Humidifiers and Dehumidifiers - Honeywell HE360A on my Heil 5000

The inside furnace label says Inter-City Products with a model number of NUG5100BHA1, probably made around 1993 or so.

I have read most of your HE360A posts here and have gotten a good orientation. At this point I have installed my new 360 to the duct work and am wanting to get my ideas together before doing any more duct cutting or wiring. I really dislike the looks of the sail switch. It seems like a failure waiting to happen, aside from the fact that it probably restricts air flow in the return (comments welcomed). I would also like to avoid the A50 relay if possible but I do not see any HUM or other accessory connection in looking through the furnace wiring diagram. Can you confirm this for this furnace? Is there any other option in this case? I would really like to be able to plug the humidifier into an outlet controlled by the furnace, and then just wire only to the humidistat for switching purposes.

Second question, if I must resort to the A50, I am concerned about a post in your archives which described a problem where the A50 relay properly detected the blower going on, but would not shut off when the blower stopped. The advice there was to replace the thermostat wiring with an unshielded, stranded variety and maybe replace the thermostat if the first thing didn't work. Is the A50 device generally a reliable solution?

Third, it appears that my thermostat wiring was installed along with a separate 2 wire cable (currently unused) that seems perfect for installing a humidistat in our living room. Can you comment on whether this might work better or worse than placing the humidistat in the return duct near the furnace? Are there any limits on the length of this wiring for it to work right?

Thanks in advance.

The inside furnace label says Inter-City Products with a model number of NUG5100BHA1, probably made around 1993 or so.
That's an older furnace, and afraid you going to have to use the sail or A50. The A50 is going to be a better control to use than the sail switch.


Third, it appears that my thermostat wiring was installed along with a separate 2 wire cable (currently unused) that seems perfect for installing a humidistat in our living room. Can you comment on whether this might work better or worse than placing the humidistat in the return duct near the furnace?
Not sure where the furnace is at, but if it's in an odd area, where you can't get to at with ease to adj, the humidity setting, then use the living room location.

The return can be better since you can get an whole house humidity reading than just the living room reading.

Are there any limits on the length of this wiring for it to work right?
Nope.

Thanks for the response. I did go buy an A50 and put it in series with the humidistat. Seems to work fine, I will really see when the heating season cranks up.

It would also be nice if I could have a switch in that circuit that only enables the humidifier when the thermostat is calling for heat. The reason is that we like to keep the fan on all the time (to keep the air more filtered). If I want to have the A50 switch with the fan, and another relay close with the want heat wire, what kind of relay should I get?

Any single pole/single throw relay will work.