Basically if your throat hurts it's the heat not the weed. Maybe if you had a long tube or through some water to cool the air.
--
as for it being safe....
It's not 100% clean like fresh air however IMHO it's not even half as bad for you as smoking pretty much anything else.
Consider the facts:
Pretty much nobody has died from cannabis and that's using combustion for all time until vapes were first used. Most of the people with lung cancer I would imagine smoke cigarettes anyway so the statistics could be due to other reasons, etc.
ok so if cannabis smoke doesn't cause fatality in comparison to smoking cigs or anything else really (crack)... then to me, going a step further to eliminate combustion, vaporizing sounds as you're preventing the plant matter (most of the bud) from going inside of your body in the form of a gas (particulate material suspended in a gas (air)). (solid matter in smoke as opposed to thin vapor of surface stuff)
Imagine breathing in this..
as opposed to breathing in the whole bud itself in plant matter form.... lol
imagine that nice ass bud and the result being a tiny bit of ash.... but the rest was inhaled into the lungs and breathed it back out with all it's natural parts all burned up in all it's glory of the plant...
now imagine avoiding all that and
breathing in the medicine that is secreted from the plant onto the surface....
which one seems better?
it's not 100% safe but if nobody dies from combustion then taking the surface stuff is way less harmful imo
(other factors include individual reactions to cannabis / pre-existing asthma or other conditions of course smoke and heat will irritate, etc)