Preparing heating equipment for winter with preventive maintenance


As the days grow shorter and temperatures drop, heating systems are finally turned on after a long period of disuse. This time of year signals the important task of evaluating a building’s energy system to ensure it is equipped to deliver heat efficiently and safely.

Building owners must establish a preventive maintenance program with their energy provider to maintain efficient energy delivery, avoid equipment failures, reduce energy costs, and ensure the long-term sustainability of a commercial property.

Why preventive maintenance is critical

The winter season is a key time to evaluate the equipment used in buildings connected to district energy systems. Taking preventive measures with a building’s heating equipment before the winter season and low temperatures begin in earnest can help to:

  • Improve equipment reliability and function
  • Reduce energy consumption, greenhouse gas emissions, and operational costs
  • Prevent unplanned costs, maintenance, and even system downtime
  • Enhance safety for employees and building occupants

How to prepare heating equipment for cold weather

Partnering with our customers, Vicinity’s team tailors our preventive maintenance approach to the unique needs of each building.Preventive maintenance activities can be done any time but are typically conducted in preparation for the winter and the summer to prepare for peak loads due to temperature changes

Depending on the building’s system, our team can isolate a maintenance issue or conduct a small shutdown event to repair equipment. Ahead of low temperatures, buildings can also test their heating system during off hours or weekends to identify any problems with climate control or local area flow control.

However, several elements of district energy systems require inspection every year or more. Let’s dive into the most critical components buildings should focus on when preparing for the heating season.

Steam trap inspections

Steam traps collect condensate to prevent corrosion caused by built-up moisture and ensure that high-quality, dry steam flows through the steam system. Steam traps also block the escape of live steam, minimizing energy waste. Typically done between November and March, steam trap surveys help ensure the efficient delivery of district energy.

A Vicinity technician conducts the steam trap inspection using an ultrasonic digital detector. The process involves locating, identifying, tagging, and periodically testing the performance of the steam trap. If it is the first survey, the technician tags and catalogs each trap for future surveys.

Failed traps can allow large amounts of steam to pass through the equipment before giving up its thermal energy content. Failed traps can lead to water hammers, which damage the building’s system and produce undesirable noise.

Pressure Regulating Valves (PRVs)

Pressure regulating valves (PRVs) are designed to reduce incoming steam pressure to ensure safe steam distribution. While typically done in the summer, testing pressure regulating valves can be done at any time to prepare for the winter season.

Vicinity’s team will typically identify the PRV’s make, model, size, and serial number. They will then test the valve for leaks, clean orifices, test the gauging, and set it to the desired system pressure.

Testing PRVs is important because failed PRVs may cause system over-pressurization and relief valves to release steam into the atmosphere. The PRV can also improperly cycle open and closed, both oversupplying and then starving the downstream equipment of steam. The inspection will include inspecting the PRV operating mechanism (pneumatic, hydraulic, or motor operated).

Heat exchanger and water samples

A heat exchanger is a system that transfers heat between a source and a working fluid. District energy systems transfer heat from the hot water in the district heating system to the cold water in an individual building’s heating system.

To ensure that heat exchangers function properly, Vicinity’s team takes water samples from the heat exchanger and tests the water for conductivity. This test helps ensure that tube bundles are not leaking and that city water is not entering the system through such leaks.

Vicinity’s team also drains cooling tower heaters during cold weather. When temperatures are expected to be below 20 degrees F for an extended period, the cooling tower basin heaters are drained below the building roof level, the basin heater is turned off, and space heaters are turned on as applicable. Our team also works to adjust glycol or other antifreeze concentrations throughout the cooling system, as required. 

Steam pipe

Before the winter season, it’s standard to visually inspect steam piping. Vicinity’s team typically checks for leaking joints, watermarks, insulation, and corrosion on the pipes.

This ensures safe, reliable steam delivery into the building and reduces the opportunity for steam to leak into the connected building.

Condensate return line

A visual inspection of the building’s condensate return line is done ahead of the winter season to check for leaks and corrosion. A condensate return system collects condensate from different points in the system and returns it to the boiler to save energy. This inspection involves checking the condensate pump seals for leaks and vent pipes for vapor emissions. Proper insulation and plugging penetrations is key to preventing freeze ups.

This inspection is done to avoid condensate water spills and ensure proper evacuation of condensate from system lines, allowing steam-operated equipment to function correctly. The test can also help identify any leaking steam traps in the system.

Mechanical room hot water loop

In the mechanical room of a building, Vicinity’s team inspects all piping, inlet/outlet temperatures, and pressures on heat exchangers and mechanical pumps.

This inspection confirms the adequate operation of key energy transfer equipment, such as heat exchangers, which supply building heat, hot water, and other process loads. The general condition and function testing of space heaters and heat tracing is important to note as well.

Winter preparedness checklist

Vicinity’s facilities take extensive measures to prepare for the winter weather before the month of November to make sure our teams are prepared for any extreme weather or cold-related emergency that comes up.

There are steps that every building should take, however, to ensure winter preparedness:

  • Designate a ‘weather watcher’ to monitor weather conditions.
  • Train your team on how to properly remove snow from roofs, roads, and equipment, staff according to needs.
  • Gather emergency supplies, including steam hoses for thawing frozen lines, portable heaters, antifreeze supplies for cooling systems, shovels, warm clothing and hand protection.
  • Keep all fire-protection-related equipment free of snow and ice for easy access.
  • Check wet and dry sprinkler systems and keep them clear of snow and ice.
  • Prepare snow removal equipment.
  • Make sure fixed and portable heaters are working and have appropriate fuel levels.
  • Ensure the building envelope is in good condition and close unnecessary openings like doors, windows, and piping penetrations.

Vicinity’s experts are here to help

Taking proactive steps to maintain your building’s energy systems can lead to significant benefits. From lower energy bills to a reduced carbon footprint, the effort invested in preparing your facility for winter pays off. Vicinity’s energy experts are here to help with all your energy needs. Give our energy experts a call to:

  • Work on repairs
  • Submit quotes before the coming heating season
  • Get help preparing your budgets for next year
  • Schedule a site visit to get preventive maintenance assessments from our team

Learn more about our electrification plan in our white paper.

Vicinity Energy White Paper - Revolutionizing Urban Sustainability

Tricia Keegan

Based in Boston, MA, Tricia helps lead our team to partner with clients and operations staff to assure reliable, efficient operations. She writes about topics related to district energy operations, preventive maintenance, and more.