Hooking Up A Furnace Thermostat In Your Camper, Simplified

Hooking up a furnace thermostat in a camper can be a simple task if you have the right tools and knowledge. In this article, we will guide you through the process of selecting the correct replacement thermostat, understanding the wiring, and installing it in your camper. We will also offer some tips and tricks to make the process easier and provide suggestions for troubleshooting common issues.

Understanding the wiring

Identify the Type of HVAC System

Before you begin, it's important to identify the type of heating, ventilation, and air conditioning (HVAC) system you have in your camper. This is essential because different systems may have different wiring configurations. The most common types include gas furnace and air conditioner split systems, air conditioner/oil furnace combinations, stand-alone air conditioners, and more. Knowing your specific system will help you select the appropriate replacement thermostat and understand its wiring requirements.

Turn Off Power and Remove Old Thermostat

Once you've identified your system, turn off the power to your HVAC system at the main breaker box. This is a crucial safety step to prevent any electrical hazards. Then, carefully remove the old thermostat from the wall. In some cases, it may be held in place with screws, while in others, you may need to gently pop it off. Be cautious not to damage the wall or the wiring during this process.

Label and Note Existing Wires

Before disconnecting any wires, take a photo or make detailed notes of the existing wiring configuration. Label each wire with its corresponding terminal, colour, and function. This step is crucial for understanding the wiring setup and ensuring proper reconnection. Thermostats typically use a standard colour code for wires, which can help you identify their purposes:

• Red wire (Rc and Rh): These wires are the power source for the thermostat. If your thermostat controls both heating and cooling, you'll have both Rc and Rh red wires.
• White wire (W): The white wire is connected to your heating system.
• Yellow wire (Y): The yellow wire connects to your air conditioning compressor.
• Green wire (G): This wire is responsible for the fan operation.
• Blue wire (C): The blue wire, also known as the common or c-wire, provides continuous power to smart and programmable thermostats.

Install New Thermostat and Connect Wires

After understanding the wiring configuration, it's time to install the new thermostat. Mount the new thermostat sub-base using the same holes as the old one, ensuring a secure fit. Then, connect the wires from the old thermostat to the designated terminals on the new thermostat, following the industry standard colour codes or your previous notes. Double-check all connections for accuracy.

Restore Power and Test the System

Once the wiring is complete, restore power to the HVAC system at the main breaker. Test the system to ensure proper operation, including testing the furnace for heating, the air conditioner for cooling, and the fan for manual operation. Allow for any built-in time delays in the system before concluding your tests.

Remember, always refer to the manufacturer's instructions for your specific furnace thermostat model, as there may be unique considerations or variations in wiring requirements. If you're unsure or uncomfortable at any point during the process, don't hesitate to consult a professional electrician for assistance.

Turning off the power

• Turn your existing thermostat to the OFF position.
• Wait for any cooling or heating to stop. This is important to ensure that the system is not actively running when you proceed to the next step.
• Turn off the power to your HVAC system at the main breaker box. Locate the electrical panel where the circuit breakers are and turn off the power. For split systems with separate breakers for air conditioning and heating, ensure that you turn off both breakers.
• Remove the faceplate or control panel of your thermostat. Refer to the user's manual for specific instructions on how to safely remove the faceplate without damaging the wires or the thermostat.
• At this point, you have successfully turned off the power to the thermostat and can proceed with the next steps of the installation process, such as labelling and disconnecting the wires.

Remember to exercise caution when working with electrical systems. If you are unsure or uncomfortable at any point, it is best to consult a professional electrician for assistance. Safety should always be the top priority when working with electrical systems.

Removing the old thermostat

Turn Off the Power

Locate your camper's electrical panel and turn off the power to the furnace. It is crucial to ensure that the power is off before proceeding with any electrical work.

Remove the Old Thermostat

Gently pull the old thermostat to detach it from its sub-base. In some cases, it may be held in place with screws, so be sure to check before applying force. If you have the original instructions for the thermostat, refer to them for guidance on disassembling it. Be cautious not to pull the sub-base off the wall.

Label the Wires

Once the thermostat is removed, you will see a set of wires connected to terminals. Label each wire with small pieces of tape or tags, noting their respective terminal connections. Taking a clear picture of the wiring setup can also be helpful for reference.

Disconnect the Wires

After labelling, carefully disconnect the wires from the old thermostat. Be mindful to avoid letting the wires slip into the wall. You can use a pen or pencil to wrap one of the wires around and prevent them from falling inside.

Remove the Old Sub-base

With the wires disconnected, you can now remove the old sub-base from the wall. Be cautious not to damage the wires during this process.

By following these steps, you will have successfully removed the old thermostat, preparing you for the next stage of installing the new furnace thermostat in your camper. Remember to work carefully and refer to the instructions provided with your new thermostat for any additional steps or variations.

Labelling the wires

• Turn Off the Power: Before beginning any work on the thermostat, it is imperative to ensure your safety by turning off the power. Locate the electrical panel or the main breaker box and turn off the power to the air conditioner or furnace. For split systems, you will typically find two circuit breakers, one each for the air conditioning and heating system. Make sure to flip both of these breakers to the off position.
• Remove the Old Thermostat: Gently remove the old thermostat from the sub-base. In some cases, it may be held in place with screws, while other times it can be detached by applying a little force. Refer to the original installation instructions, if available, for guidance on disassembling the thermostat. Be cautious not to pull the sub-base off the wall while removing the thermostat.
• Identify and Label the Wires: With the main thermostat separated from the sub-base, you will now see the wires connected to the terminals. It is important to identify and label these wires correctly. You can refer to a thermostat colour code chart to understand the purpose of each wire. Take a picture of the wiring scheme or make notes on a piece of paper. Label each wire with painter's tape and a permanent marker, ensuring you note the colour and the terminal it is connected to.
• Disconnect the Wires: Once you have comprehensively labelled the wires, it is now safe to disconnect them from the old thermostat. Be careful not to let the wires slip into the wall. You can use a pen or pencil to wrap one of the wires around, preventing it from falling into the wall cavity.
• Prepare for the New Thermostat: After removing the old sub-base, you will need to prepare the wall for the new thermostat. Use the same holes that were used for the previous thermostat to mount the new sub-base. Secure it tightly, ensuring it is firmly in place.
• Reconnect the Wires: Refer to your notes or the picture you took of the old wiring scheme. Reconnect the wires to the designated terminals on the new thermostat, matching the colours to the correct terminals. You can also refer to the installation guide that came with the new thermostat for further instructions if needed.
• Install the New Thermostat: Carefully attach the new thermostat onto the sub-base, following the manufacturer's instructions. Pay attention to aligning the pins correctly to avoid bending them.
• Restore Power and Test: After installing the new thermostat, restore power to the system and test its functionality. Test the furnace for heating, the air conditioner for cooling, and the fan for manual operation. Ensure that each component operates as expected, keeping in mind that there may be built-in time delays in the thermostat and HVAC system.

By following these steps, you will effectively label the wires when hooking up a furnace thermostat in your camper, ensuring a smooth and safe installation process.

Installing the new thermostat

Firstly, turn off your existing thermostat and ensure any cooling or heating has stopped. Then, turn off the power to your HVAC system at the main breaker box. Remove the faceplate or control panel of your thermostat according to the user's manual to reveal the wires. Do not remove the rest of the thermostat from the wall or detach the wiring.

Now, locate the common wire. Look for a wire connected to a terminal labelled with a 'C' on the thermostat. If you have one, that's your c-wire, and you're ready for general installation. The common wire is responsible for delivering constant power to your thermostat. For programmable and smart thermostats, c-wires are required for setting a heating or cooling schedule. While some units can run without a c-wire, most brands suggest having one for optimal function. If you don't have a c-wire, check the area behind the thermostat to see if one was tucked into the wall by an electrician or installer. Many older thermostats did not need c-wires but they were available for use.

Next, identify and label the wiring in your existing thermostat before disconnecting the wires. Take a picture of your current wiring scheme and check if they match the industry standard. If they do, you can use this as your guide to connect your new thermostat. If not, make your own list and label each wire with a strip of painter's tape and a permanent marker. Disconnect the wires and the corresponding mounting screws. The back plate from your thermostat should now come free. Tape the wires to the wall with painter's tape so they don't fall into the wall while you prepare your new thermostat.

Place the plate of your new thermostat against the wall where it will be located. Check the plate with a level and mark the screw holes with a pencil. If applicable, drill guide holes before adding anchors to the wall. Pull the wires through the opening of the thermostat's backplate. Attach the back plate to the wall with the provided screws. Check to make sure the thermostat is secure.

Reconnect the wires according to the industry-standard colour codes or your unit-specific notes. Double-check that they're connected in the right place. If necessary, refer to the photo you took of the old wiring scheme or the instructions that came with the thermostat. Replace the thermostat cover.

Finally, turn the HVAC power back on at the main breaker. Follow the manufacturer's instructions to connect to Wi-Fi and set up user programs.

Frequently asked questions