20mm (3/4") Rubber Heater Hose

The 20mm (3/4") bore, RHS20mm, is the heater and coolant branch size on trucks, buses, marine engines and fixed plant, where the runs are long and a restriction at the hose costs cabin heat. It uses the same synthetic rubber tube and braided synthetic cord carcass as the smaller sizes, to SAE J20R3, rated 50 psi across -25 to +98°C. The 15.2 m box suits a fleet workshop that replaces heater lines regularly.

Key features

• 20mm (3/4") inside diameter
• Made to SAE J20R3
• Synthetic rubber tube, braided synthetic cord reinforcement
• Black smooth cover that stands up to weather and rubbing
• Working pressure 50 psi
• Temperature range -25 to +98°C
• Cut lengths from 1 m to 10 m, or a 15.2 m box

Applications

• Truck and bus cabin heater feed and return
• Marine engine coolant and calorifier branches
• Generator set and fixed plant coolant lines
• Long heater runs on motorhomes and coaches
• Coolant plumbing to auxiliary heaters and heat exchangers

Compatibility and fitting

• Sits over a 20 mm coolant spigot with a clamp each end; heavy duty worm drives are in hose clamps
• Support long runs with clips so the hose does not hang on the spigot and pull the joint open
• For steam and higher temperature service this is the wrong hose; see rubber steam hose

Does a longer run need a higher pressure rating?

No. The 50 psi rating is set by the hose wall, not the length. What a long run does need is support, because an unsupported 20 mm hose full of coolant is heavy enough to work the clamp loose over time.

Dispatched from our Brisbane warehouse. Australia-wide delivery, or collect from the warehouse once your order is confirmed ready.