How to Run Propane Line to Modine 45k Heater: A Comprehensive DIY Guide

Running a propane line to a Modine 45k heater requires careful consideration of various factors, including pipe size, regulator type, and installation techniques. This comprehensive guide will provide you with the necessary information and a step-by-step DIY approach to ensure a successful and safe installation.

Pipe Size and Material Considerations

When installing a propane line for a Modine 45k heater, the recommended pipe size is either 3/4″ or 1″ in diameter. The choice between these two sizes depends on the length of the run and the number of appliances connected to the same line. Using a larger pipe size ensures adequate gas flow and reduces pressure drop.

The most common materials used for gas lines are:

  1. Black Iron Pipe: The traditional choice for gas lines due to its durability and resistance to corrosion. Black iron pipes are available in various schedules (40, 80, etc.) with different wall thicknesses.
  2. Copper Pipe: Also a suitable option, but more expensive than black iron. Copper pipes are available in different types, such as Type L and Type M, with varying wall thicknesses.
  3. PEX (Cross-Linked Polyethylene): A flexible plastic tubing that’s easier to install than metal pipes. However, PEX is not as commonly used for gas lines as black iron or copper.

When selecting the pipe material, consider factors such as local building codes, the environment, and the ease of installation.

Propane Regulator Type and Specifications

A propane regulator is essential to reduce the pressure from the tank to the appropriate level for the Modine 45k heater. For this application, you’ll need a two-stage regulator that provides a constant output pressure regardless of the tank pressure or changes in elevation.

The first stage of the regulator reduces the pressure from the tank (typically 200 psi) to an intermediate pressure (10-15 psi). The second stage further reduces the pressure to the working pressure required by the Modine 45k heater, which is usually 11 inches of water column or 0.4 psi.

It’s important to use a regulator that is specifically designed for propane and rated for the appropriate BTU capacity of the heater.

Step-by-Step Installation Techniques

  1. Sizing the Pipe: To determine the required pipe size, you’ll need to calculate the total connected load (in BTUs) and the length of the run. Use the following formula to calculate the pipe size:

Pipe Size (inches) = (Total Connected Load in BTUs / 100,000) ^ 0.53 x (Length of Run in Feet / 100) ^ 0.53

  1. Installing the Pipe: Begin by measuring and cutting the pipe to the desired length. If using black iron or copper pipes, use a pipe threader to cut threads on the ends of the pipe. For PEX, use the appropriate connectors and tools to make the connections.

  2. Connecting the Pipe to the Heater: Follow the manufacturer’s instructions for connecting the gas line to the Modine 45k heater. This typically involves attaching a flexible gas connector to the heater and then connecting the other end to the gas line using a flare fitting or a compression fitting.

  3. Installing the Regulator: Mount the two-stage propane regulator on a wall or post near the tank and connect it to the tank using a flexible gas connector. Connect the outlet of the regulator to the gas line using a flare fitting or a compression fitting.

  4. Testing the System: After completing the installation, test the system for leaks using a soap solution. Apply the solution to all connections and look for bubbles, which indicate a leak. Tighten any leaking connections and retest until no leaks are detected.

Technical Specifications

  • Pipe Size: 3/4″ or 1″
  • Pipe Material: Black iron, copper, or PEX
  • Regulator Type: Two-stage propane regulator
  • Regulator Outlet Pressure: 11 inches of water column or 0.4 psi

DIY Guide Summary

  1. Calculate the pipe size and material based on the total connected load and the length of the run.
  2. Install the pipe using the appropriate connectors and tools.
  3. Connect the pipe to the Modine 45k heater following the manufacturer’s instructions.
  4. Install the two-stage propane regulator near the tank and connect it to the tank and the gas line.
  5. Test the system for leaks and tighten any leaking connections.

By following this comprehensive guide, you can successfully run a propane line to your Modine 45k heater, ensuring a safe and efficient heating solution for your space.


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