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What is a humidistat?
A humidistat is similar to a
and it responds or is designed to be sensitive to changes in relative humidity. The humidistat is used in several devices such as
and microwaves. In humidifiers and dehumidifiers, setting the humidistat by adjusting its controls can help maintain the relative humidity conditions in a refrigerator or greenhouse. In microwaves it usually is used in conjunction with the “smart cooking” feature.
Listed below are a few questions answered by the Experts on humidistat.
Can I use a Honeywell humidistat as a replacement for my Aprilaire 600 humidistat which is part of my Aprilaire humidifier?
This is dependent on which thermostat you received along with the Aprilaire. They had a wide range of humidistats at different times. Usually the humidistat will have a model number on it. You could use the Honeywell H89 humidistat on the 600 humidifier. However if the old thermostat had more than two wires passing through it, reconfiguration of the wiring may be required.
Explain the mechanical operation or functioning of the humidistat?
When humidity rises above the set point on the humidistat, a switch will get turned on to activate the de-humidification function. A switch can be open or on and closed or off. The switch mechanism and functioning of the humidistat is as detailed. When humidity rises, the switch will close and complete a circuit, which initiates voltage flow to the receiving load. A signal is sent to the air handler to reduce the air flow by 15% to 20%. The load then drops slightly on the
causing it to cool and the lower velocity exposes the coil to air longer causing an increase in the intrinsic moisture capacity of the unit. Similarly when humidity drops below the setting, the switch opens, thereby creating a break in the circuit and turning off the humidification function.
Explain if and how I can wire a humidistat to a swamp cooler?
A humidistat is essentially a switch which is programmed to close at certain humidity levels and open at other levels. Your goal is to locate the spot on the swamp cooler that allows the humidistat or an open or closed switch to start or stop the cooler based on humidity levels. Generally it should be connected where the thermostat would be installed or through the control panel of the swamp cooler. The humidistat is a low voltage (24 volts) connection and most swamp coolers are usually not equipped with 24 volts. In the case of a 120 volt swamp cooler, a 120 volt humidistat will be required, which stops power to the unit similar to a light switch. The other option would be to use an isolating relay, a transformer and a 24 volts thermostat.
I am connecting a furnace and air conditioner (AC). How do I wire a 98001i2 programmable thermostat/humidistat?
Case details: The thermostat has a cable with five wires, with four connected to the thermostat/humidistat. The connections are as follows: Green to G; Red to RC; Yellow to Y, and White to W. There is also a short wire connecting the RC post to the RH post.
Red wire goes into R, yellow into Y1, Green into G and Y into E/W1. If there is no wire connected to the old thermostat in the C or common post, then there is no C wire. This particular thermostat/humidistat requires the C connection and it has no battery power. The fifth wire which is in the wall needs to be connected to the C terminal. Next connect the same color wire to the C terminal of the furnace control board. The
usually has two wires coming from it. One wire connects with the yellow wire going to the thermostat/humidistat. The other wire of the outdoor A/C hooks to C and the fifth wire is what would need to be hooked to this.
The Humidistat is fairly simple device with a straightforward mechanism. The common problems you can face with it are listed above. With specific instructions you can arrive at the problem area and work upon resolving it. Therefore to understand better, insights and information from Experts will be helpful and useful to tackle the problem immediately and effectively.
Recent Humidistat Questions
Why does the Y terminal (sometimes but not always)get energized
Why does the Y terminal (sometimes but not always)get energized (and ac comes on) when i jumper R & G at the terminal strip of an appliance with the t-stat is still connected?
Hello. I'm putting in a replacement AprilAire 560 humidifer.
I'm putting in a replacement AprilAire 560 humidifer. There is a male connector on the furnace circuit board that's labeled HUM 24VAC.
I assume I' suppsed to connect the humidifier wire to that connector, but the guy who installed the furnace recently said to strip the shielding off the wire, and connect the exposed red / white to the C and W terminals on the circuit board...even though there are already other wires connected to those terminals.
I did that, and it blew the secondary voltage fuse.
So my question is...should I definitely connect the humidifier wire to the HUM 24VAC connector on the circuit board, or try the terminal connectors again once I get a new fuse.???
I have a Goodman furnace and Generalaire bypass humidifier
I have a Goodman furnace and Generalaire bypass humidifier that were installed at the same time. The humidifier hasn't worked for nearly two years (both are about five years old). Both the humidistat and solenoid have been replaced with no effect. When I test the wires to the solenoid for continuity or current, I get nothing (whether the furnace is running or not). Leads are connected to the logic board on the furnace on the C (common) and W blocks. Is this wired the wrong way or what should I be looking for (before paying for a service call).?
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