It sounds like you're off to a good start, but I'll throw my in.
Read HVAC-Talk every day.
Be on time.
Be a student of the trade. Learn not just how, but why.
Wear kneepads, even for the standing up jobs.
Buy quality tools and quality boots.
Don't kiss @zz and don't ever hang your co-workers out to dry. Always take the high road. If there is an issue in the field, resolve it in the field with reason and discussion between yourselves as adults.
Always pass tools handle first
Think about if you were the one working what would you need from a helper next?
Dont stare like a trout at your journeymen
If the workplace is getting messy or untidy you need to ask yourself why thats happening
Show up on time, don't lolligag (walk at a good speed, don't just amble along), don't check your personal phone every 15 seconds. If your journeymen looks like he is trying to work something out, don't ask him a million questions. If you are doing an install, think a couple steps ahead. Have the tools ready to go for when they need to be used.
Did I mention not being late to jobs? Oh yah, don't be late to jobs.
ABSOLUTELY SPOT-ON. Just fired someone for not being on time...
All listed above is great advice. Also in slow times take Time to clean the shop, organize the truck. Rain days are also a good time to build a few plenums and use the black iron scrap to make various length pipe nipples to speed up installs. It uses up the scrap and gives you practice with the equipment.
Anticipate what tools or piece of material the person you're with will need and have it ready them. Aside from that, show that you give a crap and want to improve yourself. Put together an education plan and stick with it, even if it's just reading operations or service manuals, and reread your text books.
If the person you're working with is doing something that you've read to be a bad habit, suggest the correct alternative and if he tells you off just keep your mouth shut and wait until you get some time in before you try and "change the world".
You're 19, don't worry about being perfect. Just show up on time, do what's asked, look hungry to learn and keep improving. Also, I'm tired of hearing the generation that raised us ***** about how much we suck, so don't screw this up
It is the number one trait that is wanted by NASA for new astronauts. Here's their definition from a 1960's application guide.
"The quality most needed by a scientist serving as an astronaut by the single word 'perspicacity'. The task requires an exceptionally astute and imaginative observer but also one who's observations are accurate and impartial. He must, from among the thousands of things he observes, quickly pick out those that are significant, spot the anomalies and investigate them. He must discriminate fine detail and subtle differences in unfamiliar situations, synthesize observations to gain insight into a general pattern, and select and devise key observations to test working hypotheses. He must have the good judgment to know when to to stop a particular set of observations and start another.
The scientist as an astronaut must translate observations into verbal form and be able to generalize from observations to derive appropriate conclusions."
It's a lot, but people who have been in this business know EXACTLY what this is talking about. Perspicacity. Have it. Try to think what the journeyman is thinking and anticipate his next move. THAT will make you a better apprentice, and ultimately an excellent journeyman.
I also work by 2 simple rules, that are not so simple for so many people it's unbelievable.
Showing up on time is important but showing up every day is even more important.
Having someone show up on time 9/10 days and calling in sick one day out of 2 weeks is absolutely useless to me if I can't depend on them.
When you are asked to go get A, B, and C. Don't come back with only A. Forgetting B, and C.
Keep your personal life personal and on your own time as much as possible. In other words keep off the damned phone texting and talking while on the job.
Check your texts or emails during your breaks or lunch.
Your friends may not be working at your age and may not understand responsibility so ask them not to text you during work hours as much as possible.
This will prevent technicians like myself from asking you to leave your phone in the truck if it becomes a distraction.
Be dedicated to your trade.
Purchase quality tools.
Make a plan so that you put a little money aside every week towards your tools so that you will always be well equipped.
Your trade will reward you greatly over your lifetime.
Keep the work area clean and neat.
Be observant, there are times when more time can be taken to do a job and there are times when you must work quickly for one reason or another.
Ask questions when you don't understand something if it is the right time. If the tech doesn't have the time to answer the question at the time make a note of it so you can ask the question on the way to the next call.
Don't let yourself be used as a slave to the tech. Let them know you want to learn to improve and move forward.
I saved the best advice for last.
Spend as much free time as possible on this site.
You can learn a lot just browsing these forums.
Checkout both the wall of pride and wall of shame forums for how jobs should or shouldn't be done.
Checkout the tool forum for what you should or shouldn't purchase.
Post questions if your tech can't provide you with an answer you feel is satisfactory.