Aprilaire 560 Humidistat 4016
#1
11-16-05, 08:08 PM
Aprilaire 560 Humidistat 4016
We have an Aprilaire 560 system and recently replaced the humidistat 4016 because the water was constantly running even when the heating system was off. The new humidistat was installed and it worked well for 3 weeks and then the problem returned. The water is constantly running even when the heating system is off. I have checked the solenoid and it works (disconnecting the wires to the solenoid keeps it closed). I can close the solenoid by turning the humidistat dial to a lower setting. Is there another part that needs to be checked in this system?
#3
11-19-05, 05:12 PM
The humidistat is wired into the existing control board on our Lennox 80MGF furnace. There is no separate A50 relay. I suspect we need either a new control board or someone to rewire the humidistat to use the existing ACC connections with the transformer. I do not have much experience with the present wiring scheme.
#5
12-10-05, 08:50 PM
Thank you for the assistance. I was able to follow the circuit diagram that came with our gas heater and determined which terminals the humidistat was wired to. Because the original board was used to control the power to the humidistat (24V plus an on-board relay), I decided to simply add an A50 relay into series with the humidistat. So the humidistat gets its 24V from the board as controlled now by the A50. It works fine now and saved the price of a new board and the local union wages. Pretty easy once you know what to look for.
