How To Replace Your Camper's Thermostat Yourself

A camper's thermostat is an essential component of its setup, regulating the interior temperature to keep you warm in winter and cool in summer. While an RV's thermostat is similar to the one in your home, it is not interchangeable. RV thermostats typically operate on 12V DC power, while household thermostats use 24V AC power. However, it is possible to replace your RV thermostat with a household thermostat, provided it is battery-operated and compatible with your RV's make, model, and heating/cooling system.

There are several signs that indicate it's time to replace your RV thermostat, such as a blank display screen, a temperature mismatch, or a continuously running heating or air conditioning system. Before replacing it, you can try resetting the thermostat or checking the batteries and fuse. If these troubleshooting methods don't work, you'll need to install a new thermostat, which typically costs between $20 and $200, depending on its features.

When choosing a new thermostat, you'll need to consider the type of thermostat you want (analog, digital, or programmable), its compatibility with your RV's system, and any special features you may desire, such as Wi-Fi connectivity or zone control.

Thermostat compatibility with your RV

Type of Thermostat

RV thermostats come in different types, including analog, digital, programmable, and smart thermostats. Analog thermostats are simple and reliable, while digital thermostats offer more precise temperature control. Programmable thermostats allow you to schedule temperature changes, and smart thermostats offer remote control via smartphone apps. Choose a type that suits your needs and budget.

Voltage Requirements

RV thermostats typically operate on 12V DC power, while residential thermostats use 24V AC power. Ensure that the replacement thermostat is compatible with your RV's electrical system.

HVAC Equipment Compatibility

When replacing your RV thermostat, it is crucial to ensure compatibility with your existing HVAC (heating, ventilation, and air conditioning) equipment. Check if the new thermostat is designed to work with the specific brand and model of your air conditioners, heat pumps, or furnaces. In many cases, it is recommended to use the same brand of thermostat as your HVAC equipment.

RV Make and Model

The make and model of your RV can also impact thermostat compatibility. Some RVs have unique wiring configurations or specific requirements for thermostat replacement. Consult your RV's manual or seek advice from a certified RV technician to ensure the new thermostat is compatible with your RV's system.

Installation Process

The installation process for a new thermostat can vary depending on the RV's make and model, as well as the type of thermostat being installed. In some cases, it may be a simple plug-and-play replacement, while others may require more complex rewiring. It is recommended to consult a professional or refer to online resources for detailed installation instructions.

Zoning Requirements

If your RV has multiple heating or cooling zones, you may need a thermostat that can control each zone independently. Some thermostats offer zoning features, allowing you to manipulate the temperature in different areas of your RV.

By considering these factors, you can ensure that your new thermostat is compatible with your RV's systems and meets your specific needs.

Thermostat wiring

2-Wire Thermostat Wiring (Furnaces)

The most basic thermostat has 2 wires; usually a red and a white wire. Two-wire thermostat wiring is used for furnaces only and usually doesn’t need a “C” or “Common” wire. That’s why we only need two wires. This is a 2-wire thermostat wiring colour code:

• Red wire for power (24h)
• White wire for heating

• Remove the control panel of the old furnace thermostat.
• Take a note of where the wires go; usually, the red R wire will go to R, and the white wire will go to Rh or W1. You can also take a photo.
• Unscrew the two wires from the terminals.
• Remove the motherboard of the old 2-wire thermostat and put the new 2-wire thermostat in its place.
• Reconnect the red and white wire, tighten down the set screw, and put the control panel back on.
• Test the 2-wire thermostat wiring by turning the furnace on.

3-Wire Thermostat Wiring (Boilers, Heaters)

3-wire thermostats are most commonly used to control the heaters; boilers and hot water heaters in particular. The 3 wires you will find usually have codes R, G, and W.

The difference between 2-wire and 3-wire thermometers is the “G” or green wire that is usually used for fans. In the 3-wire thermostat wiring, the green wire serves as a repurposed C or “Common” wire. Here is the 3-wire thermostat wiring colour code:

• Red wire for power (24V)
• White wire for heating (connected to W or W1 terminal)
• Green wire as a repurposed C wire

• Remove the control panel of the old thermostat.
• Take a picture of the 3 wires. Note the colour – red, white, and green – and the terminals – R, W or W1, G.
• Remove the motherboard of the old thermostat completely, and secure the wires. You don’t want them to hide deep inside the wall.
• Put the new motherboard in the place of the old one, and pull the wires through the 3-wire thermostat.
• Correctly reconnect the wires – red to R, white to W or W1, green to G – and tighten the terminal screws.
• Put on the control panel, and test if your boiler or hot water heater connected to the 3-wire thermometer functions properly.

4-Wire Thermostat Wiring (Heat Pumps, HVAC)

4-wire thermostats have a bit more flexibility. Smart thermostats like Nest and Ecobee thermostats require 4-wire thermostat wiring to function properly.

In addition to heating (2-wire thermostats) and C or fan (3-wire thermostats), 4-wire thermostats include the cooling wire, usually in blue or yellow colour. Here are the wires in 4-wire thermostats with terminal codes and colour codes (also referred to as 4-wire thermostat wiring colour code):

• Red wire for power (24V)
• White wire for heating (connected to W or W1 terminal)
• Green wire for fans
• Blue or yellow wire for cooling (connected to Y)

These thermostats are typical for heat pumps: HVAC devices that can cool and heat. To produce the airflow, a fan is needed (green wire).

• Take the control panel off and expose the wires in the old 4-wire thermostat.
• Take a photo of the wires; you can also label where each one goes, but taking a photo is much easier.
• Take off the motherboard and secure the wires; if you don’t hold them, the four wires will get lost in the wall.
• Screw on the new motherboard, and pull the 4 wires through the hole.
• Reconnect the 4 wires to the appropriate terminals – red to R, white to W or W1, green to G, and blue or yellow to Y – and screw them in place. Pull each wire to make sure that it’s fixed in place.
• Turn on the heat pump or any other HVAC device that connects to the 4-wire thermostat.

5-Wire Thermostat Wiring (Any HVAC Device – Air Conditioners, Heat Pumps, Furnaces, etc.)

5-wire thermostat is basically a 4-wire thermostat with a “C” or “Common” wire. The newer digital thermostats for HVAC devices all require a 24V C wire connection to function. 5-wire thermostats are the most versatile thermostat; they control anything from smart air conditioners, heat pumps, furnaces, and so on.

• Red wire for power (24V)
• White wire for heating (connected to W or W1 terminal)
• Green wire for fans
• Blue or yellow wire for cooling (connected to Y)
• Black wire for “C” or “Common” wire

• Take the control panel off and expose the wires in the old 5-wire thermostat.
• Take a photo of the wires; you can also label where each one goes, but taking a photo is much easier.
• Take off the motherboard and secure the wires; if you don’t hold them, the four wires will get lost in the wall.
• Screw on the new motherboard, and pull the 5 wires through the hole.
• Reconnect the 5 wires to the appropriate terminals – red to R, white to W or W1, green to G, and blue or yellow to Y, black to C – and screw them in place. Pull each wire to make sure that it’s fixed in place.
• Turn on any smart device that connects to the 5-wire thermostat, and try to use the smartphone app or remote control to check if everything works as it should.

These are the basics of thermostat wiring. If you have just a bit of technical skills, you will probably be more than able to DIY thermostat replacement.

Thermostat power sources

Thermostats are an essential part of an RV's setup, helping to maintain a comfortable temperature inside the vehicle. While RV thermostats are designed specifically for this purpose, it is possible to replace them with household thermostats, provided certain conditions are met.

Power Sources

Most household thermostats run on 24 volts of alternating current (AC) power, whereas RV thermostats typically operate on 12 volts of direct current (DC) power. Therefore, a household thermostat will only work in an RV if it is battery-operated, using the internal battery to power the relay and display. If the thermostat is not battery-operated, the RV will not be able to supply the required power, and the thermostat will not function properly.

RV thermostats are usually powered by the furnace wiring. However, some thermostats, such as the Dometic 3106995.032 OEM Thermostat, are analog and do not require electrical power to operate.

Compatibility

In addition to power sources, compatibility is a key consideration when replacing an RV thermostat. The make and model of the RV, as well as the type of heating and cooling system it has, will determine whether a household thermostat can be used as a replacement. Certain RV thermostats must be replaced with the same model due to specific wiring configurations. Additionally, if the RV has a dual-speed air conditioning system, the replacement thermostat must have dual fan speed capability or an additional switch to control the different fan speeds.

Installation

Replacing an RV thermostat with a household thermostat may require some wiring adjustments. Online forums and YouTube tutorials can provide guidance on the installation process, but it is important to ensure that the wiring is connected correctly to avoid damage to the system.

Thermostat types

There are several types of thermostats available for campers and RVs, each with its own advantages and disadvantages. Here is a detailed overview of the different types:

Analog Thermostats

Analog thermostats are the most basic type of thermostats available for campers. They use heat-sensitive metal that bends when the temperature changes, making contact with a switch that activates the heating or cooling mechanism. One of the main advantages of analog thermostats is that they don't require electrical power to operate, making them a budget-friendly option. They are also generally reliable and easy to install. However, they may not be compatible with the newest RV HVAC models, and they may not offer the same level of precision as digital thermostats.

Digital Thermostats

Digital thermostats for campers provide a more modern approach to temperature control. They feature precise digital temperature readouts, allowing users to easily adjust the temperature with the touch of a button. Digital thermostats require electrical power to operate their internal circuitry and display panels, typically drawing power from the furnace wiring. While they offer more precision and convenience than analog thermostats, they may be more expensive and might not be compatible with all RV models.

Programmable Thermostats

Programmable thermostats offer a significant upgrade in terms of functionality. They allow users to pre-program temperature settings, so campers can return to a comfortable environment after a long day of activities. This type of thermostat can help save money by only running the heating or cooling system when needed. Programmable thermostats are an excellent choice for those who want more control over their RV's temperature and want to optimize energy efficiency.

Smart Thermostats

Smart thermostats are the most advanced type available for campers. They offer remote control capabilities, allowing users to monitor and adjust the temperature from anywhere using a smartphone app. These thermostats can also integrate with other "smart home" technologies, such as Amazon Alexa, Google Nest, or Apple Home. While smart thermostats provide unparalleled convenience and flexibility, they typically come with a higher price tag and may require additional wiring or technical knowledge for installation.

Replacing an RV thermostat

When replacing an RV thermostat, it is important to choose a thermostat that is compatible with the RV's make and model, as well as the type of heating and cooling system it has. The most common types of RV thermostats are analog, digital, programmable, and smart thermostats. Analog thermostats are the simplest and most cost-effective, while digital thermostats offer more precise temperature control and are similar to those found in residential homes. Programmable thermostats allow for scheduling heating and cooling changes, and smart thermostats offer modern features like Bluetooth connectivity and remote control via a smartphone app.

The process of replacing an RV thermostat can be summarised as follows:

• Turn off the power supply to the thermostat and/or HVAC system by disconnecting the RV's battery and/or unplugging shore power/generator.
• Remove the old thermostat by taking off the front cover and unscrewing it from its mounting. Take note of how the wires are attached to the old thermostat or take a picture for reference.
• Disconnect the wires from the rear of the old thermostat.
• Unscrew and remove the mounting bracket from the wall.
• Remove the new thermostat from its packaging and skim the user manual for any specific installation instructions.
• Screw the new mounting bracket into place.
• Connect the wires to the new thermostat, following the reference from step 2. Ensure that the wires are securely connected by gently pulling on them.
• Screw the thermostat to the mounting and put the front cover back on.
• Reconnect the power supply to the system and test the new thermostat.

It is important to note that some RVs may have multiple thermostats for different zones or separate heating and cooling systems. In such cases, the replacement process may vary slightly, but the basic steps remain the same. Additionally, it is always recommended to consult a professional or a knowledgeable person for advice and assistance if needed.

Frequently asked questions