HVAC Brand Opinions
- Thread starter tmbrown97
- Start date
CharlieWayne
Member
Lou Apo said:
The Mitsu ducted air handlers are not direct replacements for traditional air handlers but can be used for individual zoning if you redo your duct work. I guess each system has its own application and also would be dictated by each jobs scope of work. Some may elect to do a full redo the entire system, while others might do a simple retro where changing just the air handler makes since with a conventional like model.
Lou, You have made some good comments here and I thank you for your input from your experiences. So far I have not done all the research needed but have a base idea on what my home needs. Looking into what you said above I now know there is a difference between the mini splits with variable compressors and the full VRF systems. While I'm not sure the full extent of the differences other than maybe to the ability to heat or cool at the same time.
Like Work2Play had mentioned, my home is 20 years old and also has outdated windows and other sources of heat gain. First and foremost I need a proper Manual J by a independent HVAC Engineer so that I can locate all the sources of Heat Gain (live in FL a cooling dominated climate). Some upgrades have been done so far and comfort differences have been noticed but I still have to much heat gain or lack the ability to move this heat back outside.
In my application our home is 4,200 Sqft. After the original build of 3,300 sqft FL ranch home, a two story addition was built on the back side and the contractor left in place the existing concrete block wall. They installed a traditional 2 Ton heat pump for the 1,000 sqft addition, but note that this addition has 15 windows that are double pane but lack energy standards of today. On the front side of our home (3,300 sqft) we have a 4 ton unit that runs for hours just to pull the temp down a couple degrees which is obviously undersized. We inherited all this when we purchased the home. The 4 Ton unit was installed in 2008 and the 2 Ton was installed in 1997.
With looking at these Mini Splits and the zoning capability, I feel a zoned mini split system would be much the best choice not only for energy efficiency but also ease of install. Due to the block wall, 1/4" & 3/8" cooper lines would be so much easier to bring through this wall to add HVAC tonnage to the main house if the older 2 ton unit were replaced with a new 4-5 ton mini split.
Right now my main intent is to gather ideas and soon I will enlist a non biased professional HVAC Engineer that will perform the Load calculations but not have anything to do with the purchase, sale, or install of equipment. I'm sure once the load calc comes back then we will look at renos or upgrades to reduce the heat gain which thus will reduce our need for over sized equipment.
This is an excellent topic and thanks to all for contributing.
CharlieWayne
Member
Here's a link of a system that's used to integrate LG's VRF into home automation systems.
Personally I run HomeSeer Pro and haven't looked into how this specific hardware could be intregrated but wanted to share that there are manufacturers designing solutions for people like us.
http://www.coolautomation.com/products/coolmaster_es/coolmaster-6000l-lg-vrf/
Personally I run HomeSeer Pro and haven't looked into how this specific hardware could be intregrated but wanted to share that there are manufacturers designing solutions for people like us.
http://www.coolautomation.com/products/coolmaster_es/coolmaster-6000l-lg-vrf/
apostolakisl
Senior Member
CharlieWayne said:
For what it's worth, I have a friend who is an hvac installer who does mini-splits a lot. He loves them. He thinks Mitsubishi are the best, is happy with Fujitisu, but curses LG. That's just one guy's opinion, so take it as you will.
The Mitsubishi full size VRF air handlers are dimensionally the same as a traditional air handler and the ducting is done in the same basic fashion. I have personally toured the mechanical area of one of these systems and seen it all and reviewed it with the Mitsubishi rep. The minisplit air handlers are quite obviously different. I have never personally seen the mini-split air handlers installed, only watched one on TV, for whatever that is worth.
The VRF units come in much larger sizes. So you can do one outdoor unit for as much as 30 tons. The VRF units have more options and can do water heating/chilling and stuff like that. But for a residential application, you get most all of the benefits of VRF in a mini-split at small fraction of the price.
apostolakisl
Senior Member
Work2Play said:
Well I guess you need more than 5 tons. 5 tons would probably be enough in a tight well insulated house of 4000 sf even in your heat. I have 8 tons in 6000 sf which would translate to 6 tons in 4000sf. My unit does not struggle at all and even on hot days mostly still runs in stage 1. The manual J figured I needed at min 6 tons for my house, but I went with more counting on the 2 stage units to still not cycle on cooler days .. . and it indeed does not cycle.
Perhaps you do 2 3 ton units with 2 air handlers each? If you only plan on living there a few more years, just put a regular system in though. Probably need 2 units and zone it just using the 2 units.
apostolakisl
Senior Member
d.dennerline said:
Your comment struck me because I thought for sure you needed an epa license for r410a. In fact, you don't need one to buy it, but you do need one to handle it. Go figure. So technically you would only be breaking the law when you got home and charged your system. But as it turns out, many supply houses won't sell it to you without a license (true of the local place I get my stuff).