I would say personally, tubing benders. Saves time and fittings.
Would have to say my digital manifold. Many different points read and combined on screen. Makes start ups and repairs requiring charging so much more accurate.
Dupont Refrigerants makes a (FREE) pressure - temperature calculator app. for your smart phone. Choose the refrigerant, then this app. will calculate subcool, superheat or convert temp to psi and visa versa. very easy to use in the field.
By far digital gauges. Digital gauges take a lot of guess work out of old school calculations. They register high on time saving and are very good for our industry.
For equipment, my Fieldpiece SC260 and my JB gauge set, both for their accuracy and easy use. For making duct work my But Scratcher and unit-shears.
My brain, reading and keeping up to date on new technology, an listen to old HVAC guys sharing war stories at the supply house. Learning from the mistakes of those who were there before me. Last, always, always, remember you own all the previous problems, when you walk away.
definitely 100% has to be my propress. When you can cut hours off a boiler installation, or days off a house renovation, there’s no question that’s the best time saving tool.
My companies most favorite, time saving tool in the HVAC business is the software, Picture Perfect Pricing. With this software, tech place into system service that is needed and the software makes a Picture Perfect Price as well as a Picture Perfect layout for the customer to understand services needed and services recommend as well as service contacts. Best thing I ever invested into my business.
Testo digital manifold gauges.