Bringing this back up again, the last two summer have been mild here, not many 90 degree days, which is when this unit struggles to keep up. We have had several days of 90 degree plus. Good news is I found a way to stay comfortable upstairs: manually shut the downstairs ducts off. Unit does ok if I do that but of course it just gets too hot downstairs. Water furnace, back to you for help. Looks like my contractor is out of business, he is working for another local firm. Who can help me now?