Thanks everyone for the suggestions, the level of feedback that has been provided has been excellent.
My goals for the UV system is to run it for a period of time per day (3 times for 2 hours per day each, 6 hours total) as a proactive measure. If there is a need, then it will run 24x7, with a substituted lower volume return pump for the treatment period and close off the bypass line to process 100% of the water.
Due to budget, the units I have purchased are not high quality/high output, so water throughput is a challenge as is the dwell time. They are low cost non branded Chinese units, so the rating information I have for them may be overly optermistic.
Based on the feedback people have provided (both here and from other sources), the design has now been somewhat changed.
This will hopefully give me a unit, that I can adjust the dwell time of the water passing through it, plus provide for a greater volume of water being processed than a single or serial set of units. I have remained with the parallel design at this stage, though I don’t really have a reason for this. My initial thinking was for more water flow, but the more I think about this, the realisation I am coming to is that the only thing I should care about here is the maximum kill rate, hence low water flow.
By changing the design to having both the input and output lines at the top of the manifolds and closed manifolds, I shouldn’t be able to run the units dry and I’m of the belief that it will provide for as equal a pressure as possible across all of the UV units, hence balanced throughput.
Im planning on using a removable connection between each of the UV units and the manifolds (not shown in the diagram). So in the case of maintenance or failure, I can replace the entire UV unit or substitute it with capped piece of pipe at both ends.
New Design
Is there anything that anyone feels is missing or that I may have misunderstood?
