Backwash Valves

Backwash Valves

Visual Explanation of a D.E. Filter with a Push-Pull Valve on  Filter Position

DE Filter Push/Pull Valve (Backwash) Position: When the push/pull handle is in the up position, the filter reverses the flow allowing the dirty water to go out the waste line or backwash hose.

DE Filter Push/Pull Valve (Filter) Position: When the push/pull handle is in the down position the filter is filtering the water and returning it to the pool.

Visual Explanation of a Sand Filter with  a Push-Pull Valve in  Backwash Position

SAND Filter Push/Pull Valve (Backwash) Position: When the push/pull handle is in the down position the filter reverses the flow through the filter sending the dirt to the waste line or backwash hose.

SAND Filter Push/Pull Valve (Filter) Position: When the push/pull handle is in the up position the filter is filtering the water and returning it to the pool.

Types of Backwash Valves
PUSH-PULL VALVES

The push-pull valve, also called slide valves, mounts on to bulkhead fittings on the side of a Sand or D.E. filter. The advantages of a Push-Pull valve are that they are simple to use, simple Example of a  Push-Pull Valveto understand, have very few parts, and are less restrictive to water flow than the multi-port valve.

Push-Pull Valves use a plunger with two disks (see diagram above). The only action is to either pull the handle up, or push the handle down. Sand filters usually operate in filter mode with the plunger in the up position, and backwash by pushing the handle down (always shut off pump before changing a backwash valve). D.E. filters are usually in filter mode when the plunger is down, and backwash by pulling up on the handle.

When you pull up or push down on the plunger of a push pull valve, you are reversing the direction of water into and out of the filter. (which is where we get the word “back-wash”).

How Long do I backwash my filter for?

Backwash until the water runs clear out the waste line. Usually about 2 – 3 minutes. You may need to add water to the pool before or after backwashing. On a D.E. filter, the last step is to add the fresh D.E. powder to the filter, through the skimmer.

When do I need to Backwash?

When the pressure gauge indicates a pressure rise of 8 – 10 lbs above the clean, or start-up pressure.

What Maintenance do I need to do for my Slide Valve?

Lubricate the valve o-rings at least once per year. Remove the plunger from the valve body and apply a Teflon based lubricant like Magic Lube.

Help! My Slide Valve leaks out the waste line all the time!?!

You most likely have “blown a gasket”. Remove the plunger from the valve body and inspect for broken or missing disc o-rings.

Multiport Valves

The multiport valve, also called MPV valves, mounts on to bulkhead fittings on the side of a Sand or D.E. filter. The advantages of a Multiport valve are that they have, well, multiple ports. This allows for more options than simply Filter or Backwash.

Multiport valves usually have 6 positions (Some Jacuzzi valves have 7 and some American valves have 8). The positions are usually labeled: Filter, Backwash, Rinse, Recirculate, Closed and Drain/Waste. These are described below in more detail.

When you move the multiport valve from Filter to Backwash, you are reversing the direction of water into and out of the filter. (which is where we get the word “back-wash”).

How Long do I backwash my filter for?

Backwash until the water runs clear out the waste line. Usually about 2 – 3 minutes. You may need to add water to the pool before or after backwashing. On a D.E. filter the last step is to add the fresh D.E. powder to the filter, through the skimmer.

When do I need to Backwash?

When the pressure gauge indicates a pressure rise of 8 – 10 lbs above the clean, or start-up pressure.

What Maintenance do I need to do for my Multiport Valve?

There really is no maintenance on a MPV. Just make sure to winterize properly if you are in the snowbelt.

Help! My Multiport Valve leaks out the waste line all the time!?

You most likely have “blown a gasket”. Remove the lid and handle assembly from the valve body and inspect for warped or damaged spider gaskets.

Help! My Multiport Valve leaks out the top cover all the time!?

Beneath the lid, there are several washers, a spring to give tension to the handle, and some stem o-rings on the stem that connects to the handle. One or more of these may need to be replaced. You can also purchase a Key Assembly, which is every-thing that comes out of the valve body when you remove the cover screws and lift it out by the handle. You can view a schematic of your valve in our valve parts department.

MULTIPORT VALVE POSITIONS
  1. FILTER: Keep it here 99% of the time, except when backwashing, rin sing or wasting.

  2. RINSE: Use this setting for about 20 seconds after backwashing to rinse tank.
  3. RECIRCULATE: Use this if the filter’s broken; at least you’re circulating the water.
  4. BACKWASH: Use this setting to reverse the flow in the filter and send water out of the waste line. Make sure valves are open or hoses rolled out.
  5. CLOSED: Put here to close off flow from the pool, usually to work on the equipment. Do not operate pump with valve in closed position.
  6. WASTE/DRAIN: Another filter bypass setting (like Recirculate), but this setting sends the water out of the waste pipe (hose), instead of returning it to the pool. Used to lower pool water level or to vacuum to waste if vacuuming fine, silty debris or algae.

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