Ductless mini-split indoor head relocation.
I’m pondering moving our 1:1 FS06 which is in a downstairs bedroom of our 1915 1600sq bungalow to just below the bedroom in a currently 1000 sq ft unfinished insulated (except the slab) basement . Adjacent to her room is a larger sized living and dining room with a KJ18 which has been essentially heating/cooling the entire house on its own. The reason for moving it is that we haven’t turned it on since it was installed mid summer. THe lowest temperature I’ve seen in her room was 64. (Although we haven’t experienced a polar vortex yet) She likes it cooler to sleep. Cooling the room was not an issue in the summer. I also believe it will get some stack effect into her room while keeping the first floors floor warmer. Current basement temperatures are 58 to 62° and I’ve moved my office down here. Plan to finish part of the basement in the future.
What is actual process of moving the indoor unit in terms of the refrigerant charge? Lineset would need to be shorten. Does refrigerant get wasted or can they system be sealed and “plugged back in.” See pic of where it would be moved to.
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Your installer will have two options regarding the change. One is to use the outdoor unit itself to "pump down" the refrigerant in the system into the outdoor unit, then valve off the outdoor unit at the service valves while the head is moved. Once the head is moved, the linesets (which are all connected--you can't isolate just the head being moved) need to be pressure-tested and evacuated. Then the refrigerant is released back into the system and any charge adjustments are made (if the linesets are shorter, you would typically be removing refrigerant). This is the quicker approach. The disadvantage is that you are missing an opportunity to weigh out the amount of refrigerant in the system to check for leakage.
The slower approach is to recover all the refrigerant into a clean recovery tank which has first been evacuated of air and moisture. The amount removed can be weighed. This process requires a refrigerant recovery machine. You are allowed to put recovered refrigerant back into the system from which it was removed, though some installers will prefer to use new refrigerant and send the removed material back for recycling. Because you need to evacuate the entire system (not just the linesets and indoor heads) the vacuum will take much longer.
Thanks Jon, that’s incredibly helpful.
One thing I you might need to consider is whether the move would require a longer lineset. If so, you may have a decision whether to add line to the existing set or start with a whole new lineset long enough to span the entire length. Once when I had a condenser moved my HVAC guy merely spliced in extra length using a connector. Of course, that connector ended up leaking. I suspect most of the time it is ok, but I also suspect that an unspliced lineset is a safer choice. I would be curious to hear from HVAC guys what they think.
Thanks Nick. Please see photo for reference. I’m actually shortening the line.