Greenway

 

  Measured Mass Flow in Exhaust Port of ERV  4.4 mS through 15cm duct = 0.0777 m/sec3  so 165m3 is removed in 35 Minutes DAS Reports 0.102 mean with the pitot tube in the exhaust duct 

I think I'll build one of these https://woodgears.ca/dust_collector/impeller.html Credit  https://woodgears.ca/ I need to cost this out properly I suspect the valves will push the cost up to high might bi simpler to build a fan What about this This might be better and more compact The valves I want a booster exhaust air mover that can say exchange all the air in the house in 15 or 20 minutes The calculation above shows I can do this with one or two 75cm gym ball lungs. So the idea is make a rolling diagram or ball compressor from 2 NZ$12 gym balls and a windscreen wiper motor. So 45 decrees of travel in 2.5 seconds? A wiper motor can do that but the Torque needed at a radius of say 50cm would be?????? Hard to say these is virtually no air pressure however the ball has significant wall thickness best discovered by experimentation,. I think. Torque needed to excerpt 2kg of thrust at 50cm is approximately 9.81 Nm unsurprisingly, or 1kg/Meter. Can a wiper motor deliver 1kg at a half me

Live data feed from Hubitat Cloud   

Smart control: - reduces power costs of air handling units - adjusts ventilation to your everyday needs - provides a wide range of control options It has been estimated that smart control allows to half the average cost of electricity for ventilation.

 We get around a 1C boost to the fresh air from loft heat exchange with the duct. The loft is consistently between 4 and 15 C hotter than the outside air and even at night boosts heat in the fresh air duct to the living room. An unanticipated benifit

4 port fan working

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

  We have a data logger running every 6 minutes we save stripes of data from Hubitat to disk using a call to my Tiny Webserver in Rule Machine  See Web Server Source C#

 

  Progress over the weekend with the ERV DAS The 999's are me testing the sensor disconnected response. I have a Pitot tube left over from an RC plane I think I might put it in the inlet air stream Pin assignment in the Arduino sketch DHT dht[ 4 ] = {DHT( 4 , DHTTYPE),DHT( 0 , DHTTYPE),DHT( 2 , DHTTYPE),DHT( 14 , DHTTYPE)}; There are 4 DHT22's inside heat exchanger lid, shown below. Sensor locations Arduino code #include < Arduino_JSON . h > #include < ESP8266WiFi . h > #include < MQTT . h > #define LED_PIN LED_BUILTIN //LED_BUILTIN is built in LED #include "DHT.h" // Uncomment whatever type you're using! #define DHTTYPE DHT11 // DHT 11 //#define DHTTYPE DHT22 // DHT 22 (AM2302), AM2321 //#define DHTTYPE DHT21 // DHT 21 (AM2301) WiFiClient net ; MQTTClient MQTTclient ; const char ssid [ ] = "Network" ; const char pass [ ] = "DF@#$%" ; // the IP address for the MQTT server char MQTTip [