Mini Split System Critique
Looking for some opinions on this system design – specifically how to figure out if it would be oversized based on the turndown ratio of the system. It looks like with the 4 heads minimum cooling will be 17,040 BTU and heating 15,900 BTU.
Id love to hire a consultant to advise on this if anyone can recommend one. But I’ll also take any free advice anyone is willing to give.
Note that in the Manual J all the numbers from the PDF have to be divided in half as the calculations were done for 2 identical apartments combined.,
Actual Manual J –
Total heating required: 31,164BTU
Total Sensible Gain 16,929 BTU
Latent Gain 3,699
Total Cooling Required 20,629
Marlborough, MA
Outdoor Unit is LG LMU300HHV
Indoor is ducted LDN127HV4 and LMN079HVT
Can anyone recommend a better low ambient temp heating multi head mini split with better turndown ratio for 3/4 heads?
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Replies
I don't think that will work well on a single 4 zone unit.
If you must have the wall mounts in the bedrooms, your best bet is to put the living ducted unit and the main suite unit on a LMU180HHV and the other two bedrooms on another two zone unit. This way the most used zones will be on a single unit, this combined load should be enough to keep the outdoor unit from cycling too much.
The best setup (most likely cheapest as well) is to ditch the wall mounts and duct the whole place.