Connecting Venmar HRV to Lennox Communicating Furnace & Heat Pump

[jcanzo86]

Good Evening All

I recently had a new Lennox HVAC System installed (Furnace SLP99UHV + Heat Pump SL25XPV) as well as a S40 smart thermostat. I'd like to add a Venmar HRV110 that I recently purchased but I thought I would reach out to the forum and see if I'm going about the connections the correct way.

Being that this is a communicating system the manual for the S40 indicates that a EIM (Equipment Interface Module Part# 22X18) is required in order to connect the HRV to the system.

When reviewing the manuals for both the HRV and the EIM I'm struggling a bit with the connections required, the EIM manual shows a standard terminal block found on most HRV's while the terminal block on the Venmar is a bit different (I'm assuming given that it has the internal relays)

Below are the shots from the Lennox EIM manual for connecting an HRV/ERV as well as the instructions from the venmar manual to connect HRV using dry contacts.

Here is what I'm planning to do:

Being that the Venmar HRV110 can be controlled by the furnace and operate in auto mode I'm going to connect
     - Vent terminal from the HRV to the W1 terminal on the Lennox EIM
     - Connect R terminal on HRV to W3 Terminal on Lennox EIM
     - If necessary I can connect the common however I don't believe the terminal is live when the EIM is in
       Vent configuration.

I'm hoping I'm on the right track here and I've interpreted the instructions correctly, if there is any flaw in my plan or a better way of doing the hookup I welcome any suggestions.

Thank you all for you're time and expertise

[tvtime15]

Did you ever get this to work?

[g-unit]

Good day, eh.

Had a similar issue connecting a Home Depot purchased Venmar HRV110 to interlock with a Lennox electric CBX40UHV with ECB40 control board. The Venmar installation manual unfortunately does not mention this "how to" interlock connection.
With respect to OP, connecting the HRV J13 to furnace W1 & W3 is bad mojo; instead, on the HRV110 J13 Terminal Board (V,Y,W,C,Gf,G,R) connect one end of the supplied 22/4 cable's Red wire to R, and the Green wire to Gf using the appropriate length to reach the low voltage 24VAC connections on the furnace's control board. The R slot on the J13 terminal board represent the HRV internal relay's NO (Normally Open) contact; the Gf is the COM (Common) contact, you need not worry about the NC contact. The R wire from the HRV connects to the furnace 24VAC "R" terminal, and the Gf wire connects to the furnace 24VAC "G" terminal. The unused yellow and black wires on both ends of the 22/4 cable can be wound around the cable and secured with electrical tape.
Now when you turn on the HRV wall switch to either Int/Min/Med/Max the furnace fan will spin up to its lowest speed and bring fresh air in and push stale air out.