On 10/24/2011 11:20 AM, N8N wrote:
....

There is a mechanical humidistat, but it seems to me that the flow
rate of the water is such that it might overpower the drain if the
water isn't actively evaporating off the panel....

The solenoid should shut off the water when there's no demand...tied w/
the sail switch since you have one or from the HUM contact on a furnace
w/ that logic on the board.

Generally, the old Honeywell sail switches I'm familiar with were
dual-function humidistat/flow switch using a humidity-sensitive
lever-connection that stretched/shrunk as humidity went up/down that
controlled the contacts.

As noted, replaced both w/ the solid-state humidistat and the new
furnace has the HUM logic onboard so all is much simpler that way.

I thought you said you do have a solenoid; doesn't it shut the water off
when not demanded? If not, what _does_ it do?

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