How To Maintain and Repair Your Multiport Valve

There is nothing like enjoying a dip in the comfort of your own pool on a hot summer’s day. That being said, pool maintenance is crucial to make sure you can stay safe and cool all season long—especially when it comes to taking care of your multiport valve!

The multiport valve contains several valve ports that allow your pool’s water to move around so you can filter it, circulate it, and backwash it as needed.

With such a necessary component on the line, you probably need tips on how to repair your damaged or leaking multiport valve. Maybe you need advice on how to replace its various components.

Well, your search is over! We are here to give you all the information you need to maintain and repair your multiport valve in one easy, convenient place.

What to Do When Your Multiport Valve Is Leaking Around the Handle

You can fix this issue simply as long as your valve rotor is not damaged or cracked! If that is the case, you should replace the valve rotor or try using aqua fix-it. However, you need to do something different if your multiport valve is leaking around the handle and your valve rotor isn’t broken. In that case, it’s probably just because there is something stuck under the O-rings of your valve rotor, or they have gotten moved somehow.

To stop the leaking, clean the O-rings, making sure to apply silicone lubricant when you’re done to prevent them from cracking or drying out and adjust them back onto your valve rotor. If your O-rings are damaged or dry in any way, you can easily replace them for a few dollars by visiting your local pool store or hardware store.

What to Do When Your Multiport Valve Is Leaking Around the Corner

You should always check the pressure levels of your multiport valve if it is leaking around the cover.

If the pressure levels are above average, check your return lines for blockages and backwash your filter. If the pressure levels are low or average, then check your assembly O-ring. You can do this by unscrewing the whole multiport assembly from the part attached to your sand filter.

Chances are, your O-ring is probably dried out or damaged and will need to be fixed. Once you have disconnected your multiport assembly and inspected your O-ring, you will have to do one of two things. If the O-ring is broken or cracked, you will have to replace it.

However, if the O-ring is intact, remove it and clean the surface area it sits on to ensure there is no debris in the way. Then, wash the O-ring well and apply some silicone lubricant before reattaching it.

What to Do When the Body of the Multiport Valve Is Leaking

There are quite a few reasons that may cause your multiport valve body to leak, but, for the most part, they can all be easily fixed. Of course, make sure you thoroughly inspect your multiport valve body to determine if it is an internal or external issue. It is important to note that three ports make up the multiport valve body: the waste, the return, and the pump.

The return port may leak because the hot water from the pool heater can heat and shrink the PVC connector. Or the valve adaptor may cause leaking near the pipes if it is over-tightened. For the most part, all you will have to replace is the pipes and PVC fittings to stop these leaks.

It is cheaper to replace the valve body than it is to replace the entire valve, but your local hardware store should have whichever pieces you need to help stop the body of your multiport valve from leaking.

What to Do When Your Multiport Valve Is Leaking from the Waste Port

When you backwash the filter of your multiport valve, you will see water come out of the waste port. However, you should not continue to see water come out of the waste port after you are done backwashing. If that is the case, there may be some debris stuck between the spider gasket and rotor of your multiport valve. If this is so, you will need to flush out your multiport valve so the rotor can be repositioned onto the spider gasket.

To do this, you should shut the pump off and push the handle completely down, then turn the multiport valve slightly to the right and the left, and back into the filter position. After that, check the pump again by turning it back on. If your multiport valve is still leaking from the waste port, you should turn the pump off again and remove the cover screws so you can pull out the key assembly.

Check the spider gasket for damage. If it is loose, you can use silicone or super glue to attach the loose rubber to the valve body’s dry grooves. If the spider gasket has more damage on it than just loose rubber, you should replace it (see tips below). The spring inside of the key assembly may also be causing the waste port of your multiport valve to be leaking.

If you notice that there is not any tension when you push down on the valve handle or if it seems floppy, then the spring inside your key assembly has failed. This can happen over time due to chemical corrosion. You should check for rust under the lid of your key assembly near the spring.

It is important to remember that you should never try to stop leaking from a backwash line by gluing a valve on it. Doing this can cause water to bypass the filter, causing poor filtration and even worse problems if you forget to open the backwash line before backwashing.

Tips for Replacing Your Spider Gasket

As we have mentioned, the spider gasket is responsible for directing the flow of water in your multiport valve. To replace your spider gasket, use a small, sharp flathead screwdriver to scrape it out. Make sure you also scrape out any small bits of rubber the old spider gasket may leave behind. Make sure to clean the surface of the gasket groove well and let it dry completely before installing the new spider gasket.

Make sure you also get the right size of replacement gasket, as they can vary. With the flat side down, glue your new spider gasket in place, making sure to dab silicone or super glue in the dry grooves. Be sure that you only add the glue in a continuous line, without adding any to the sides, as this could cause overflow and leaking in the future. You should also take a moment to wipe off any overflowing glue.

Then, put the key assembly back over your spider gasket and tighten it in place. Turn the valve handle to the nearest setting (filter or rinse) and wait at least 24 hours to let the glue dry before using it again.

Tips for Replacing Your Key Seal Assembly

As we mentioned above, if water is leaking out of your waste port, you will have to repair or replace the key seal assembly. To replace the key seal assembly, remove the screws from the top of the key cover and handle assembly.

Tap out the pin that connects the key seal assembly to the handle. After that, remove the handle and valve cover. Take off the washers, C-ring, O-rings, and the spring. Apply silicone lubricant onto the O-rings and attach them to your new key seal assembly. Add the C-ring under the top O-ring and a washer onto the stem.

Then, add the spring and a second washer. Push the valve cover back onto the stem and add a plastic washer on top of the valve cover. Align the handle with the valve cover stem and push it in to compress the spring. After that, tap the handle pin back into place and align the valve body and cover assembly before screwing it back into place. You can also buy a pre-assembled key seal assembly!

Tips for Replacing Your Valve Spring

As we said, a broken valve spring may also cause your waste port to leak. If the handle of your multiport valve seems to be loose or floppy, the spring is probably damaged since it provides the tension that pushes down on the valve rotor to seal off your multiport valve’s compartments.

Just remove the pin to remove the valve handle and remove the key assembly from inside the multiport valve. Remove the cover of your key seal assembly and replace the spring and stem O-rings. Make sure you put the rotor and cover back in the same direction they were when you are reassembling everything.

Tips for Replacing Your Key Cover and Handle Assembly

If your valve spring is working fine and you are not having issues with your key assembly, you may have to replace your key cover and handle assembly to resolve the internal issues your multiport valve is experiencing. To do this, remove all the screws from the top of your handle assembly and key cover.

Make sure the inside is clean and clear from all debris before adding your new key cover and handle assembly, and that you apply silicone lubricant to your O-rings. Make sure you properly line up the key cover and handle assembly with the bottom of the valve, and press it on before tightening the screws back in place.

Tips for Replacing Your Complete Multiport Valve

If you have tried everything else and you seem to be experiencing a lot of internal problems with your multiport valve, or the valve body is cracked, you should just go ahead and replace the complete multiport valve. To do this, simply disconnect the plumbing and their fittings from your return and intake lines.

Then, remove the screws of the clamp holding the multiport valve in place and lift it off your filter. Before you reattach your new multiport valve, make sure you apply some silicone lubricant, and line it up with the standpipe inside your filter, and make sure your plumbing ports are lined up with your plumbing. After that, screw the clamp back onto the base of your new multiport valve and reattach your fittings and plumbing back onto your return and intake lines.

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Wrapping Up

No matter the issue you may be experiencing with your multiport valve, whether it is completely damaged or just leaking, there’s usually a common culprit that you can fix. If you need more help, make sure to call a professional (especially if you are replacing the whole unit). For more valve tips, head over to my main guide on pool valves.

Questions? Let me know.

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