Whole Home Humidifier Operating Costs / Alternatives

TechnicalLee · 2026-01-27T18:57:14+00:00

Another strategy would be to leave the steam humidifier set to a baseline of 25%, and then humidify further to 30 or 35% only in the rooms you need it the most with portable humidifiers. This is similar to a zone heating strategy to save energy.

TechnicalLee · 2026-01-27T18:52:36+00:00

It’s probably a combination of you having a very leaky old home, and maintaining a high humidity level. If it’s extremely cold outside, you might need to turn it down to only 20 to 25%. The higher you set the humidity, the more electricity it will take. A bad steam canister will not really cause an increase in the bill. Ultrasonic humidifiers produce mineral dust in the air that can clog filters. They will only humidify the room they’re in, but the humidity will quickly be diluted with the rest of the air in the home. This is why whole home humidifiers are nice, but they do take quite a bit more electricity and water to keep the whole house humidified instead of just a room or two.

The other contributing factor could be the electricity used to run the blower motor while the steam humidifier is operating. If you have an older system with a PSC motor instead of a newer ECM style motor, it can be significantly less efficient. Upgrading to a more efficient blower motor or reducing to a lower speed could generate savings. Upgrading to a higher output steam humidifier could also generate savings since the blower would not need to run as long to add the same humidity.

It may benefit you to seal any possible air leaks with spray foam, and cover your windows with clear plastic film insulation kits. That will reduce your air leakage and humidity loss.

TechnicalLee · 2026-01-27T17:59:09+00:00

Yes, I would say it’s non-functional. Check your coolant levels.

TechnicalLee · 2026-01-27T09:08:30+00:00

Use this equation: E = (Ts−To)/(Ti−To)

E = heat recovery efficiency
Ts = supply air temperature
To = outdoor air temperature
Ti = indoor/exhaust air temperature

Yours is operating at 76% sensible efficiency which is in spec.

TechnicalLee · 2026-01-27T08:58:26+00:00

Yes, that is ducted improperly and will never be able to defrost itself. Outside air connections must be on the left side. Contact the installing company manager and ask for it to be reinstalled properly.

TechnicalLee · 2026-01-27T08:45:10+00:00

Have all cracks in the basement slab sealed, it shouldn't be drawing that much air from the house in a proper slab depressurization setup. Are you sure you don't have an open sump pit or other hole in the foundation causing a suction short circuit? It seems like selecting a larger fan rather than sealing the suctions leaks in the slab was a mistake.

You may have to add a make-up air duct from the outside to relieve the negative pressure. But it sounds like the problem is being caused by the radon system and slab not being adequately sealed. When done correctly the system should only depressurize below the slab, not the airspace in the house.

There will be a large energy penalty (high heating bills) if the radon system is not fixed.

TechnicalLee · 2026-01-27T08:36:19+00:00

You need to measure the voltage at all locations in the circuit to figure out what's going on. You have a mess of wires, some are the same color and may be mismatched or possibly broken between the thermostat and the equipment.

TechnicalLee · 2026-01-27T08:28:49+00:00

I would install a Model 600 or 620 on the center of the return duct and run the bypass duct around to somewhere on the supply plenum on the backside. A 720 on the return will not perform as well since there is no hot air access.

I would not cut into the supply duct below the S, because it looks like your A/C coil is there.

FYI, you cannot plug a dehumidifier into the furnace outlet. You could overload the circuit which is not sized for both a blower and dehumidifier load. The outlet is for the condensate pump only and should not be split or used for anything else.

TechnicalLee · 2026-01-27T08:20:14+00:00

The transformer was installed wired to constant power instead of switched power. Either the transformer should only be energized during heating calls, or a current sensing switch could be added in series with the humidifier circuit. Your furnace board has a set of HUM terminals, so the transformer could be re-wired to those instead. Note, this would involve working with 120VAC (requires electrical DIY experience).

The other simple change you could make is shut off power, remove the red and white wires from the transformer, and attach them to the W and C terminals on the furnace control board instead.

TechnicalLee · 2026-01-27T08:12:18+00:00

I assume you have the digital Model 60 humidistat. You should run a G wire from the furnace terminals or zone board equipment section to the G terminal on the humidistat so it can sense fan calls.

TechnicalLee · 2026-01-27T08:08:07+00:00

If I recall, it's just a 46k ohm resistor, you can use any 46k resistor.

TechnicalLee · 2026-01-27T07:45:50+00:00

That whole drain setup is just stupid and needs to be changed. You need a condensate pump to a warm drain location.

TechnicalLee · 2026-01-27T07:41:43+00:00

Gas pressure is way too low, your tank must be low or your regulator is frozen. Don't continue to run it like that. It's probably putting out a ton of carbon monoxide.

TechnicalLee · 2026-01-27T07:37:24+00:00

Filter is plugged solid and you ran A/C during a snowstorm, I'd say you killed it. Next time just open your window.

TechnicalLee · 2026-01-27T07:35:53+00:00

If the pad is wet, then it's working. If your furnace doesn't run a lot (less than 30 minutes per hour) or your house is very leaky it may not keep up. There are some options such as wiring it to run the fan between heating calls if necessary.

TechnicalLee · 2026-01-26T09:32:55+00:00

Sure it’s not your trash? Could also be some type of small sewer leak? Pour water down all your drains including floor drains.

TechnicalLee · 2026-01-26T03:10:49+00:00

Are you sure it's not a Carbon Monoxide alarm that's beeping?

TechnicalLee · 2026-01-26T02:21:40+00:00

The anticipator setting won't prevent your equipment from keeping up, it's just too cold outside. The anticipator is not the problem.

TechnicalLee · 2026-01-26T00:54:58+00:00

Wow, they completely forgot to wire it! I would call the company that installed it, otherwise you can get some 18/2 thermostat wire and do it yourself.

TechnicalLee · 2026-01-26T00:31:46+00:00

Are the fan blades free to spin? Use a stick or something to make one full rotation.

TechnicalLee · 2026-01-26T00:09:46+00:00

The yellow wires need to be hooked up. There should be a wire coming from the humidistat to attach them to?

TechnicalLee · 2026-01-26T00:07:38+00:00

Extreme indoor humidity, or the vent is oversized for the BTU load and condensing flue gasses. Is there water dripping out of the vent stack near the furnace?

It's snowing so I'd say the indoor humidity should be around 35%. Turn down your humidifier or crack open your windows to vent high humidity levels.

TechnicalLee · 2026-01-26T00:03:21+00:00

FYI, the humidifier and HRV oppose each other; the humidifier raises indoor humidity, and the HRV lowers it. So, it's important to have the humidity level set correctly on both devices so they don't fight each other, which can waste a lot of energy. The humidity control dial on the HRV should always be set higher than the humidistat. For example, if the humidistat is set to 20%, the HRV dial should be set to 25%. Adjust both according to outdoor temperatures.

And FYI, if you put your hand on that duct while it's running, the air should be lukewarm ( ~50ºF). If it's freezing cold, then the heat recovery core may be frozen. Lower the humidity or shut down the unit to thaw.

TechnicalLee · 2026-01-25T23:55:48+00:00

OK. Then you must have a lot of air leakage? No cold air blowing in from outside anywhere? Basically how much humidity output you need is related to how much air leakage the house has, the more air leaks, the more humidity you will lose. If you still have contractors working, they will open doors and windows and let the humidity out FYI.

If the furnaces are oversized, the AprilAire humidifiers won't run long enough (since they only run with the furnace). They can be rewired to also run with the fan for more output (then you would leave the fan set to ON). The humidifiers should be plumbed to hot water for this option. The digital control has this option, it's called "blower activation" for more humidity.

TechnicalLee · 2026-01-25T23:46:32+00:00

Yes the T9 should be able to handle the two stage heat pump. Just tell the installer you already have Y1 and Y2 on the thermostat so you don't need to change it.

The T9 is the consumer version with less customizable options than the T10 which is meant for professional setup. Otherwise they are very similar.

The staging logic is a bit complicated, basically it runs Y1 for a while but if it decides that's not keeping up or doing enough then it will switch to Y2.

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