Skuttle Current Sensing Relay A50

The relay is clamped on to the blower wire and has an internal switch that closes when the blower receives current. The blower voltage can be 120v or 240v, only the is amperage important. The internal switch is electronic and can only switch on or off 24 volts, such as any 24 vac humidifier.

HFT2900 Dimension and Mounting location

The HFT2900FP is best mounted as shown. Check that you have enought room.

White-Rogers HFT2900FP Versus Skuttle 2002

The White-Rodgers HFT2900FP is the same as the Skuttle 2002. Skuttle manufactures the HFT2900FP for White-Rodgers and applies their logo.

All items included with the 2002 are also included with the HFT2900FP. As well as all internal parts are the same.

What is Flow-Thru Humidifier?

The term Flow-Thru refers to water trickling through the water panel and out a drain. The advantages of a flow-thru design is reduced maintenance and no standing water. Scale from calcium and lime gets flushed out of the water panel and down the drain. The water panel is an aluminum mesh with a porous coating that inhibits growth of slime and is easy to change (once a year).

The disadvantage of the Flow-Thru is water usage. We are in the northeast where this is not an issue. We get a flat rate water bill unless there is excessive usage then the rate goes up. The Flow-Thru humidifier does not cause excessive usage.

The Flow-Thru is an evaporative humidifier and requires hot air. If not using hot air then hot water should be used. We see little humidity gain if our Flow-Thru humidifier is operating with cold air (and cold water). We run our blower on constant to best utilize our electronic air cleaner, but our humidifier is wired to only operate only when there is hot air and works very well

By-Pass Versus Power Humidifier

The term By-Pass or Power refers to the driving force behind the air flow. The Power humidifier (aka Fan Power) uses a fan to draw the air thru the humidifier. The ByPass humidifier uses a 6" diameter duct that connects the supply to the return duct. In the ByPass configuration the air leaving the furnace is routed back to the supply. The warm air leaving the furnace takes this short-cut of least resistance and bypasses the long trip down the duct work, in to the house, and back through the return. The ByPass is the 6" round duct work shown to the left. During the the hot humid A/C season the ByPass duct should be closed with a butterfly valve since the air flow through the humidifier would not be needed. The Power humidifier uses a fan to draw air in from the duct and through the humidifier and exhausts back out in to the duct. The air is drawn in through duct at the center of the humidifier and back out in to the duct at the sides. The power humidifier should be mounted in vertical warm air flow. The HE225 and HE265 are ByPass humidifiers. The HE365 is a fan powered humidifier

Manual Versus Automatic Humidistat

The indoor humidity level needs to be set based on the outside temperature. This is to prevent water from running down the windows. The cool air near the windows can not hold the humidity and water will condense on the glass. To prevent this condensation, the indoor humidity level is sacrificed by lowering the humidistat.

A manual humidistat needs to be set back as the season gets colder. An automatic humidistat (such as the Aprilaire 60) adjusts the humidity by using an outside temperature sensor.

The Honeywell automatic humidistat (H1008A) determines the outside temperature based on the furnace duty cycle or with an optional outdoor sensor. Below the Honeywell owners manual discusses this feature they call HumidiCalc.

White-Rogers Warranty

The White-Rodgers warranty for our new HFT2900FP humidifier is five years. Our customers simply ship us the defective part. We inspect and test and confirm defective. We then ship back a brand new part.

The problem with humidifiers is typically due to water quality. Parts will corrode or freeze up with calcium and lime deposits. The mineral deposits from hard water will contain salt that can corrode the motor. Water filtration and treatment is the solution.

The warranty does not cover problems with corrosion.