Whole-home humidifiers for New Hampshire homes
New Hampshire winters pull the moisture right out of the air in your house, and your heating system doesn't add any back. That's what leads to the dry skin, bloody noses, and static shocks that show up every year once the furnace kicks on. A whole-home humidifier ties directly into your existing heating system so your entire house stays comfortable, without a single portable unit to refill.
Our Specialists have installed and maintained whole-home humidifiers across the Manchester area since 1987. Over the years, Aprilaire has become our go-to recommendation; it's reliable, well-stocked locally, and built to hold up in New Hampshire homes.
Why GSMS installs Aprilaire
We're a Lennox Premier Dealer, and even Lennox's own Healthy Climate humidifiers are built on Aprilaire's design. So we go straight to the source. A few reasons why:
- It's readily stocked. Every parts vendor in our area carries Aprilaire, so replacement parts are never a delay.
- It's built to resist mold and mildew. Older humidifier designs used a spinning wheel that was nearly impossible to keep clean. Aprilaire's pad design is a honeycomb filter that gets replaced each year, not scrubbed.
- It performs consistently. We don't get callbacks on these units. They work the way they're supposed to, season after season.
Whole-Home Humidifier FAQs
We install Aprilaire exclusively. It's the same design Lennox uses in its Healthy Climate product line, and we've found it to be the most reliable, best-stocked option for New Hampshire homes.
A bypass humidifier uses your furnace's heat to convert water into vapor and needs no electrical hookup. A steam humidifier generates its own vapor and needs a dedicated outlet. The right choice usually comes down to your home's square footage. See our full comparison.
No. Whole-home humidifiers require a forced-air duct system to distribute moisture through your home.
We recommend 35 to 45 percent for most NH homes. The 800LC's automatic dual-sensor control reads outdoor temperature and adjusts on its own, so for normal trips and weekends away, it's best to set it once and let it run. If you're leaving for an extended stretch, like heading south for the winter, that's a different conversation, worth asking your Specialist about at your next visit.
Once a year. That visit replaces the water panel and confirms your system is set for the season.
Pricing depends on your home's electrical setup and ductwork, but visit our pricing page for current bypass and steam installed pricing.
Bypass vs. steam humidifiers: which one fits your home
Not every home gets the same humidifier. Square footage is usually what decides it.
| Factor | Aprilaire 620 Bypass | Aprilaire 800LC Steam |
|---|---|---|
| Best for | Most homes | Larger homes, or homes needing more humidity output |
| Capacity | Up to 18 gallons/day | Higher output than bypass |
| Electrical needs | None | Dedicated 120-volt outlet |
| Water compatibility | Standard water panel | Low-conductivity electrodes, built for well or mineral-heavy water |
| Control | Standard humidistat | Digital automatic humidistat with dual sensors (indoor humidity + outdoor temp) |
| Cost | Lower | Higher |
Aprilaire 620 bypass humidifier
The Aprilaire 620 pulls warm air from your ductwork through a water panel to add moisture; no electrical hookup is required. It's rated for up to 18 gallons of moisture per day, uses a one-piece disposable water panel for fast annual service, and includes adjustable damper positions to fine-tune airflow. This is the right fit for most homes and is the lower-cost option.
Aprilaire 800LC steam humidifier
The Aprilaire 800LC generates its own moisture with a dedicated steam nozzle and requires a dedicated electrical outlet. It's built with low-conductivity electrodes specifically for homes on well water or with mineral-heavy water, and it's the only steam model we install now, per Aprilaire's own recommendation for homes with water quality concerns. It includes a digital automatic humidistat with dual sensors that read both indoor humidity and outdoor temperature, so it adjusts output on its own rather than running on a flat percentage. These are typically used for larger homes or homes that need more humidity output than a bypass system can deliver.
If hard water or mineral content is a concern in your home, our water quality services team can take a look at that too.
For a deeper side-by-side, read our full breakdown: Steam vs. bypass humidifiers: which one is right for your home?
What installation looks like
Both humidifier types are for forced-air heating systems only, they can't be added to boilers, mini-splits, or other non-ducted systems. Here's what our Specialists do on install day:
- Mount the unit, usually on the return side of your ductwork.
- Connect the ductwork. On a bypass system, this means tying in the bypass duct that pulls warm air across the water panel. On a steam system, the steam nozzle installs directly into the ductwork instead.
- Run the water line with a dedicated shutoff valve. A lot of humidifiers come with a piercing fitting that punctures your copper piping, but those are notorious for leaking over time. We always cut in a proper shutoff valve instead.
- Connect to hot water whenever possible, since a bypass humidifier needs heat to convert water to vapor. If your home has a tankless water heater, we'll connect to cold water instead, since tankless units usually won't sense the low flow rate a humidifier needs.
- Wire the controls. If you have a Lennox S40 thermostat, we integrate directly into it for the most precise control. Otherwise, we install a dedicated humidistat, or connect into a compatible Ecobee Premium thermostat.
- Test everything and walk you through it before we leave.
Bypass installations typically take a couple of hours. Steam installations take a bit longer, since they also require a dedicated electrical outlet.
A note for steam humidifiers in zoned systems: steam units release a larger amount of moisture into the ductwork than bypass units, so it's important that airflow keeps moving even when only one zone is calling for heat. Aprilaire makes an air pressure sensor that monitors this and automatically shuts the humidifier off if too much moisture is building up in the ductwork, one of the reasons proper zoned-system sizing matters on a steam install.
Keeping it running: maintenance and common issues
Whole-home humidifiers need annual maintenance, whether that's your only visit of the year or part of your GSMS Home Club membership. That visit includes replacing the water panel (or the carbon cell and UVC lamp, on air purifier add-ons) and confirming your unit is set for the season, since bypass units have a damper that needs to be switched between summer and winter.
If your humidifier stops working, the most common causes are:
- The seasonal damper is still set to summer. An easy fix, and one our Home Club visits catch automatically.
- A failed solenoid valve, the small valve that controls water flow into the unit. This usually needs a service visit.
- A bad humidistat, meaning the unit isn't getting the signal to turn on at all.
- A failed solenoid valve or a blocked orifice, the small components that control water flow into the unit. This usually needs a service visit.
What affects the price
Both the 620 bypass and 800LC steam humidifiers are typically offered at a flat installed price. Two things can change that:
- Electrical requirements. Steam humidifiers need a dedicated 120-volt outlet; if your home doesn't have one nearby, that adds to the job.
- Ductwork layout. Every home's duct system is a little different, and that affects install time.
Is a whole-home humidifier right for your home?
Most people call us because their existing humidifier finally broke and they know they need a new one, or because they've never had one and didn't realize it was an option until we mentioned it during a heating visit. Common reasons NH homeowners add one:
- Dry skin, bloody noses, and static shocks all winter
- Hardwood floors or wood furniture and heirlooms that need consistent humidity to avoid cracking
- Replacing multiple portable humidifiers around the house with one whole-home system
If any of that sounds familiar, our Specialists can help you figure out whether a bypass or steam humidifier is the right fit for your home.
