Johnstone Supply

Johnstone Supply is an HVAC/R Wholesale Distributor with equipment, parts, supplies, and services for Contractors.

[Johnstone Supply @js_HVAC]

🎃 The pumpkins are ready, and now it’s your turn!

Stop by Johnstone Supply – Wilmington to check out the pumpkins decorated by our team and vote for your favorite. Bring your coworkers and cast your vote before voting closes Friday, October 9, at 5:00 p.m.!

We can’t wait to...

[Johnstone Supply @js_HVAC]

Join us for Innovair Counter Day at Johnstone Supply Wilmington!

📅 September 24, 2026
⏰ 8:30–11:00 AM
📍 315 Marlboro Street, Wilmington

Explore the latest Innovair products, see hands-on demonstrations, and enjoy refreshments from Middle of the Island Catering.

Attend...

[Johnstone Supply @js_HVAC]

Innovair has arrived at Johnstone Supply Wilmington!

Explore a new lineup of residential and light-commercial HVAC equipment, including inverter systems, side-discharge units, package heat pumps, and mini-split options—all at competitive prices.

Stop by or contact our team...

[Johnstone Supply @js_HVAC]

It's the last week of the Johnstone HVAC Insight Challenge. Don't forget to tune into the HVAC Nationals broadcast next Friday, December 13, on CBS Sports Network.

What is the typical temperature range for superheat in a properly functioning air conditioning system?

[Johnstone Supply @js_HVAC]

Week 12 of our Johnstone HVAC Insight Challenge is here. Think you’ve got what it takes to be the next HVAC national champion?

Which component in an air conditioner removes the heat from the refrigerant and expels it outside?

[Johnstone Supply @js_HVAC]

It's week 11 of our Johnstone HVAC Insight Challenge. Think you’ve got what it takes to be the next HVAC national champion?

What is the main function of the reversing valve in a heat pump system?

[Johnstone Supply @js_HVAC]

Week 10 of our Johnstone HVAC Insight Challenge is here. Think you’ve got what it takes to be the next HVAC national champion? Answer the poll on for a chance to win.

What technique can be used to make a good flare on copper tubing?

[Johnstone Supply @js_HVAC]

It's week 9 of our Johnstone HVAC Insight Challenge.

When under a deep vacuum, a hermetic refrigeration compressor's...
A. Keep oil warm to prevent breakdown.
B. Insulation boosts dielectric strength.
C. De-energize crankcase heater.
D. Energizing may damage windings.

[Johnstone Supply @js_HVAC]

Week 8 of our Johnstone HVAC Insight Challenge is here. Think you’ve got what it takes to be the next HVAC national champion?

When is using a bubble solution leak detection more appropriate than using an electronic leak detector?

[Johnstone Supply @js_HVAC]

It's week 7 of our Johnstone HVAC Insight Challenge. Think you’ve got what it takes to be the next HVAC national champion? Past questions are open through the end of the challenge.

What is the primary reason for pulling a deep vacuum on a refrigeration system?

[Johnstone Supply @js_HVAC]

Week 6 of our Johnstone HVAC Insight Challenge is here. Think you’ve got what it takes to be the next HVAC national champion? Past questions are open through the end of the challenge.

Where should the liquid line filter drier be located?

[Johnstone Supply @js_HVAC]

It's week 5 of our Johnstone HVAC Insight Challenge. Think you’ve got what it takes to be the next HVAC national champion? Answer the poll for a chance to win.

What is the purpose of using flux when soldering?

[Johnstone Supply @js_HVAC]

Week 4 of our Johnstone HVAC Insight Challenge is here. Think you’ve got what it takes to be the next HVAC national champion? Answer the poll for a chance to win.

What is the benefit of using helium as a trace gas with nitrogen for pressure testing?

[Johnstone Supply @js_HVAC]

It's week 3 of our Johnstone HVAC Insight Challenge. Think you’ve got what it takes to be the next HVAC national champion?

When performing a leak detection, the movement of the leak detector around the refrigerant line should be at least...what?

[Johnstone Supply @js_HVAC]

Week 2 of the Johnstone HVAC Insight Challenge is here. Think you’ve got what it takes to be the next HVAC national champion? Past questions are open through the end of the challenge.

What is the importance of nitrogen gas flowing in the pipe/tubing during brazing?

[Johnstone Supply @js_HVAC]

You had us at Milwaukee! Follow us and join us every Friday to answer the HVAC Insight Challenge questions. The top responder will win the impressive Milwaukee 4-Piece Cordless Combo. Top participants will also receive a unique discount code as a congratulations. Week one up now.

[Johnstone Supply @js_HVAC]

It’s week 1 of our Johnstone HVAC Insight Challenge! Think you’ve got what it takes to be the next HVAC national champion? Stay tuned for our prize giveaway announcement later today.

What tool should be used to tighten the joints and fittings in split systems?

[Johnstone Supply @js_HVAC]

Can you believe 80% of the contestants shop at Johnstone Supply? Meet our HVAC National Championship Pro finalists for 2024: Alex Ivey, Craig Childress, Curtis Harrington, Dagner Espinosa, Jerrad Porter, Joe Rittorno, Nathan Richards, and Shawn Price. Go get ‘em!

[Johnstone Supply @js_HVAC]

Think you got what it takes to be the next HVAC National Champion? Test your skills over the next 13 weeks. We’ve partnered with @NATEtechnicians to bring you the Johnstone HVAC Insight Challenge. Think you’ve got what it takes? Stay tuned for our Milwaukee prize giveaway.

[Johnstone Supply @js_HVAC]

Our friends at @YokohamaTC and @HvacNationals are giving away a FREE set of tires for a vehicle in your fleet. Rally your colleagues, submit and you could win! Enter now at https://t.co/t1t7Mroxsd and include your company name when you take the challenge!