Navien CH-240 ASME Outdoor reset Connection

vicpj1

HI, I have a Navien CH-240 ASME and I'm trying to install the outdoor temp sensor. I bought the sensor pt. # NASS9EXOS001 but it didn't come with a cable.I thought I could connect thermostat wire right to the circuit board, but there is a small 2 pin connector on the board. Has anyone installed one of these. Any advice would be greatly appreciated...   Thanks.. Victor in Swansea, Ma.

JStar

Sensor

The wiring harness comes with the boiler. You may need to order that, too.

vicpj1

wiring harness

Jstar thanks for the reply. I have searched on-line for the harness, but can't find anything. Is that something i need to order from Navien...

JohnHenry_2

The connector

The pigtail connector comes with the unit. It has blue wire on mine. If it didn't come with the unit, call Navien and have them send you one.

vicpj1

wiring harness

I called Navien, they are sending me the wire with the molex connector free of charge.   thanks for the replies....

JohnHenry_2

If you're working on your own system

You might want to have them send you a service manual if you don't already have one. The I & O manuals come with the unit and are available online but the service manual seems to have to come directly from Navien.



I've found their support to be excellent.

vicpj1

Service Manual

Heres a link for the service manual



bostonheatingsupply.com/Navien/CH%20Service%20Manual.pdf