I went to a new building with 38 heat pumps. every time the outdoor temp gets to zero or below, rooms can't keep up. The ewt at 1 unit was at 36 degrees. the manufacturer says at 35 degrees the unit will have only a 20 degree temp rise. This is not enough to heat outer rooms. I am waiting for info on the loops, but wondering why ewt is so cold. i think the loops are vertical, but don't know all info yet. Is this normal temps in cold climates?