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Rheem Water Heater Vacation Mode – Meaning, Causes & Fix

RheemWater HeaterUpdated 2026-10-04

Vacation Mode on a Rheem gas or electric water heater is an energy-saving setting that lowers the water heater's thermostat setpoint to a minimal standby temperature (typically around 50°F / 10°C, or the lowest setting that prevents freezing) while you're away from home for an extended period. Rather than maintaining the tank at the normal 120°F operating temperature, the water heater drops to a low standby to save energy while still protecting the tank and plumbing from freezing in cold weather. On Rheem's gas and electric tank models, Vacation Mode is a deliberate user setting; on Rheem's tankless (EcoNet and Performance) models, the system may also enter a similar low-fire standby automatically. This guide explains what Vacation Mode does, why it appears, and how to exit or use it correctly. For related HVAC system standby behaviors, see our Trane Thermostat Waiting Message guide and our Carrier Thermostat Offline guide.

Quick Answer

What it means

The water heater has been set to a low-temperature standby mode that minimizes energy use while protecting the tank from freezing, intended for use while you're away from home.

Severity

Low

Can you fix it yourself?

Yes — Vacation Mode is a deliberate user setting; exiting it simply requires adjusting the thermostat setpoint back to the normal operating temperature.

Call a technician when

A technician is rarely needed for Vacation Mode itself — call a plumber only if the water heater won't return to normal operation after exiting Vacation Mode, which may indicate a faulty gas valve or thermostat.

What Does Vacation Mode Mean?

Rheem water heaters offer a Vacation Mode (sometimes labeled "VAC" on the thermostat dial or electronic display) as an energy-saving feature for extended absences. When engaged, the water heater's thermostat setpoint drops from the normal operating temperature (typically 120°F / 49°C) to a minimal standby temperature — just high enough to prevent the tank and connected plumbing from freezing in cold weather, but well below the temperature needed for normal hot water use.

Vacation Mode serves two purposes:

1. Energy savings: Maintaining a tank of water at 120°F while you're away for a week or more wastes significant energy; dropping to a low standby saves that energy without emptying the tank. 2. Freeze protection: In cold climates, a water heater left fully off while the home is unheated can freeze and burst; Vacation Mode keeps the tank above freezing.

Common reasons Vacation Mode appears or behaves unexpectedly include:

1. Deliberate user setting: The homeowner set Vacation Mode before leaving and forgot to turn it back off — the most common scenario. 2. Accidental engagement: The thermostat dial was bumped to VAC, or the electronic control was set to Vacation by mistake. 3. No hot water on return: The water heater is still in Vacation Mode after the homeowner returns, producing lukewarm or cold water. 4. Tankless model auto-standby: Some Rheem tankless models enter a low-fire standby after a period of no demand, which is similar to but distinct from the user-set Vacation Mode. 5. Frozen or cold water despite Vacation Mode: In very cold weather, even Vacation Mode's standby temperature may not be enough if the home's heat is also off — the tank and plumbing can still freeze.

This standby-setting behavior is conceptually similar to the Trane thermostat Waiting message, which is a deliberate, intentional delay rather than a fault — Vacation Mode is a deliberate setting, not an error.

What Causes This Error?

  • Deliberate user setting — the homeowner set Vacation Mode before leaving and forgot to turn it back off
  • Accidental engagement — the thermostat dial was bumped to VAC, or the electronic control was set to Vacation by mistake
  • No hot water on return — the water heater is still in Vacation Mode after the homeowner returns, producing lukewarm or cold water
  • Tankless model auto-standby — some Rheem tankless models enter a low-fire standby after a period of no demand
  • Frozen or cold water despite Vacation Mode — in very cold weather with the home's heat also off, the standby temperature may not prevent freezing
  • Faulty thermostat or gas valve failing to resume normal operation after Vacation Mode is exited
  • EcoNet app remote setting left in Vacation Mode from a previous trip

How to Fix Vacation Mode

  1. 1

    Confirm the water heater is in Vacation Mode. On gas models with a dial thermostat, check whether the dial is set to VAC or the lowest setting. On electronic (EcoNet or Performance) models, check the display for a VAC icon or a Vacation Mode indicator in the settings menu.

  2. 2

    Exit Vacation Mode by resetting the thermostat to the normal operating temperature. On gas dial models, turn the dial from VAC to the desired setting (typically the triangle marker or a specific temperature). On electronic models, navigate the menu to exit Vacation Mode and set the tank temperature to 120°F (49°C).

  3. 3

    Allow time for the tank to reheat. After exiting Vacation Mode, the water heater will take 30-60 minutes (for a tank model) to bring the tank back up to the normal operating temperature. Run a hot tap briefly to confirm hot water is being produced after the recovery period.

  4. 4

    Check the EcoNet app if you use remote control. If you control the water heater via the Rheem EcoNet app, open the app and confirm the water heater isn't still set to Vacation Mode from a previous trip — the app setting overrides the local control.

  5. 5

    Verify freeze protection in cold weather. If you're leaving the home unheated in cold weather, confirm the Vacation Mode standby temperature (or a minimum thermostat setting) is sufficient to keep the tank and plumbing above freezing. In very cold climates, draining the tank may be safer than relying on Vacation Mode.

  6. 6

    Call a plumber if the water heater won't return to normal operation. If the water heater fails to produce hot water after exiting Vacation Mode and allowing recovery time, or if the thermostat won't respond to setpoint changes, call a licensed plumber — the gas valve (gas models) or thermostat/element (electric models) has likely failed and needs replacement.

When to Call a Professional

Vacation Mode itself rarely requires a technician — it's a deliberate setting and exiting it simply requires resetting the thermostat. Call a licensed plumber only if the water heater fails to produce hot water after exiting Vacation Mode and allowing a 30-60 minute recovery period, which typically indicates a failed gas valve (gas models, $200-$400 including parts and labor) or a failed thermostat or heating element (electric models, $150-$350). In very cold climates, consider draining the tank entirely for extended winter absences rather than relying on Vacation Mode freeze protection.

Can You Still Use the Device?

A Rheem water heater in Vacation Mode produces lukewarm or cold water by design — the tank is held at a low standby temperature, not the normal 120°F operating temperature. Normal hot water resumes within 30-60 minutes of exiting Vacation Mode (the tank recovery time). The water heater is fully functional in Vacation Mode; it's simply set to save energy during an absence, and normal operation resumes as soon as the thermostat is reset to the operating temperature.

Official Resources

Disclaimer: This article is for informational purposes only and does not constitute professional repair advice. CodeExplain is not affiliated with Rheem or any other brand mentioned. Always consult a qualified technician for complex repairs.