Fixing Lack of Cold Water From Shower After Cartridge Replacement
Finding yourself suddenly without cold water in the shower after replacing a faulty cartridge can be frustrating. But don't worry - with a bit of troubleshooting, you can get your cold water flowing again.
Reasons for Loss of Cold Water
There are several possible reasons why you may have no cold shower water after changing out the cartridge:
- The replacement cartridge was installed upside down - Hot and cold water flows are reversed
- Cartridge not fully seated into valve body - Water flow is obstructed
- Debris buildup inside new cartridge - Blocks cold water flow
- Damaged or defective replacement cartridge
- Issues with hot and cold supply lines - Cold water supply disrupted
- Crossover in the plumbing system - Hot and cold water lines reversed
The specific cause will determine the steps needed to restore proper cold water flow to your shower.
Cartridge Installed Incorrectly
Many cartridge types are directional, with hot and cold water flowing in a specific orientation. If installed upside down, the hot and cold supplies will be reversed. You'll get all hot water when trying to access the cold.
Double check your installation instructions to ensure proper cartridge positioning. The cartridge may need to be rotated 180 degrees to align with the correct hot and cold water inlets.
Cartridge Not Fully Seated
If the replacement cartridge isn't fully seated into the valve body, water flow can be disrupted or blocked entirely. Over time, corrosion and mineral deposits can cause a cartridge to become lodged in the valve.
Use a cartridge puller tool to remove the stuck cartridge. Check for any debris or corrosion buildup inside the valve body. insert the new cartridge and firmly push it into the valve until it clicks fully into place.
Debris Inside Cartridge
Small pieces of sediment, mineral deposits, or corrosion can make their way into a replacement cartridge. This debris can obstruct water flow, particularly on the cold side.
Remove the cartridge and thoroughly flush it with water to dislodge any particles. Scrub debris from the inlet ports with a small brush. If flushing doesn't work, you may need to replace the clogged cartridge.
Damaged Cartridge
Sometimes a replacement cartridge is simply defective right out of the box. Issues like a broken pressure balance spool, misaligned ports, or cracked inlet valves will lead to improper water flow.
Test a suspect cartridge by running it under lightly flowing water. If flow is uneven, spurting, or all hot, the cartridge is likely damaged. Replace it with a new factory sealed cartridge.
Supply Line Problems
If the issue started immediately after a cartridge replacement, the likely cause is the cartridge itself. But a loss of cold water that develops later may indicate problems with the supply lines.
Examine the hot and cold supply valves and flex lines for cracks, leaks, or blockages. Turn the water on and off at the supply valves - listen for abnormal water hammer or uneven flow. Resolve any supply issues before reinstalling the cartridge.
Crossover Plumbing
In very old homes with galvanized plumbing, the hot and cold supply lines may have been crossed at some point. This reversal of flows means hot water enters the cold supply line.
Trace the hot and cold supply lines back from the valve to determine if a crossover has occurred. If so, the lines must be correctly aligned for the cartridge to function properly.
Diagnosing the Specific Cause
To fix the loss of cold water, you'll need to determine which of the potential causes is the culprit. We'll outline how to diagnose the issue step-by-step:
Check Cartridge Orientation
Verify that the replacement cartridge is oriented properly, with hot and cold water entering the correct inlets. Consult manufacturer instructions for the proper installation position.
If positioned incorrectly, rotate the cartridge 180 degrees to align the hot and cold water flows.
Ensure Cartridge Fully Seated
Remove the cartridge and examine for any debris or mineral deposits around the inlet ports and valve body. Clean any buildup with a small wire brush and mineral remover.
Reinsert the cartridge and push firmly until it clicks fully into place. Check that water flows properly when the supplies are turned back on.
Inspect for Debris Clogging
Take out the cartridge and thoroughly flush it with water. Use a small brush or pipe cleaner to scrub any dirt, sediment or debris from the inlet ports.
Reinstall the cartridge and turn on the water to see if cold water flow has been restored.
Test Cartridge for Damage
With the water supply off, run the cartridge under a light stream of water. Check that flow is even from the hot and cold inlets. If flow is reduced or all hot, the cartridge spool or valves are likely damaged.
Replace the defective cartridge with a new factory-sealed unit. Confirm proper cold water flow when water is turned back on.
Examine Supply Lines
Inspect the hot and cold supply lines for any leaks, cracks, or obstruction. Turn the supply valves on and off to check for odd sounds or uneven flow.
Make any necessary repairs to the supply valves and lines before reinstalling the cartridge.
Assess for Crossover Plumbing
Trace the hot and cold supply lines back from the valve to determine if they have been crossed at any point. Proper alignment is needed for the cartridge to deliver hot and cold water correctly.
If a crossover exists, rerouting of the supply lines is required to provide appropriate hot and cold flows.
Solutions For Restoring Cold Water
Once the specific cause of the cold water loss is identified, you can take steps to restore proper flow. Here are the solutions for each issue:
Reinstall Cartridge Correctly
If the cartridge is positioned incorrectly, remove it from the valve body and rotate it 180 degrees to match the hot and cold supply orientations.
Reset Cartridge Into Place
Use a cartridge puller to remove a stuck cartridge. Clean any mineral deposits or debris from the valve body before firmly reseating the cartridge.
Clean Out Debris in Cartridge
A clogged cartridge can be flushed with water and scrubbed with a brush to remove dirt and sediment. Reinstall after cleaning to test water flow.
Replace Damaged Cartridge
Swap out a defective cartridge with uneven water flow for a new replacement cartridge. Be sure to maintain the correct orientation when installing the new cartridge.
Repair Supply Line Problems
Fix any leaks or obstructions in the hot and cold supply lines. Consider replacing old galvanized supply tubing which is prone to flow issues.
Resolve Crossover Plumbing
Properly reroute crossed hot and cold supply lines so water flows match the cartridge inlets. Restore intended hot and cold alignment.
Preventing Loss of Cold Water
Take these steps when replacing a shower cartridge to avoid a recurrence of cold water loss:
- Review manufacturer instructions to ensure correct cartridge orientation
- Thoroughly clean valve body of any debris before installing
- Lubricate cartridge o-rings with silicone grease to avoid sticking
- Check cartridge operation by testing water flow before finishing
- Consider replacing galvanized supply tubing with PEX
- Use a cold water supply filter to keep debris out of line
- Plan to replace cartridges every 3-5 years to avoid age related issues
Losing cold shower water after a cartridge replacement is often just a simple installation oversight. With some focused troubleshooting and appropriate repairs, cold water flow can quickly be regained.
Paying close attention to proper orientation, ensuring the cartridge fully seats, and keeping supply lines in good working order will go a long way towards preventing the issue from cropping up again down the road.