Sanyo 24KHS72 AC/HP DIY install project

[st2288]

I have the same thought as Xringer, to use my Fujitsu to supplement my heating too. The way it looks now, I may able to save at least 50% of my heating cost.

[MN Renovator]

I've read the entire thread and it does look easy, the only part that I was thinking to get the help on was the vacuum/nitrogen/charge part at the end. I figured that having someone else do that part would save money on the vacuum gauge, pump, oil, etc. ...but if it really is cheaper to DIY the final step, I might just buy all the equipment.

I'm doing it more for the 25SEER air conditioning that the 12RLS provides but thought the heating part was a bonus because of my 1983 furnace that has no induction blower and 76% efficiency. The current air conditioner is a tired unit that is still working but I think was undersized(physically very small unit, tag is worn white so no info on it but probably a 1.5 or 2 ton unit, sits on a 20 amp 230v circuit) when it was installed(hotter summer days and the A/C will run non-stop and house will be 80 degrees) and probably an 8 SEER unit or whatever the minimum was in 1986 when it was manufactured.

So I see it as a cheap way to purchase a unit, install it and avoid all the markups and heavy installation costs of a tech to come in and do everything. It would be a system that would be undersized but when the need arises, I'd fire up the existing system until a level of comfort is reached and let the Fujitsu maintain it unless its too cold for the heat pump to run effectively.

[Xringer]

Originally Posted by st2288

Totally agree with Xringer. If you are handy and have some tools , you should be able to handle it. I put two in and couldn't believe what they want to charge without any power work.. Over $1000.00 with electrical, over $2000.00
Just take your time and read and read and read....

I have heard of a few guys who just wanted to get a licensed AC guy
in at the last minute, to test and release the R410a.
IIRC, the price was in the 100-300 buck range.

One of the reasons that I wanted to DIY with my own tools, was in case
there were leaks, and it ended up taking longer than expected to fix up.

My guess was, it would cost a little more to own the tools, on average.
But, you could sell them later, if you needed to.

I also figured that I might want to install more mini-splits at some later date.
Like a small 9k BTUh in my Master bedroom, or maybe in my daughter's house, or my Mom's place down in Texas..?.

[st2288]

You can never have too many tools... I figure if the a/c somehow develops a leak. I can service it myself.. If you look hard enough... you can get the pump, gauges less than 100.00

[Xringer]

I'm a lot more confident in the Sanyo staying in service this heating season..

We just had our line voltage lowered.!.

http://ecorenovator.org/forum/billia....html#post9722

So, things are looking up.. And, I expect to be using less power this winter.


Happy Holidays,
Rich

[AC_Hacker]

I'm not sure where the thread went, but there was some talk about the efficiency of the Inverter Technology being unique to mini-splits.

Well, now I have stumbled across this little jewel:

First Mitsubishi modulating ground source heat pump installation in Guernsey

System to be commissioned in two weeks time, the main controller, a Dataterm intelligent heating control will match the high efficiency of the Mitsubishi GSHP, making it the most efficient ground source heat pump package available in the world.

Thought you'd be interested.

-AC_Hacker

[Xringer]

Best in the world.. Humm, It looks VERY expensive! Way too expensive for about
90% of the US population.

But, if I know my DIYers, they will find a way to build or modify existing GSHPs
to use 'Inverter Technology'..

Which really isn't so technologically advanced. It wasn't pulled out of Hanger 19 at Roswell.

It's the same kind of transformer-less power supply that Japan has been building into their IT products for over 30 years,
coupled with transistorized speed controlled DC motor(s)..
And of course a little uCPU to make it work right.

http://www.ajmadison.com/ajmadison/i...ice_Manual.pdf
See page 133. It's an older model, but the PS is still about the same.

[MN Renovator]

Originally Posted by AC_Hacker

I'm not sure where the thread went, but there was some talk about the efficiency of the Inverter Technology being unique to mini-splits.

Nordyne has had their iQ drive for quite awhile. It uses an invertor with a Panasonic rotary compressor. It comes as either a 24.5SEER air conditioner or 22SEER heat pump with 10HSPF. It's the best SEER performance of any air-source air conditioner or heat pump that isn't a mini. These Nordyne units are very pricey though, likely the most expensive air conditioner on the market. The Fujitsu RLS series beats both of those measures and many inverter air source mini-splits meet/beat the 10HSPF for much less cash.

For non-invertors:
There is a 2.5 ton RHEEM/RUUD unit with a system-match(non 3rd party coil) that gets 10.20HSPF which might just be the best bang for the buck for a unit as far as heating goes for central HVAC.

There is also a York 3 ton with 17.5 SEER with 10.7HSPF capable of 34400 at 47 degrees F and 24800BTU at 17 degrees F. That seems like plenty of BTU for my needs for quite a bit of the winter if I were to time my heating out to the hottest part of the day it might not be too expensive to use this unit and it might be capable enough but I'm not sure if it would be cheaper than nat. gas though below the 110 therm bracket where I have .67/therm or cheaper.

I'd still rather get the mini and snag better A/C SEER since that is what I'm after. I wouldn't mind two Fujitsu 12RLS (25SEER/12HSPF) installed but one might be enough of a supplement if I implement it right for cost-effectiveness using the current central air(1.5 ton 8 or 10 SEER, I think) on the worst days to make up for the slack.

[cholcombe]

Xringer: Is there anything stopping you in the winter from pointing a few mirrors at the heat pump to increase the performance? I'm really looking into buying a unit like the sanyo you have after I saw your cost numbers you posted

[AC_Hacker]

Originally Posted by cholcombe

I'm really looking into buying a unit like the sanyo you have after I saw your cost numbers you posted

Technology is moving pretty fast for Mini-Splits. Do your homework.

If you live where cooling is the main issue, SEER ratings should be important to you.

If you live where heating is the main issue, SEER is not as important to you, instead you should look at HSPF ratings. (HSPF = Heating Seasonal Performance Factor).

In my experience many salesmen and sales sites don't seem to grasp this important distinction. Educate yourself.

-AC_Hacker