Mitsubishi ducted units (PEAD, PVA, MVZ)
I’ve been considering having a Fujitsu Slim Duct system installed, and I decided to take a closer look at similar options from other manufacturers.
The following models from Mitsubishi were most interesting:
-PEAD (slim duct style, up to 0.6 static pressure)
-PVA/MVZ (traditional looking air handlers, up to 0.8 static pressure).
Are these Mitsubishi units generally well regarded? The principal advantage over the Fujitsu appears to be higher available static pressure (Fujitsu is 0.36 max). The principal disadvantages relative to Fujitsu seem to be (1) reduced modulating capability (PEAD and PVZ have minimum capacities around 9-10k BTUs on the nominal 24k air handler; Fujitsu is 3.1k minimum), and (2) at least for the PEAD and PVA, they do not maintain heating capacity as high at lower temperatures. Any other major differences that would be considered significant to an average residential consumer?
As for PVA air handler vs MVZ air handler, they seem pretty similar except that the MVZ is matched to a multi-head outdoor unit and therefore does not modulate the way that the PVA does. However, if matched to a hyper heat ODU, the MVZ maintains higher heat capacity down to lower temperatures. The PVA only has hyper heat capabilities when matched with the correct hyper heat ODU of at least 30k btu, but then its minimum modulating capability (in the 30k nominal unit) goes from ~10k to ~18k.
As for the PEAD “slim duct” style units, in addition to having lower available static pressure compared to PVA/MVZ (0.6 vs 0.8), the other major difference I notice is dehumidification capability. For a 24k PEAD matched with a PUZ ODU, data sheets show 6.9 pints per hour for a sensible heat ratio of 0.68. For a 24k PVA matched with the same PUZ air handler, data sheets show only 3.0 pints per hour for a sensible heat ratio of 0.83. PEADs also have a small advantage in efficiency.
Have I captured the major differences between these units? Other than static pressure and duct work concerns (and multi-split vs single split), is there any other consideration that would steer you towards a PEAD vs a PVA/MVZ?
Also, does anybody know if the PVA/MVZ air handler units are powered by the electrical connection from the ODU like a normal mini split? Or do the PVA/MVZ air handlers require separate electrical wiring and their own 240v breakers in the electrical panel? Looking at data sheets it looks like they receive power from the ODU like normal mini splits.
Thanks for any input.
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The PVA air handlers married to the PUZ "HA"xx compressors have pretty good low temp heating, but there is a limited range of HA sizes (2.5 tons through 3.5 tons, in half-ton increments), and the turn-down ratios are pretty limited too. Getting the sizing right matters quite a bit more with those than with Fujitsu xxRLFCD slim-duct units.
The smallest HA is the 2.5 tonner, with only a 1.9:1 turn down ratio, and 32K of output @ +5F:
http://meus1.mylinkdrive.com/files/PVA-A30AA7___PUZ-HA30NHA5_Product_Data_Sheet-en.pdf
By contrast, the 1.5 ton Fujitsu has an 8.25: 1 turn-down, and 21.6K of output @ +5F (+5F data from the NEEP spreadsheet):
http://www.fujitsugeneral.com/us/resources/pdf/support/downloads/submittal-sheets/18RLFCD.pdf
The HSPF 9.7 vs. HSPF 11.3 for the Fujitsu is enough to matter too. If you can get there (or almost there) with a Fujitsu 18RLFCD the Mitsubishi HA30 is going to be oversized, and probably won't hit it's already lower HSPF numbers.
The Mitsubishi MVZ airhandlers are powered from the outdoor units. No separate power is required.
Aun, if I remember from your previous posts, you don’t need the extra fan power...why go looking for it in the P-series?
Also, the P-series units are significantly more expensive.
John, good memory. On my second floor with the existing system, static pressure came back at 0.26, so that one should hopefully be fine for a Fujitsu.
On my first floor, though, static pressure is higher (actually closer to 0.8 with the existing system, but my contractor says he thinks it will be lower with a properly sized system, and he also thinks he can make some fairly easy tweaks to the ductwork and registers to lower it further). So I was looking at other potential options for that floor.
Also, I figured it was good to do my homework and just make sure I wasn't missing any obvious options :)
BTW, wow are you right about the P-series being more expensive. I won't be using online vendors b/c my contractor will be taking care of acquiring the system, but it looks like for a P-series the ODU + IDU alone are north of $5,000 -- whereas the Fujitsu is more in the $2-2.5k range. So if the Fujitsu installed by a competent contractor may be somewhere in the $8k range, I bet the Mitsubishi P-series would be closer to $11k or even more.
For comparison, I also had an estimate on a Trane XV18 heat pump (a standard ducted variable speed split system), and the estimate on that came in around $10,000.