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ERV Project Brief

What  how and how much


GREENWAY ERV PROJECT 

Interesting ERV project This is my own record of my ERV home ventilation project. By way of this blog I hope to share my wee project with people who are interested and keep a record for myself as well. The cost is considerably less then HRV's and ERV's on sale in New Zealand and it's been a really interesting project the study up on.

A BIT ABOUT GREENWAY

This is a blog about my ERV project. My background is in industrial automation and control systems and I have recently got interested in home automation. Our system is based on Arduino, Hubitat Elevation and  MQTT. I have a gaggle of devices like Sonoff's and Arduino using MQTT, Thinger and occasionally Node-Red for experiments mostly. We wanted a low cost 150 mm system for our home using the most cost-effective parts we could find. I know its made of Coroplast and tape but if it works as I hope it will I will re-engineer some of the components in more durable materials.

THE PROJECT

There are 2 position-controlled valves 3 main fans, and 4 boost fans. Experiments show with a 6 Meter 150 mm duct and the main fan and boost fan at maximum we can get a flow in excess of 8 Cubic Metres per Minute.

The Goal

  • To create a cost effective ventilation system for our home
  • Reduce or eliminate condensation
  • Provide filtered clean air
  • Balance heating in the home
  • Determine best option ERV or HRV
  • Utilise Hubitat Elevation home automation hub




Roll your own for NZ$1500 https://greenwayerv.blogspot.com/ its eliminated condensation totally, even in September with frosts in NZ. The house is 5 years old so not many leaks, a balanced ERV seemed like my best option. The pollen filters also improve allergy symptoms in spring here too. Energy bill for September NZ$90 So economical, even temperature throughout the house.


What to do

 Looking at the specifications of propitiatory systems it seems that the fans are nothing special. They typically use Axial flow fans with AC voltage motors around 60 Watts seems suitable for our house. In order to allow me to do this without an electrical certificate my system is entirely 12 volt. 


The fans I have are pretty quiet to so it seems like win win to me less that US$30 each for the 60 W devices and US$16 for the boost fans.

Computer fans are a good low cost option. Quiet long lived and they have built in speed controllers too.


I am using two fan types in the system. I bought them cheaper than this





Specifications:

-- Size: approx. 120*120*38 mm

-- Voltage: 12(V)

-- Blast Capacity: 280.38CFM

-- Current: 5.0A

-- Rotate Speed: 7500CPM(r/min)

-- Noise Level: 64DBA

-- Wind Pressure: 24.60 mmH2O

-- Bearing: High precision double ball bearing

-- Operating Temperature: -10℃ ~ + 70℃

-- Storage Temperature: -40℃~+70℃

-- Power range: Plus or minus 15% of rated power supply

-- Insulation Resistance: More than 500 megohm

-- Fan Frame: Injection molding, PBT+ 30% glass fiber + VO class flame retardant.

-- Fan Blade: Injection molding, PBT+ 30% glass fiber + VO class flame retardant.

-- Suitable for workstation cooling/server CPU cooling.





Specifications:

Size: approx. 120*120*37 mm

Voltage: 12(V)

Blast Capacity: 267CFM

Current: 1.85A

Rotate Speed: 6500RPM(r/min)

Noise Level: 70.5DBA

Fan Interface board: 4 pin interface

Bearing: High precision double ball bearing



The larger capacity fans are used in the ERV heat exchanger and are the main fans for the system.  The others are lower powered and used as inline boosters or filter fans.















There is an additional 60 Wall fan in the exhaust 2 way Turbo valve to help boost exhaust flow in a purge situation. e.g. curry button

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