Will 1.5 HP Pump 80 Feet (Solar Heater)

[Poconos]

You should be OK. Remember that once the system is full of water you don't require any more pressure to circulate the water on the roof than with the heater on the ground. The suction on the downside equals the pressure needed on the upside. You need the push to get the water to the roof initially.
Al

[mas985]

Maximum head for that pump is a little over 50 ft so as long as the roof is lower than that, you should be ok.

[mscans]

Maximum head for that pump is a little over 50 ft so as long as the roof is lower than that, you should be ok.

Better install a vacuum break on the highest connection to allow the water to drain when the system is off. If not, when the pump is off the sun will heat the collectors while they are under vacuum and the collectors and piping can all be damaged.

If you live in one of the colder climes then the system must be drained anyway before the cold weather settles in.