Case Study: Filter & Bypass Installation
Technician: Lachlan Nash
Our customer had a Pool with an attached Spa, and the system had a cartridge filter that she wanted to change to a media filter as a media filter is much easier to clean and maintain than a cartridge filter.
A problem arose because the filtration system was fitted with a Viron P500 Variable Speed pump (which is more powerful than its baby brother, the P320), and Media filters have a lower threshold of flow rate than cartridge filters. Therefore, the Viron P500 would be oversized and cause pressure and flow issues when running at higher speeds.
Cartridge filters are often used in this situation if the filter pump is also used as a booster for the spa jets requiring more pressure & flow than a traditional filter pump. Traditionally, pool/spa “combos” were fitted with separate booster pumps, but modern variable speed pumps are perfect for this situation as their speed can be varied for different purposes. In this case, low speed for filtration and high speed for the spa jets means you only need one pump.
Our client wanted to change the filter but also wanted to keep the Viron P500 as it was new & also used as the spa jet booster pump. This meant multiple pump speeds would be necessary depending on what ‘mode’ the system was in. Spa jet mode would require the highest speed and pool filtration the lowest with vacuuming speed somewhere in between. So, we needed the ability to partially ‘bypass’ the filter at higher speeds. This meant the flow rate & bypass would need to be adjustable to ensure consistency and to make it foolproof.
What challenges arose?
- Need to bypass the filter.
- Need to know an accurate flow rate at different pump speeds.
- Need to adjust bypass in different system modes.
- Need to adjust pump speeds.
How did we overcome this?
- We installed a new media filter adequate to filter the pool water volume
- We installed an extra bypass valve & valve actuator
- We installed a Flow Meter Check valve to measure the flow rate
- Tested and configured new pump speeds
The client’s filtration system already included a Viron Connect 10 controller that also controlled the switch of valves from pool to spa mode with valve actuators (motors that attach to the top of valves). So, we were able to utilise that system to control an extra valve actuator for the bypass valve, thus automating the new bypass valve.
The flow meter check valve allowed us to monitor the pump speeds so the bypass valve could be set as accurately and efficiently as possible.
As the Connect 10 only changes the pump from speed 1, 2 or 3, the speeds need to be set on the pump itself. This is straight forward on the Viron P Series variable speed pump. We then configured ‘favourites’ in the Connect 10 so it is a one-button push to change from pool filtration to vacuum or spa modes, and the system automatically changes the pump speed and moves the valves to their correct position.
Lachlan prepared an instructional document for the customer to ensure they knew how and why the system worked as it did and what speeds had been set. A copy was also fixed to the connect 10 for any other technicians who might work on the system in the future.
Summary:
Working within the existing equipment’s capabilities and limitations, Lachlan managed to satisfy the client’s original request to replace the customer’s cartridge filter with a media filter when it was incompatible with the existing pump. His solution created a seamless, neat, efficient and user-friendly bypass.
