teevman - in answer to your second question - the various modes under cool setting work as follows:
1. AU causes the compressor to come on and the fan speed switches back and forth between hi and lo to satisfy the temp you set.
2. HI forces the use of hi fan speed only, with compressor on.
3. LO forces use of lo fan speed only, again with comp on.
4. HF uses hi speed A/C fan only, without compressor or furnace fan.
5. LF uses lo speed A/C fan only, again w/o comp or furnace fan.
Under the heat setting, it works the same, except BTU valve instead of compressor, and use of the furnace fan instead of the A/C fan. It's possible that you might not have all these modes, depending on model, but most units have them, as far as I know.
Hope this helps.
2003 Ford F-350 V-10 Crew Cab 4WD Long Bed
2004 Jayco Designer Medallion 29 RLTS 5th wheel
Bill, Gayle, and Mindi (dachshund)
Retired at last !
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