What Should You Set Your Thermostat to When You Leave for Vacation?

Leaving your New Hampshire home for a summer vacation? Before you pack the car, there is one setting you should not ignore:

Your thermostat.

A lot of homeowners either turn the AC completely off to save money, or leave it set at their normal comfort temperature. Both can cause problems.

The better option for most NH homes is simple:

Set your thermostat to around 80°F to 82°F while you are away.

That range helps reduce energy use while still allowing your air conditioning system to control indoor humidity.

Why You Should Not Turn the AC Completely Off

In New Hampshire, summer heat is only part of the issue. The bigger concern is often humidity.

When a home is closed up for several days, warm humid air can build inside. That moisture can settle into:

• Drywall
• Wood framing
• Furniture
• Carpets
• Closets
• Basements
• Crawl spaces
• Rooms with poor airflow

Once indoor humidity gets too high, your home becomes more vulnerable to musty odors, mold growth, warped wood, and general moisture damage.

Even if the house is empty, it still needs some climate control.

Why 80°F to 82°F Usually Works Well

Setting the thermostat higher than usual helps your system run less, which saves energy. But keeping it on allows the AC to cycle occasionally and remove moisture from the air.

That balance matters.

A vacation setting of 80°F to 82°F can help:

• Lower cooling costs while you are gone
• Reduce unnecessary strain on the AC system
• Keep indoor humidity under better control
• Protect wood, drywall, and stored belongings
• Avoid returning to a hot, damp, musty house

For most New Hampshire homes, this is a smart middle ground between comfort, savings, and property protection.

The Real Goal: Control Humidity

Your thermostat temperature matters, but humidity is the bigger story.

As a general rule, homeowners should try to keep indoor humidity below 60% when possible. Once humidity stays above that level for too long, mold and mildew are more likely to become a problem.

This is especially important in NH homes with:

• Finished basements
• Older insulation
• Crawl spaces
• Poor attic ventilation
• Rooms over garages
• Older ductwork
• Limited air circulation
• Lake homes or seasonal properties
• Homes surrounded by heavy shade or trees

If your home tends to feel damp even when the AC is running, your system may not be removing moisture effectively.

Smart Thermostats Can Help While You Are Away

A smart thermostat is one of the easiest upgrades for homeowners who travel often.

With a smart thermostat, you can:

• Check your home temperature remotely
• Adjust the thermostat from your phone
• Receive alerts if temperatures get too high
• Use humidity-control features
• Prepare the house before you return

Some smart thermostats also have features that use the AC system to help reduce humidity. This can be helpful during long stretches of muggy New Hampshire weather.

Do You Have Pets at Home?

If pets are staying in the house, do not treat the thermostat like an empty-home setting.

For dogs, cats, senior pets, or pets with health concerns, you may need a cooler indoor temperature than 80°F to 82°F.

Before leaving, consider:

• Your pet’s age and health
• Whether rooms get direct sun
• Whether there is good airflow
• How warm the upstairs gets
• Whether someone will be checking in daily

When pets are involved, comfort and safety come before energy savings.

Quick Vacation Checklist for NH Homeowners

Before leaving for vacation, take a few minutes to prepare your home.

Set the thermostat to 80°F to 82°F.
This keeps the AC active without cooling the house like someone is home.

Replace or check the air filter.
A dirty filter can restrict airflow and make the system work harder.

Close blinds and curtains.
This helps reduce heat gain from direct sunlight.

Keep interior doors open.
This allows air to move more evenly through the home.

Make sure vents are not blocked.
Furniture, rugs, or curtains can reduce airflow.

Check basement humidity.
If your basement already feels damp, you may need a dehumidifier.

Unplug nonessential electronics.
This reduces standby power use and extra heat.

Make sure windows are locked and sealed.
Warm, humid air leaking into the house makes the AC work harder.

When to Call a Professional Before You Leave

Your AC should not struggle to maintain a reasonable vacation setting. If something already seems off, it is better to handle it before you are away.

Call for service if you notice:

• Weak airflow
• Uneven cooling
• Musty smells
• Short AC cycles
• High indoor humidity
• Water around the indoor unit
• Ice on the AC system
• Unusual noises
• Rising energy bills
• A thermostat that does not seem accurate

These signs may point to airflow problems, a dirty coil, refrigerant issues, duct leakage, or an oversized system that cools quickly but does not remove enough humidity.

Do Not Forget About Older NH Homes

Many New Hampshire homes were not built with modern cooling in mind. Older colonials, capes, farmhouses, lake homes, and homes with additions can have uneven cooling and humidity problems.

A thermostat setting that works in one room may not protect the whole house.

For example, the downstairs may stay comfortable while upstairs bedrooms or finished attic spaces become hot and humid. Basements may stay cool but damp. Rooms over garages may trap heat. Additions may have weak airflow.

That is why a quick HVAC check can be valuable before a long summer trip.

The Bottom Line

For most New Hampshire homeowners leaving for summer vacation, the best thermostat setting is usually:

80°F to 82°F

That setting helps save energy without letting your home become hot, humid, and vulnerable to moisture problems.

Before you leave, check your filter, close blinds, keep air moving, and make sure your AC system is working properly.

If your home has humidity issues, uneven cooling, or an AC system that runs poorly, Al Terry Plumbing, Heating, HVAC & Electrical can help you get it checked before vacation season.

A little preparation now can help you come home to a cooler, drier, healthier house.