an extension cord. It works better than the AD/DA solution I was using before.
I fixed one of the safety railings on the roof of the building with 2 screws.
I'm still working on fixing my 10 year long relationship... but sadly, it's looking more and more like it's bitched, and not by my choice.
Fixed my door frame with a hammer, a 3/8 extension bar, and an angle grinder... Now the door closes without catching on the frame.
I "fixed" the ground loop between a stack of amplifiers and the preamp that drives them by running it all from the same circuit using an extension cord. It works better than the AD/DA solution I was using before.
I fixed one of the safety railings on the roof of the building with 2 screws.
I'm still working on fixing my 10 year long relationship... but sadly, it's looking more and more like it's bitched, and not by my choice.
That’s a REALLY nice job, but I think I’d get dizzy and crash into something. It’s certainly a one-person-and-NO-DOG(s) space. There would be a collision at the plate over food, for sure.
My car speakers are total junk on my 20 years old Renault.
All four of them have their cone turned into dust, most arount the edge.
Those are 17cm, I need 4.
Any idea for not so bad 17cm car speakers ?
All four of them have their cone turned into dust, most arount the edge.
Those are 17cm, I need 4.
Any idea for not so bad 17cm car speakers ?
I'm currently trying to fix the HV battery in my wife's 2005 Prius. Did already 3 months ago but at that time I didn't think about the capacity of cells so I just replaced the one that measured low in my Hybrid Assistant app. It costed me 15€ and a few days (dismantling, understanding, balancing...) and was enough for her to drive 7000km.
But it went wrong again, so I decided to make it seriously. It appears that 4 modules are really not good, so I'm replacing them. But waiting for the right modules to be shipped, I'm trying to "reform" them if they're not too crappy.
What's interesting is that as soon as you read and think, things become clearer. I knew next to nothing about NiMh batteries 3 months ago (even if I own an old Prius myself), and I'm able to see now which module I can keep, which I can "reform", and which will never be used in a car again...
Picture of my temporary and to be improved installation:
And last Sunday I replaced the iPhone XS's screen for a friend's kid.
But it went wrong again, so I decided to make it seriously. It appears that 4 modules are really not good, so I'm replacing them. But waiting for the right modules to be shipped, I'm trying to "reform" them if they're not too crappy.
What's interesting is that as soon as you read and think, things become clearer. I knew next to nothing about NiMh batteries 3 months ago (even if I own an old Prius myself), and I'm able to see now which module I can keep, which I can "reform", and which will never be used in a car again...
Picture of my temporary and to be improved installation:
And last Sunday I replaced the iPhone XS's screen for a friend's kid.
