Wiring furnace Humidifier Help

PokeTheBear

I am adding an Aprilaire 400m to a Carrier Performance Series furnace. I am using the Carrier COR thermostat and want eliminate the Aprilaire humistat and control it through the COR thermostat.  I can connect it to the HUM port on the control board but that only activates it on a call for heat. I want have it activated anytime the blower is activated instead when humidity is needed. The only way I can see is to connect a 24v transformer and connect the hot line to the EAC-1 and then connect the neutral to the EAC-2. Then run both wires off of the transformer back to the solenoid valve on the humidifier. Does this sound correct? Or is there an easier way to connect without using the transformer? Thank you so much for any assistance. 

SuperTech

That would work, but it would also bring on the humidifier during a call for A/C if your furnace is equipped with it. You would need to wire in a normally closed relay to open the humidifier circuit during a call for cooling.  

That humidifier doesn't work very well without heated air to aid in the evaporation over the water panel. 

HVACNUT

That would work, but why not have control over it? 

JUGHNE

I learned that about not having warm air flow thru the water panel.....it just wastes the water and the panel.
Especially noticed the lack of heat on heat pump systems.

SuperTech

The 400 series uses a water panel that absorbs the water like a sponge, they don't use a drain and have water flowing through them. However it will still ruin the panel rather quickly, and foul up the bottom of the tray and the floats that shut off the solenoid when they tray fills. It all becomes full of sediment and everything else that is leftover when the water finally evaporates.  

Use the control, set it up so it doesn't bring the blower on without a call for heating.  

HVACNUT

A steam humidifier like the Aprilaire 800 is the only way to go. Fan on with a humidity call. I've done a few with the outdoor sensor and have been called back to remove it. Mostly in the tighter houses.

mattmia2

Wait so that is like a flow through but it collects the crap that is supposed to flow through in a pan then it puts a float in the pan of concentrated minerals and expects that float not to stick and cause a flood?

Jamie Hall

mattmia2 said:

Wait so that is like a flow through but it collects the crap that is supposed to flow through in a pan then it puts a float in the pan of concentrated minerals and expects that float not to stick and cause a flood?

A lot of stand alone humidifiers do that. In fact, any humidifier which isn't basically flow through -- such as, perhaps, a simple spray with a collector tray and recycle line -- will do that. If water is fed to the unit and evaporated, but there is no continuous drain for the excess water, whatever was in the water when it came in is going to stay there. Dust. Minerals. Crud. Whatever. Got to get rid of it somehow!

SuperTech

mattmia2 said:

Wait so that is like a flow through but it collects the crap that is supposed to flow through in a pan then it puts a float in the pan of concentrated minerals and expects that float not to stick and cause a flood?

Its a completely different panel than the flow through. Aprilaire #45 panel, the same size as the #35 flow through panel. Bad things happen if someone puts a #45 where a #35 should be, or vise versa. 

I've never seen a 400 cause a water leak, even when neglected. The panel and humidifier can get pretty gross if not replaced and cleaned annually. It's a builder grade humidifier.  The Aprilaire 800 is definitely much, much better.  

HVACNUT

There's 2 float switches on the 400. And if they both happen to fail due to lack of maintenance, there is a drain. 

unclejohn

The 400 is a waste of time and money. Doesn't waste much water though. Doesn't evaporate much water either.