Can I replace just 1 section of drain line-Culligan softener

The drain line from the control valve to drain (not the brine line between the control valve and salt tank) is only under pressure during regeneration.

The entire drain line is the same age. Unless there is a reason not to, I'd replace the entire drain line and avoid a repeat of this problem.

Re: Can I replace just 1 section of drain line-Culligan soft

Yes you can replace a section with two insert couplers for the size tubing they used, or use one coupler at the spot of the split depending how long it is. the size is printed on the tubing every 2 feet roughly and it usually is IRS (iron pipe size) not CTS (copper tubing size) which is smaller ID than IPS.

There is no pressure in a drain line unless there is some type of blockage. And you don't want any blockage in a drain line.

There is a build up of line pressure if the run is too long. . .
Make sure the pipe is large enough in diameter and that you have an air-gap.

Water pressure is caused by resistance to the flow of water.

All drain lines are open discharge, meaning the far end of the line has nothing on it to prevent full flow out of it; the end of the tubing or pipe is wide open.

Any resistance caused by friction of the water flow and the inside wall of the tubing or pipe OR elbows or other fittings, causes a pressure loss, not an increase. Friction is a resistance to flow, but in 100' of tubing or pipe it is all but immeasurable.

All softeners and backwashed or regenerated filters have a DLFC (drain line flow control) rated in gpm. The gpm is dictated by the volume and type of resin or mineral/media in the softener or filter. All DLFCs are rated in tenths of a gallon.

To overcome a decreased flow rate gpm (that REDUCES the flow rate gpm which causes failure of the resin/mineral/media in the softener or filter) caused by increased friction loss in a smaller ID drain line than required due to the length of the drain line, you increase the ID of the drain line OR increase the DLFC gpm; by x tenths of a gallon.

Re: Can I replace just 1 section of drain line-Culligan soft


I agree, if you can change the whole line, do it. It is not that expensive and will eliminate the resistance due to scale build up. I have seen a lot of Culligan drain lines that were very thin and tended to kink and crack.

You may have a 1/2" drain line. If it extends more than 40-50 ft, increase the size to 3/4". The water in the drain line has resistance as it passes through the lines and the flow slows. This slowing of the water builds backpressure. If your line elevates, this increases the pressure loss. Every elbow, loop or other changes in a straight line adds to the resistence.

Resistence is measurable even in short distances and charts and guidelines are provided as an easy access to determine how much resistence exists in a given situation.

Not providing adequate flow may cause the resins not to lift properly and your regenration cycle can suffer. Couplers I have seen for thin hoses fit inside the hose, thus further reducing inside diameter and flow rate. Go ahead and replace the whole hose/pipe if you can.

Andy Christensen, CWS-II

That's what I'm talking about Andy, I'm not sure what Slusser is going on about though :wink: