Honeywell 24v HW Gas Control Valve Harness Connector Purpose?

[Clog]

What is the purpose of this 3 pin wire harness connector on the front face of the Honeywell WV4262B1114
hot water heater gas control valve?

My hot water heater functions fine, I'm just curious what this unused port is for. For example, is it an input port for external smart home systems to control power to the gas valve, shutting it on or off remotely?

The interface looks like a 3 pin computer fan connector one might find on a motherboard.

The pins are male on the gas control valve.

The technical service representative at AO Smith was not able to answer the question, because the port is not utilized in the serial number of the hot water heater I had to submit in order to ask any question at all.

I recognize this Honeywell valve as a unit that has been installed in many different brands of hot water heaters, including brands that are not affiliated with AO Smith.

Do you knw what this port is for?

Thanks!

 

[Phog]

I'm going to put my speculation hat on here. It looks an RS232 interface.

Typical controls on a Bradford White water heater
HOT is 120 degrees and every letter after that is hotter.

 

[Sponsor]

 

[Clog]

I appreciate any speculation. At first I was skeptical of RS232, as I've only interacted with 9 pin versions of that serial port standard, and this port only has 3 pins. However, looking online, I did find dog bone harnesses that bridged 3 pin Molex connectors to 9 pin RS232 serial port connectors... so the speculation was fair.

More importantly, it inspired the idea of the pins transmitting data signals, rather than trigger signals.

With my mind opened to this possibility, I expanded my search to other Honeywell Gas Control Valves for highly featured (flue damper, power vent, FVIR, etc) water heater tanks, and found another control valve family that has the same visual form factor as what is photographed above.

The valve above is the WV4262 family, and a similar looking valve is the WV4460 family.

In the later family, I found an instruction manual this evening that identified the mystery 3 pin Molex port as being Honeywell's EnviraCOM™ Remote Communication Port.

So this is similar to what I was hoping for... a way for smart home communication systems to be able to communicate with the gas valve, which may include the ability to remotely shut it off. But it is also more than what I imagined, as the EnviraCOM™ communication system has a way to retrieve up to 10 previous failure codes retained in the control valve's non volatile memory, and can also be linked to an alarm system (apparently proprietary to Honeywell.

I'm still learning about all of this, but if anyone reading has any experience at all with Honeywell's EnviraCOM™ system, in either the plumbing or HVAC iterations, please post your insight and experience. Thanks you!

 

[Phog]

RS232 deployments do typically utilize a D-sub DB9 or similar 9-pin connection, however only 3 conductors are actually required for data transmission, the rest are to do with handshaking etc and often not implemented for simple, short distance comms. Other common 3 wire capable protocols that Honeywell may have used are RS485 (half duplex) or I2C (I-squared-C) which is a chip level data bus. Of course this information doesn't help answer your question about the EnviraCOM system features. Which I'm not familiar with, just speculating further that it probably uses one of the above comms standards to transmit its data.