Sanyo 24KHS72 AC/HP DIY install project

[Xringer]

I've seen that page before, and it seems strange they would have a limit that high,
and then tell you to use a minimum breaker of 20A.. Compressor Locked Rotor is only 17.5A..


At my current 124v line voltage, 248v is on the Sanyo..
248v X 22.5a = 5.58 kW.. That's more than twice the power on the name plate.

Maybe the 22.5 amp kick-out is what's going to happen during the worse case scenario..?.
(Notice the 22.5A limit is also on the 18,000 BTUh model.. I wonder why? It's max usage is less than 1600w).



230 X 10.8 = 2.484 kW.




"The quicker it gets back up, the sooner you can resume heating, so it seems logical this would be when the system uses a maximum amount of power."

That seems perfectly logical to the person that drives 75 MPH between red lights and stop signs.

IMHO, I think that the surge on my system is a bit over-done. I'm still very
suspicious that some firmware programmer decided that units going to
America had to have a Mega-Boost in high power mode & defrost exit mode.


Since the failed outdoor unit and the 'new' one were both made at the same time,
I also suspect the refrigerant charge, which I'm in the process of checking out.
I've done one heating measurement and plan to take the cooling measurement soon.
It would be great, if it turned out to be something that simple.


There is one reason that it may not be crappy firmware.
I've heard of a couple of other cases of power surges in Sanyo mini-splits,
but they were from smaller models than mine.
The owners of those systems also had to avoid calling for a larger than 2 degree increase in heat..

[S-F]

Originally Posted by Xringer

There is one reason that it may not be crappy firmware.
I've heard of a couple of other cases of power surges in Sanyo mini-splits,
but they were from smaller models than mine.
The owners of those systems also had to avoid calling for a larger than 2 degree increase in heat..

And the Sanyo owners aren't alone there. This is true of just about everyone with any kind of heat pump. The difference is that usually there is Aux heat which will kick in when a large demand is placed on the unit. The GSHP people say to set it and forget it. DOn't use a setback more than 2° or the bill will start to climb.

[Xringer]

No auto-backup heat here. Just me turning on a space heater or the oil burner.

I've been using 21C (69.8F) as our 24/7 setpoint and find it's pretty good.
We keep the master bedroom closed until about 9PM, so can get down to 65F in there.
But, by the time I get to bed, it's up a couple of degrees. Perfect sleeping temps.
By early morning, it creeps up to around 67-68 in there.

Today it was nice out (Partly sunny in the low 40s) while we worked in the Den.
It was chilly in there, so I moved the setpoint up to 23C (73.4).
That got the Den toasty in no time. Watched my Netflix in there too.
We are installing some new 'green' curtains in there. (Thermaweave??)
Sears: Online department store featuring appliances, tools, fitness equipment and more
Not too fancy, but they look nice.

[cholcombe]

Xringer, I'm taking the plunge and buying a Mitsubishi mr. slim heat pump this week I had an HVAC company out to give me an estimate. I'm thinking of getting the MUZ-FE12NA

I see that these put out 10.5 BTU/W which if I did my numbers right, could theoretically heat my house for half what it costs to run my oil heater. I love these ASHP's !

[Xringer]

NICE!! That's an impressive unit. I'm not sure that 12,000 BTUh would heat my house.
Too big and too many windows. How did you decided on that size?

10.5 BTU/W sounds great. What do you pay for kWh? I know that oil prices are up,
and I'm pretty sure they are going to trend upwards for many years to come.
I can't see oil ever getting very cheap again.

Those Mr. Slim prices are pretty high ($1665-$2000) compared to some brands,
I wonder what the installed cost is going to be..?.
It's a pretty simple one-day install (in many cases), if your pad is already in place,
they shouldn't ask for your first born..

[MN Renovator]

Xringer, is propane pricing on the same line as oil in your area? From people I know in the next next state over, Wisconsin, they say it is extremely expensive. I'm not sure how it compares to oil though because as far as I can tell, nobody in the midwest seems to use it, either because of the price or availability.

cholcombe, I'm also curious what the cost is professionally installed. The Mitsubishi units seem to be some of the best, I think Daikin are too but Daikin are priced like Trane HVAC equipment. If I remember on the specsheet the 12k BTU is a nominal rating and that it can ramp up from that point to, at least until the temperature is low enough to where its efficiency and output capability drops.

[Xringer]

I'm not sure about Propane, since we just use it for BBQing. Last fall is the last time
we filled up our little 20? pound tanks. We have used about 1/2 a tank over the winter.

I would guess that hiring an electrician to install a 230 line and someone to fab the pad
would be a lot of the cost of installing a mini-split. (Standard install, nothing convoluted).
If the home owner did that prep work, that should cut the labor cost a good bit..
The rest of the job isn't real labor intensive. Two guys could have installed mine in about 2 hours.
(Hanging the indoor unit, bolting down the outdoor unit and running the lineset).
It's likely a one-day install. But, if the vac job is done too quickly, that might be a problem for you later on..

Depending on outdoor temperatures, it could take a considerable time span to prep the installed system for startup.

[Vern2]

Love following this thread. Xringer, My exact thought (unit cost). I'm still thinking Sinco, Biggest mini split mader in the world, 3,000,000 units a year. Here is a 12,000 for $859.99Sinco.

The only things I've heard about Mitsubishi.
Customers: Very good unit.
Installers: Would rather install other type mini splits. Don't know why.

Making a pad, you can make one with 2 two-by-fours and a 5 gallon bucket, plus ready mix. Running the 220v line: I've been running all my 220 stuff with 1 1/4 plastic electric pipe, 4 #6 gage wires. Hooking up breaker, 2 wires. Neutral, ground to the ground bar, easy. Running pipe, drill holes, two screws for each bracket. Xringer has the mini split install for us.

Had a 2 ton split bid for garage, not mini. Duct work, for the plenum box and filter jack. This was one room 20'x 20'. $7,700.00, from Home Depot. You have to say the words. "I can do it!". I'm 66, had a stroke, can hardly walk and use of one arm. Yes, I do have a nice welding and machine shop. Link below with projects, shop stuff and video introduction.

The biggest problem is my wife, She says, it will take two much electricity, $$.

Okay tools $500.

[cholcombe]

I'm paying roughly .14-.16 cents per kwh when all is said and done. Maybe a little more. I'm just dividing my bill by kwh, not quoting that stupid 'price to produce' and transmit,etc. I think that's all just there to confuse you so you don't know what you're paying. Anyways.. rant over haha. I decided on that size because I'm trying to heat roughly half of the main living area. I roughly calculated that my oil boiler is burning 30,000 btu/h in the winter. So I figured 12,000 btu/h should make a decent dent in that. Plus you get the efficiency gain from not taking already heated air and blowing it up the chimney. I should get my quote back today and I'll let you know

[AC_Hacker]

Originally Posted by cholcombe

I should get my quote back today and I'll let you know.

The Mr Slim has a good reputation.

But you might also check out the 12,000 BTU Fujitsu Halcyon, it also has a good reputation.

HSPF = 12 (12 BTU/watt) a bit more than the Mr Slim.

Installation costs should be the same.

$1,556, includes shipping.

-AC_Hacker