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Added a 60 Litre Plenum air-distribution box on the fresh air side

A bit or research and it seems a plenum on the outlet of the heat exchanger seemed worth a try.


60 Litre Plenum on the vent side. Seems to make the vents more balanced measuring the flow I can regulate the rate more evenly with one vent having less effect on the others, I'm going to add a presure sensor to the chamber see if there is any pressure in it

I noticed coupling between room vents. e.g. I set one room and move to the next then recheck the first vent and its flow rate was changed. I was never happy with all those Y junctions, a very poor manifold design I suspect. As an added bonus its made the vent even quieter too.


It works well within a range I can set the vent flows independently of one another, also the living room and office flows are much improved which have the longest ducts.



The flow at the office and living room are 50% higher if needed now which is great for working at home. The office got warm and sticky in the past, not anymore.

More Photos












Sound test







My reference material - homeguides.sfgate.com

plenum is an air-distribution box attached directly to the supply outlet of the HVAC equipment that heats or cools the air to make the house comfortable. The ductwork that distributes the heated or cooled air to individual rooms of the house connects to the plenum.



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The Heat Exchanger

  Under construction It took around 6 hours to layer the core Based on a 60 Litre Sistema box with a 400 X 400 X 350 6 mm Coroplast core. The fan speed controller is mounted on the end so it takes a 12V 10 Amp supply from the power system and 2 analogue 0 to 5 V signals for speed demand. The pink foam is a NZ$12 exercise matt which insulates it for both sound and heat quite nicely. 60 Litre Plenum on the vent side See  https://greenwayerv.blogspot.com/2020/10/we-added-60-litre-plenum-on-vent-side.html

Home Ventilation Heat Exchanger

 

The Experiment

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Heat Exchanger Low Ambient 86% Heat Recovery

  Drop on exiting air 2.9C Heating of incoming air 2.5C So 86% of the heat recovered

The ERV Data Acquisition System

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Drivers and Arduino Sketches for ERV Fans Control Testing

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