Weil McLain 590-317-650 Silicone Tube
The Weil McLain 590-317-650 Silicone Tube is a 17 in. length of red silicone tubing with a 1/8 in. inside diameter and a 1/16 in. wall. The catalog designation reads "Tube Sili 1/8 in. ID x 1/16 in. x 17 in. Red," and distributors list it as a red silicone tube of the same size. It is a flexible, heat-tolerant silicone line supplied cut to length, so you can fit it to a barb without trimming a long roll.
Silicone tubing is used for low-pressure sense and vent lines because it stays flexible across a wide temperature range and slips over a barb with a snug, sealing fit. Unlike a vinyl line, silicone does not harden and crack quickly near warm components. The Weil-McLain 590-317 series includes several silicone tubes, among them the 590-317-630, 590-317-631, 590-317-632, 590-317-645 and 590-317-647, so match the length and inside diameter to your original line before you order.
When you replace a silicone line, trace the full run first. Look for a line that has been pinched, kinked, split at the barb or filled with condensate, because a restricted sense line can cause nuisance pressure switch lockouts. Push the new line fully onto each barb, and route it with a slight downward slope or a drip loop so water cannot sit in a low spot. Do not stretch the line tight around a corner. Check each connection by hand after the boiler has run, since silicone can relax slightly after the first heat cycle. A fresh line at every control replacement is an inexpensive way to avoid a repeat visit. Confirm compatibility with your equipment before you order.
Key Benefits
- Red Silicone Construction: Stays flexible and seals on a barb across a wide temperature range.
- 1/8 In. ID x 17 In.: Cut to length, so you do not need to trim a long roll.
- 1/16 In. Wall: A wall thick enough to resist collapse on a low-pressure line.
- Part of the 590-317 Silicone Series: Related to the 590-317-630, 590-317-631 and 590-317-632 tubes, which differ in size.
Common Questions
- What size is the 590-317-650? 1/8 in. inside diameter, 1/16 in. wall, 17 in. long, in red silicone.
- Is it the same as the 590-317-630? They are different numbers. Match the length and inside diameter to your original line.
- Why replace a sense line? A pinched, cracked or water-filled line can cause nuisance pressure switch lockouts. A fresh line removes that variable.