#2 Sanyo 24KHS72 AC/HP Install Project (Oct 2011)

[Xringer]

There is a 'Heater' label beside that big relay. But, I've still been looking at that relay as a suspected 230 AC power provider for those big diodes.
I made a reference pic, with an inversion on the right side.
I'll have to take my tablet outside with me.. Get there before the sun does..


What do you think TH02 is?

[WyrTwister]

I am a little confused by the white neutral , if it is part of the incoming 240 VAC . Normally , we do not bring a neutral to this type / voltage HVAC equipment . Two hots and one earth ground / equipment grounding conductor . ( And I see the green ground . ) No neutral because usually , such equipment has no 120 VAC load .

Unless the neutral is generated by the electronics ?

Also confused by the single glass fuse on the incoming AC power . We fuse or circuit breaker both ( or all 3 hots ) . I know this is a long shot , but take this , and any other fuse out of the circuit , and use an ohm meter to test it .

That would really be a cheap fix .

Two white wired going up to the top of the photo . Fan ?

Brown & white going to the capacitor area . White BD- and the other , brown , I can not see .

W , V and U are by the blue cap , upper right . Three power leads to the compressor .

The components covered with white heat transfer grease , what were they transferring heat to , a piece of sheet metal stuck to their tops ?

For me , very much a puzzle .

God bless
Wyr

[WyrTwister]

Guessing heat is either a crankcase heater or a heater at the bottom of the sheet metal pan , to keep the defrost water from freezing before it can drain .

God bless
Wyr

[Xringer]

Originally Posted by WyrTwister

I am a little confused by the white neutral , if it is part of the incoming 240 VAC . Normally , we do not bring a neutral to this type / voltage HVAC equipment . Two hots and one earth ground / equipment grounding conductor . ( And I see the green ground . ) No neutral because usually , such equipment has no 120 VAC load .

Unless the neutral is generated by the electronics ?

Also confused by the single glass fuse on the incoming AC power . We fuse or circuit breaker both ( or all 3 hots ) . I know this is a long shot , but take this , and any other fuse out of the circuit , and use an ohm meter to test it .

That would really be a cheap fix .

Two white wired going up to the top of the photo . Fan ?

Brown & white going to the capacitor area . White BD- and the other , brown , I can not see .

W , V and U are by the blue cap , upper right . Three power leads to the compressor .

The components covered with white heat transfer grease , what were they transferring heat to , a piece of sheet metal stuck to their tops ?

For me , very much a puzzle .

God bless
Wyr

I've been looking for any more fuses.. So far they are all good..
Not many more places they can hide.

The heat sink hangs upside down, under the controller board..
http://i46.photobucket.com/albums/f1...001smaller.jpg

That black box on the floor, is the Reactor! Yeppers..

[WyrTwister]

Sanyo Outdoor Photo by Xringer | Photobucket

Is this the drawing for your unit or a generic outdoor unit ?

God bless
Wyr

[jeff5may]

Xringer,

Good eye seeing TH02. It looks to be a thermistor (probably PTC like a deGaussing coil in a crt tv) wired across that mains relay. It could be the standby power bleeder component that bootstraps the rectifier bridge with just a little power. Then again, it could be just an inrush current limiter for when the power is applied(to precharge the big caps). Either way, since it is there, you should have some current bleeding through to that rectifier bridge and PFC network (enough to get 12-15 volt standby b+ and maybe regulated 5V out of the tinyswitch).

I found a pdf on the compressor speed controller:

https://www.fairchildsemi.com/applic...AN/AN-9044.pdf

Fairchild/TI has sister chips that do the PFC correction in tandem with the speed controller chips, that contain the diode bridge and IGBT as well. I guess Sanyo figured the chips cost more than discrete components in this unit. Lucky us.


Wyr,
Most of these consumer-grade appliances are fused and such like a clothes dryer. If they have a neutral wired in besides an earth ground, it is sometimes used and sometimes not. Like the old-school egg timer dryers, the timers usually run between one line and the neutral. The internal fuse is pretty much for fire prevention in case of a dead short somewhere inside the chassis. These appliances are all meant to be protected at the incoming power source with some kind of breaker or disconnect. The neutral wire is loosely coupled to the earth ground with a fireproof component of some kind, Xringer identified a lightning arrestor (high-tech neon light) in this unit earlier.

I'm sure there is a MOV or some kind of HV cap between all of the incoming power and earth connections and spark gaps and such very close to where they jump into the board. All that crap has to be there for the OEM to get FCC and CSA/UL approval. More than a few manufacturers (Sony, Mitsubishi, Philips especially) for designing their "insurance circuitry" so that it commits suicide any time the incoming power goes awry. When I worked at a repair shop in town, I loved thunderstorms. I could count on some dead WEGA's or Diamondtron's coming through the door the very same day under extended warranty.

[Xringer]

Originally Posted by WyrTwister

Sanyo Outdoor Photo by Xringer | Photobucket

Is this the drawing for your unit or a generic outdoor unit ?

God bless
Wyr

That's mine. It's the basic wiring of the main board.
Mine has been hacked to add a 10A auto-breaker. (upper right corner).
http://i46.photobucket.com/albums/f1...L/Untitled.jpg
It's working fine, putting all kinds of 240vac on the PCB..

[Xringer]

Nice work Jeff.. I guess you do this for a living.?.
That PWM Transistor is Q01? (Middle left on the board)?
http://ecorenovator.org/forum/attach...-p1030408c-jpg

Seems like a very good place to check for HV DC..

I saw the BootStrap info in the file. I'll have to read it when I get back home after lunch.
It's CandlePin bowling day.. My Boston wife wants to kick my Texas butt again..

[jeff5may]

Used to. Nobody really gets their stuff repaired any more. With new equipment selling for not much more than the repair price, it just doesn't make much sense any more. Plus, flat TV's are all screen. If the screen has problems, It's not worth repairing. Sometimes replacement panels cost more than a new tv. The only exceptions are pro audio stuff and tube amps.

[WyrTwister]

I understand about the cloths dryer . Old school , 2 hots and a wire that was essentially a neutral , but was sometimes bonded to the frame of the appliance . I think the old mechanical - electric timers were 120 VAC , and if they had any lamps , they were probably 120 VAC , also .

For quite a few years , they have been required to have 4 wire source , 2 hots , 1 neutral and 1 earth ground / equipment grounding conductor .

Today , in my world , the neutral and the earth ground are 2 separate entities , with a bonding jumper at the service entrance panel .

One of the diagrams you , or Xinger posted , indicates the presence of a power relay . Voltage , from Terminal #6 passes through an overload relay and a high pressure switch , to the power relay coil .

When the power relay closes , one of the hots ( terminal # 5 ) passed through the closed contact to terminal board # 1 terminal . Feeding the indoor unit and ACIN1 on the control board .

The other hot ( terminal # 6 ) connects to terminal # 2 . Terminal #2 feeds the indoor unit and ACIN2 .

So , if Xinger has 240 VAC at the indoor unit , I would say the power relay is closing properly .

You all probably figured this out from the get go , but I am plodding along . :-)

All this is pretty much over my head . But I am guessing , sooner of latter , Xinger is going to have to figure out a way to safely and comfortably power up the system with 240 VAC . And follow the voltages ?

Please keep us in the peanut gallery updated . I for one , am learning a tiny bit from this thread . :-)

God bless
Wyr