Home Forums Hunting & Shooting Hunter's Campfire How much water flow for a Carrier 49FH humidifier

I had a new AC put in July 2019 and they relocated my Carrier 49FH humidifier to the top of the plenum - it worked great. But now it’s only putting out 34% on my indoor weather station whereas last year it was around 45% or more.

I recently bought a new filter and there’s no change. I’ve measured water flow coming out of the bottom at 8 ozs per minute. So I took the line and solenoid apart, cleaned the inlet screen, and washed out the 2 rubber inner washers with some CLR and pushed a tooth pick thru both holes to clean out any minerals.

Put everything back together and with the inlet wide open I have 24 ozs of water per minute - 3 times as much as before. So I closed the inlet and opened it up 3 turns (I think 6 turns was max).

I'll try to tune it to about 16 ozs per minute to see how that does but I was running what a normal flow rate should be? I left a message on the service managers phone hoping to get a call back. Thanks.

I simply adjust supply flow until I see a steady trickle at the drain. Keep in mind that with a warmer winter, you may be seeing fewer furnace cycles, which means fewer humidifier cycles, unless you have it wired to run based on the humidistat.

Scott, do you have a recommendation for a flow control valve that I can install for my humidifier? This would go in the 1/4” line between the ball valve and the solenoid.
The ball valve sucks for tuning.

I adjusted it down to about 12 ozs of water per minute yesterday and saw no increase in the humidity percentage.

Today I’ll try to turn it down to between 5-6 ozs per minute thinking too much of a flow may cause the water column in the filter to drop too quickly instead of staying inside the filter longer.

3.5 gallons/hour. The solenoid valve should have a 3/32 orifice. I would just replace the solenoid valve assembly. The hole in the valve is very small and plugs easily.

Per carrier the recommended indoor humidity level should be 35%. We see it all the time in the trade that those indoor sensors are off. 45% seems very high for a home heated with forced air.

Well the 4-5 ozs per minute of water dropped it down to 30% this morning so I raised back to about 7 0zs per minute and it’s rising back up.

It used to make our windows sweat when the temp got into the 20’s but not this winter. I’l put a new humidifier in this summer.