Is it safe to prewire a HAI RC2000 for future OMNI IIe

[PAPutzback]

I ordered the RC2000 thermo and when I go to install it I am wondering if it is OK to prewire the cable to it from the location I am planning on putting the OMNI IIe.

I'm also curious about the humidifier connection. Do I just leave the humidifer on high and run a line from the power line on the humidifier to the thermo and the thermostat just turns it off and one when needed or is there an available connection on the humidifier for this purpose. The humdifier is a Honeywell unit mounted on the side of my furnace.

 

[dutchyn]

I'm also curious about the humidifier connection.

My electrician ran 2 conductors from the humdifier to the H and C lines on the RC-2000. I assume they know what they're doing.

 

[tpboyce]

I'm also curious about the humidifier connection.

My electrician ran 2 conductors from the humdifier to the H and C lines on the RC-2000. I assume they know what they're doing.

There are two different humidifier types. One uses a bypass duct between the air return and the conditioned plenum. These often work off of 24 volts, which is the output of the Humidifier terminals according to the directions. Some humidifiers, like mine, do not use the bypass and use a blower to force air over the element. These will require a relay to sense the 24 volt current and close the circuit for the humidistat. In at lease my scenario, there is also a sensor that determines if air is flowing in the plenum. I beleive that this can also be bypassed, as the humidistat in the HAI will only trigger when the fan is going (or so I think).

 

[dutchyn]

There are two different humidifier types. One uses a bypass duct between the air return and the conditioned plenum. These often work off of 24 volts, which is the output of the Humidifier terminals according to the directions.

That must be mine -- or the electrician messed up.

These will require a relay to sense the 24 volt current and close the circuit for the humidistat.

Be aware that the 24V wiring for HVAC seems to have standardized on alternating current (AC). I believe that you'll need some sort of diode+capacitor, or 4-diode rectifier to convert the 24VAC into something a relay can trigger off of. I'm currently trying to figure out what part that might be, because I want to monitor the 24VAC fault lines from my geothermal units.

The humidistat in the HAI will only trigger when the fan is going (or so I think).

This would be good -- however I can't find any details in the manuals.

Chris D.

 

[WayneW]

These will require a relay to sense the 24 volt current and close the circuit for the humidistat.

Be aware that the 24V wiring for HVAC seems to have standardized on alternating current (AC). I believe that you'll need some sort of diode+capacitor, or 4-diode rectifier to convert the 24VAC into something a relay can trigger off of. I'm currently trying to figure out what part that might be, because I want to monitor the 24VAC fault lines from my geothermal units.

Just use a 24VAC relay - the coil is energized by 24 volts AC. Very common in the control industry, hard to find at Radio Shack though.