Mitsui AC unit possible miss match?

I have had installed 4 Mitsui AC units. The 2 x 12 units work fine cooling the rooms quickly but the 18 and the 24 are having issues and are currently being investigated.
The 24 unit outside is MVE XO 24 HL4 and has been married to an inside unit MVE XI 18 HL4. Surely both should be 24 spec? The installers have said the 18 and 24 inside unit are the same but I'm not really convinced.
I'm unable to see the 18 units external serial number as its located too far away.
Thanks for any help
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wrote:

manufacturer's recommendation...
What is your real problem? People in the US doing what the rest of the world has been doing for decades, without your assistance?
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<default> wrote in message

I have no problem but apparently you do!!! #1 if your condenser is over size you have condition where Evaporator will freeze up! and needless to say sweating of registrars water drip? #2 If you condenser is undersized compare Evaporator then you dew pint will be so high that no Humidity will be remove and less cooling, either way it will be uncomfortable!! So if is going to work yes but how???
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If its a heat pump, then your really going to be screwed... undersized evap will cause the system to shut down on safeties in heat mode
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wrote:

Get real! Evaporators sweat - fact of life. You're trying to say that the orifice of the evap valve somehow renders the whole evap useless. Hardly. It is only a little more efficient - pressures didn't change the whole length of the evap should be boiling fluid for the highest efficiency. At worst case, you may have paid for more evap tubing than the system can use.

Look, I don't like it any more than you - but technology develops with time. We are all becoming obsolete - I know I've seen it in electronics - nowadays a degree is near useless for something like analog electronics - programs can do that better than the young engineers of today. That's life. Now a day so called engineers are learning to run before they learn to stand - let alone run (in electronics) They design whole systems with logic, and no or little understanding of the physical laws they are using.
Newspapers? With real paper?
I'm sure the best buggy whip manufacturer had the same lamentation.
People, ultimately, will be useless (or for all practical purposes, save the top geeks) That's the way we designed the world to work, and it is doing what it was designed to do.
Adapt, retire or perish. Them's the choices.
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Wrong, as long as you have the proper orifice or expansion valve for the compressor capacity along with the proper airflow it is fine, the problem with an undersized evap is that at the necessary airflow the velocity will be so high it slings water off of the coils instead of it draining into the pan.
It is fairly common practice to oversize the evap by 1/2 ton to reduce the static pressure drop across it and increase surface area for better dehumidification. It doesn't matter if the evap is the size of a Sherman tank as long as it has the necessary 350-400 CFM per ton of air flowing through it.
A 1/2 ton oversized minisplit indoor unit is a good thing, as long as it has a TXV and a multispeed or variable speed fan, when it is hot inside you can run it on high and increase the sensible heat removal at the expense of latent to get the temp down then turn down the fan speed to get out the latent load.
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The problem is that the evap coil is 25% undersized.... in heat mode, the system is going to shut down on high pressure safetys. Inless its a high end mini-split, its not going to have a TXV, or VFD to compensate. What he has done is the equivelant of pitting a 3 ton evap on a 4 ton condenser. That dog won't hunt,
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but you would not touch mine if you was last person in the state You are unbelievable I would not even comment on your post!!!!
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