#2 Sanyo 24KHS72 AC/HP Install Project (Oct 2011) - Page 12

Xringer · 04-21-16, 01:04 PM

but it's oddly connected..

One side (the cold side) is wired to ground.
(The common chassis or neutral or center wire, of the 230vac hot wires).

The other side (hot side) is connected to HV via another device..
I think that device might be a thyrector diode or a TVS diode. Transient-voltage-suppression diode..

It's function is to short out overly high voltage, to ground via the fuse..

Puzzling, because the fuse should never see any current, unless the TVS conducts.

So, how could the controller diagnostics even know the fuse was blown?
I wish there was a circuit diagram for this board.. (CH2472)..

Xringer · 04-21-16, 01:22 PM

Well, that Z thing isn't the fuse.. I got around behind the unit and lifted up the lower right side and saw a big old fuse, sitting in a standard old fuse holder.. It's good..
The Z thing is HV protection of some sort. Most likely not the problem. ;(

WyrTwister · 04-21-16, 02:28 PM

Can you ask Sanyo technical support ?

God bless
Wyr

Xringer · 04-21-16, 03:14 PM

Quote:

Originally Posted by WyrTwister

Can you ask Sanyo technical support ?

God bless
Wyr

They sold out to Panasonic a few years ago..

I'm going to try running the outdoor unit in test mode..
Just to see if it can still turn over.

Edit:
The Test mode run didn't work. So, the problem is not in the indoor unit.
Not looking good right now. It seems like the main controller board has failed.
I'll have to see if it's even trying to boot up. Maybe in about 8 days,
when another day with 70F is forecast..

WyrTwister · 04-21-16, 05:28 PM

Is the board available ? At what price ?

We installed a Friedrich from Johnstone Supply , last year / spring . The main & only board went out on it in a snow / lightning storm , this last winter ( heat pump mode ) .

The price of the board was almost as much as the original sale price of the outdoor unit . Johnstone warranted it .

Praise the Lord ! :-)

I could see one component blown on that board .

Best of luck .

God bless
Wyr

Xringer · 04-21-16, 08:52 PM

They aren't cheap.. I see what might be one at:
https://www.encompassparts.com/item/...222/Controller

$535 seems like a pretty high price to pay for a PCB,
when I could install a 9,000 BTU in that room, for not much more..

WyrTwister · 04-22-16, 02:07 AM

Have you found a schematic for it ?

However you fix it or replace it , I suggest you install a surge suppressor on it . If it is not part of the unit . As a precaution .

Schematic on mine indicated it had a built in surge suppressor . I went ahead and installed a Sq D whole house surge suppressor at my service entrance loadcenter .

God bless
Wyr

Xringer · 04-22-16, 09:03 AM

I've looked for a schematic since I've owned these Sanyos.. Never found one.

The surge suppressor didn't help with this failure.
Eaton Complete Home Surge Protection-CHSPT2MICRO - The Home Depot
The two Protection LEDs are still on, so I guess it's not broken.

I'm starting to think about getting a new GREE Terra 9000 BTU and just replace that old Sanyo.
GREE Terra 9,000 BTU Ductless Mini Split AC FREE 25' Line Set

Right off, I'm not seeing the specs for cold weather operation..
I wonder how good these are, and the lower cost models.?.

WyrTwister · 04-22-16, 10:43 AM

Both of our MS's are HP;s , but I bought then mainly for A/C . I honestly do not know a lot about HP ratings .

It says HSPF (Heating Seasonal Performance Factor) 9.0 .

COP (Coefficient of Performance) 3.8

Does that mean anything to you ? I have no clue .

Says it is 27 SEER

For a 27 SEER unit , probably not a bad price .

Since it is an inverter drive unit & we live in a mostly dry climate ( the south west with summer time highs of 100 or above ) . I , personally would price a 12,000 BTU unit , also . Especially if I found a better deal on one .

My thought has been to try to purchase at low cost , in case of premature failure . To minimize the loss .

Also , check Amazon.com .

But I may be totally wrong .

Best of luck .

God bless
Wyr

Xringer · 04-22-16, 12:00 PM

Yeah, there is so much glass in the den, a 12,000 might be a better choice.
Especially during those really cold days in mid winter.

Saw this one: GREE Vireo 12,000 BTU Wall Mounted Ductless Mini Split Heat Pump System 208-230 VAC - Single Zone Systems - Ductless Mini Split Systems - Heating & Cooling
Seems like a better price than most and the 22 SEER seems good enough for the den..

04-21-16, 01:04 PM	#111
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	I think that Z is the fuse but it's oddly connected.. One side (the cold side) is wired to ground. (The common chassis or neutral or center wire, of the 230vac hot wires). The other side (hot side) is connected to HV via another device.. I think that device might be a thyrector diode or a TVS diode. Transient-voltage-suppression diode.. It's function is to short out overly high voltage, to ground via the fuse.. Puzzling, because the fuse should never see any current, unless the TVS conducts. So, how could the controller diagnostics even know the fuse was blown? I wish there was a circuit diagram for this board.. (CH2472).. __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

04-21-16, 01:22 PM	#112
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	Well, that Z thing isn't the fuse.. I got around behind the unit and lifted up the lower right side and saw a big old fuse, sitting in a standard old fuse holder.. It's good.. The Z thing is HV protection of some sort. Most likely not the problem. ;( __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

04-21-16, 08:52 PM	#116
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	They aren't cheap.. I see what might be one at: https://www.encompassparts.com/item/...222/Controller $535 seems like a pretty high price to pay for a PCB, when I could install a 9,000 BTU in that room, for not much more.. __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

04-22-16, 09:03 AM	#118
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	I've looked for a schematic since I've owned these Sanyos.. Never found one. The surge suppressor didn't help with this failure. Eaton Complete Home Surge Protection-CHSPT2MICRO - The Home Depot The two Protection LEDs are still on, so I guess it's not broken. I'm starting to think about getting a new GREE Terra 9000 BTU and just replace that old Sanyo. GREE Terra 9,000 BTU Ductless Mini Split AC FREE 25' Line Set Right off, I'm not seeing the specs for cold weather operation.. I wonder how good these are, and the lower cost models.?. __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

04-22-16, 12:00 PM	#120
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	Yeah, there is so much glass in the den, a 12,000 might be a better choice. Especially during those really cold days in mid winter. Saw this one: GREE Vireo 12,000 BTU Wall Mounted Ductless Mini Split Heat Pump System 208-230 VAC - Single Zone Systems - Ductless Mini Split Systems - Heating & Cooling Seems like a better price than most and the 22 SEER seems good enough for the den.. __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

04-21-16, 02:28 PM	#113
WyrTwister Master EcoRenovator Join Date: Jun 2013 Location: USA Posts: 543 Thanks: 6 Thanked 44 Times in 38 Posts	Can you ask Sanyo technical support ? God bless Wyr

04-21-16, 05:28 PM	#115
WyrTwister Master EcoRenovator Join Date: Jun 2013 Location: USA Posts: 543 Thanks: 6 Thanked 44 Times in 38 Posts	Is the board available ? At what price ? We installed a Friedrich from Johnstone Supply , last year / spring . The main & only board went out on it in a snow / lightning storm , this last winter ( heat pump mode ) . The price of the board was almost as much as the original sale price of the outdoor unit . Johnstone warranted it . Praise the Lord ! :-) I could see one component blown on that board . Best of luck . God bless Wyr

04-22-16, 02:07 AM	#117
WyrTwister Master EcoRenovator Join Date: Jun 2013 Location: USA Posts: 543 Thanks: 6 Thanked 44 Times in 38 Posts	Have you found a schematic for it ? However you fix it or replace it , I suggest you install a surge suppressor on it . If it is not part of the unit . As a precaution . Schematic on mine indicated it had a built in surge suppressor . I went ahead and installed a Sq D whole house surge suppressor at my service entrance loadcenter . God bless Wyr

04-22-16, 10:43 AM	#119
WyrTwister Master EcoRenovator Join Date: Jun 2013 Location: USA Posts: 543 Thanks: 6 Thanked 44 Times in 38 Posts	Both of our MS's are HP;s , but I bought then mainly for A/C . I honestly do not know a lot about HP ratings . It says HSPF (Heating Seasonal Performance Factor) 9.0 . COP (Coefficient of Performance) 3.8 Does that mean anything to you ? I have no clue . Says it is 27 SEER For a 27 SEER unit , probably not a bad price . Since it is an inverter drive unit & we live in a mostly dry climate ( the south west with summer time highs of 100 or above ) . I , personally would price a 12,000 BTU unit , also . Especially if I found a better deal on one . My thought has been to try to purchase at low cost , in case of premature failure . To minimize the loss . Also , check Amazon.com . But I may be totally wrong . Best of luck . God bless Wyr