Introduction: GeneralAire Furnace Humidifier Valve Repair

My drip fed GeneralAire furnace humidifier was leaking slowly.

The water feed could come in from either side.

I have three of these valves, all leaking, two of my own and another from a friend who had replaced his, so I had a chance to experiment. A new float valve assembly with valve seat costs around $25.00. I was going to buy a new one, but have time on my hands during this Corona Virus lock down.


Tools used:

4-40 NC tap, pliers, iPad Camera with macro lens, (the chips in the nozzle are hard to see without magnification)

Taig Mini Lathe, Tooth picks, fibreglass 'rod' (to keep track of brass nozzle and keep out epoxy), Sandpaper, medium and fine (to smooth surface of worn valve seat)

Material: Brass tube threaded one end (scavenged from something a long time ago)

Epoxy J-B Weld

Step 1: Cut Brass Tube

Cut the threaded end of the brass tube with lathe. A good tube cutter, dremel tool or fine hack saw would also work. With the lathe I was able to get a clean cut and an approximation of the original bevel.

Step 2: Thread Hole

Using 4-40 NC tap thread hole in valve nozzle to accept new brass nozzle

Step 3: Turn in New Nozzle

Step 4: Epoxy

Mix up JB Weld epoxy and spread around new nozzle. Appearance doesn't matter here, as long as epoxy doesn't go over tip of nozzle.

Allow epoxy to dry overnight.

Step 5: Repair Valve Seat

Make sure the valve seat is dry before starting this part. Sand the dent in the valve seat down till you have a flat surface to ensure a good fit. ( I tried gluing a piece of inner tube onto the valve seat but this made the seat too thick).

Use rubber gloves, the seat will leave a lot of black residue.

Step 6: Reassemble

Put the pieces back where they belong.

There is a small plastic shroud over the valve to direct the flow of water down.

I left out the float, arm, and valve seat to show the nozzle. If you made it this far, you'll know where the pieces belong.

Finally, no more slow leaks.