How to Perform a Site Walk That Actually Sells BAS Retrofits and Planned Service Agreements

Most building automation opportunities are won or lost long before the proposal is sent. They are won or lost in the site walk.

If the walk is rushed, shallow, or performed by someone who does not really understand HVAC and controls, you get vague scopes, missed issues, and weak proposals. If the walk is structured and technical, you get clear findings, strong business cases, and higher close rates.

This guide walks you through a detailed, repeatable process for site walks that consistently uncover profitable BAS retrofits and planned service agreements. You can turn this into a checklist for your sales and operations teams.

Step 1. Prepare Before You Arrive

A great site walk starts with what you do at your desk, not what you do in the mechanical room.

1.1 Pre-call with the customer

Before the visit, schedule a short discovery call. The purpose is not to sell. It is to clarify scope and expectations.

Ask:

• What problems are you currently experiencing with your HVAC or BAS?
• How are those problems showing up for your occupants or operations team?
• Have there been any major changes to the building in the last 3 to 5 years?
• What systems do you believe are working well, and which are always a headache?
• What is driving this conversation right now: comfort, energy, reliability, compliance, or something else?

Summarize what you heard and repeat it back. These drivers will shape everything you look for during the walk.

1.2 Gather and review documentation

Request:

• Mechanical schedules and floor plans
• Controls submittals and riser diagrams
• Sequences of operation
• BAS network drawings
• Previous commissioning reports
• Existing PSAs or service contracts
• Recent work orders and complaint logs

When you review these, do not just skim. Look for:

• Mismatches between sequence and likely operation
• Old or legacy platforms noted in the submittals
• Critical spaces that require tight control
• Complex systems, such as labs, data centers, or ORs

Make a short list of suspicious systems you want to validate on site.

1.3 Plan the route and logistics

On the call or by email, confirm:

• Where you can park and enter
• Required PPE and safety orientation
• Whether you will have access to the BAS workstation
• Whether IT needs to be involved for BAS access
• Which mechanical rooms, rooftops, and tenant areas you can visit
• Who will accompany you

Plan a basic route: front end first, then central plant, then AHUs and RTUs, then terminal units and representative spaces.

1.4 Prepare tools and forms

At a minimum, bring:

• Tablet or printed data collection sheets
• Flashlight
• Small hand tools for panel access
• Temperature and humidity meter
• CO2 meter for ventilation checks
• Camera or phone with good photo capabilities
• Basic network tester or at least a cable verifier
• PPE: hard hat, safety glasses, gloves, hearing protection as required

Create or use a standardized site walk form broken down by:

• BAS architecture
• Central plant
• Air handlers and RTUs
• Terminal units
• Critical spaces
• PSA opportunities
• Retrofit candidates

This keeps every walk consistent and makes it easier to compare buildings.

Step 2. Start With the BAS Architecture

Always begin with the BAS, not the equipment. The BAS tells you how the building behaves and where to focus.

2.1 Understand the front end

Sit down at the BAS workstation with the operator, if possible.

Confirm:

• System name and version
• Whether the supervisory server is physical or virtual
• How many buildings and subsystems are integrated
• How users log in and what their rights are
• How often the system is backed up and who manages that backup

Ask the operator:

• Are there parts of the system you avoid using because they are confusing or unreliable?
• If something breaks, what do you do first?
• What parts of the system have you given up on?

These comments often point directly to high value retrofit and PSA tasks.

2.2 Review integrations and third party systems

Identify:

• What else is integrated: meters, VFDs, lighting, security, elevators
• Whether these integrations are stable and used, or mostly broken and ignored
• Any custom drivers or gateways that are single points of failure

Note any integrations that are important but flaky. They are strong candidates for retrofit work or ongoing PSA support.

2.3 Map the network

With the riser diagram and the live system:

• Identify each trunk and its protocol (BACnet MS/TP, BACnet IP, LON, proprietary, etc.)
• Count devices per segment and compare to best practice limits
• Look for long daisy chains, bad terminations, or questionable wiring practices in panels
• Ask if there are recurring communication issues and where they occur

If allowed, run simple tests such as:

• Checking round trip times or error counts on MS/TP networks
• Looking for frequent offline and online events in controller histories

Network instability is a perfect justification for both retrofit work and more robust service agreements.

2.4 Inventory controllers and field devices

Walk sample areas and panels to validate what is actually installed.

Capture:

• Controller family and model numbers
• Firmware versions if easily visible
• Mix of legacy and modern controllers on the same trunks
• Third party controllers or field devices that may complicate migration

Note any:

• End of life controllers
• Controllers that are no longer supported
• Areas where the system has obviously been partially upgraded

These details will shape your migration and retrofit strategy.

Step 3. Perform the HVAC System Walkdown

This is where strong HVAC knowledge becomes non negotiable. A good BAS salesperson must be able to look at a piece of equipment and understand what “normal” should look like.

3.1 Central plant

For chillers, boilers, and cooling towers:

• Confirm which system is actually in control: factory panel, BAS, or hybrid
• Note setpoints and if they look reasonable for the application
• Observe whether equipment seems to be short cycling or constantly hunting
• Look for temporary jumpers, manual switches, or handwritten notes on panels that indicate workarounds

Ask the operator:

• Which plant components are most troublesome?
• Do you feel you have good visibility and control from the BAS?
• If you could fix one thing in the plant, what would it be?

Each answer is a potential retrofit line item or PSA service task.

3.2 Air handling units

For each representative AHU, inspect:

• Mixed, return, and supply air sensors: condition, location, and mounting
• Dampers: travel, leakage, and ability to fully open and fully close
• Fans: belt condition, bearing noise, vibration, and VFD display status
• Coils: cleanliness and evidence of reduced heat transfer
• Filters: type, loading, and bypass points

From the BAS, compare:

• Commanded vs actual damper positions
• Discharge air temperature vs setpoint over time
• Static pressure behavior under varying load

Typical findings you should document:

• Economizers stuck open or closed
• AHUs that never go into unoccupied mode
• Constant static pressure that wastes fan energy
• Coils that clearly need cleaning but are ignored

Each of these items is an opportunity to show energy and comfort impact.

3.3 Rooftop units

RTUs are often neglected. For representative units:

• Check whether the economizer linkage actually moves smoothly
• Confirm the sensor hood is intact and clean
• Inspect gas trains where accessible for obvious issues
• Note the presence and condition of any factory or add on controllers

In the BAS:

• Look for excessive compressor cycling
• Check if the RTU ever achieves and maintains setpoint
• Review occupancy and setback schedules

Many RTUs quietly waste energy or underperform. That creates a strong business case for retrofit controls, PSA inspections, and ongoing analytics.

3.4 Terminal units

You rarely have to inspect every VAV or fan coil. Instead, choose:

• Complaint zones
• Critical zones
• A random sampling on each floor

For each sampled unit:

• Verify the damper moves through its full range
• Check airflow readings against expected values
• Test reheat valves for proper control and leakage
• Confirm space sensors are in good locations and not hidden behind furniture

Ask:

• Which zones generate the most hot and cold calls?
• Are there areas that never feel right no matter what you do?

These local issues are powerful sales tools when tied to real occupant complaints.

Step 4. Review BAS Graphics, Trends, and Alarms

Now you stitch together what you saw in the field with how the building behaves over time.

4.1 Graphics

Look at multiple pieces of equipment and floor plans.

Ask yourself:

• Do the graphics actually match what is in the mechanical rooms and ceilings?
• Are operators using the graphics, or do they avoid them and rely on guesswork?
• Are critical points missing from the screens?
• Are there obvious one off overrides that have been left in for months?

Document:

• Inaccurate or outdated graphics
• Systems with incomplete visualization
• Overly complex or cluttered screens

Graphics refreshes and standardization are ideal PSA scope items and can be packaged with retrofit work.

4.2 Trends

Pull up trends for:

• Supply air temperatures
• Zone temperatures in problem areas
• Static pressure
• Valve and damper positions
• Plant temperatures

Look over at least several days, ideally a few weeks.

Identify:

• Systems that constantly hunt around setpoint
• Zones that never quite reach setpoint
• Equipment that seems to run flat out all day and night
• Overrides or hard setpoints that mask deeper problems

Trends let you show the customer real, quantified behavior: hours of simultaneous heating and cooling, wasted nighttime runtime, unstable discharge temperatures, and more.

4.3 Alarms

Review alarm history and active alarms.

Look for:

• The same alarm repeating hundreds of times
• Alarm floods during morning warmup or cool down
• Critical alarms that are disabled
• Points that should have alarms but do not

Ask the operator:

• Which alarms do you pay attention to?
• Which alarms do you ignore now?
• What alarms would you love to have but do not?

Alarm rationalization, cleanup, and design are very attractive PSA deliverables that directly reduce stress for the operations team.

Step 5. Pinpoint Retrofit Opportunities

At this point you have a wealth of observations. Now you sort them into real retrofit opportunities rather than just a laundry list of problems.

Group findings by driver:

• Risk reduction: obsolete controllers, unsupported platforms, single point of failure gateways
• Energy savings: failed economizers, constant speed fans, excessive nighttime runtime, simultaneous heating and cooling
• Comfort and productivity: chronic hot and cold spots, unstable humidity, noisy equipment
• Compliance and reporting: inadequate trending for audits, inability to document setpoints

For each potential retrofit, document:

• The specific equipment and location
• The root cause or technical issue
• The operational impact today
• The probable energy or comfort benefit of fixing it

This mapping allows you to write retrofit scopes that clearly answer the customer’s real pain, not just “replace controller X with controller Y.”

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A Good Moment To Check Your Sales Team’s Technical Depth

If you are honest about everything covered so far, it is clear that doing this well requires more than basic product knowledge. Your salespeople need to understand HVAC systems, BAS architectures, sequences, and field realities at a much deeper level than most are ever given.

If you want to see exactly how strong your team really is in HVAC, BAS, and troubleshooting knowledge, you can use a skills assessment designed specifically for this industry:
https://www.smartbuildingsacademy.com/skills

This gives you a clear picture of where your team is solid and where targeted training could quickly improve their effectiveness on site walks.

Step 6. Identify and Shape PSA Opportunities

While retrofits are often one time projects, planned service agreements create long term relationships and recurring revenue. Use your findings to design PSA offerings that matter.

Look for issues that:

• Recur regularly
• Require monitoring or adjustment over time
• Are easier to prevent than to fix after failure
• Depend on data quality and system housekeeping

Examples:

• Ongoing alarm tuning and rationalization
• Quarterly graphics cleanup and point validation
• Seasonal optimization of plant and AHU sequences
• Periodic field inspections of sensors, actuators, and VFDs
• Annual sequence review to account for building changes

When you present a PSA, do not sell hours. Sell specific outcomes:

• Fewer nuisance alarms
• Reduced comfort complaints
• Documented energy performance
• Predictable equipment behavior

Your site walk findings become direct evidence that those outcomes are needed.

Step 7. Debrief the Customer

A strong debrief bridges the gap between technical findings and executive decisions.

Structure the debrief around three simple buckets:

1. What is working well
2. What is at risk or underperforming
3. What you recommend and why

Use photos and trend screenshots to illustrate your points. Avoid jargon. Connect every technical item to a business impact:

• “This failed economizer is overcooling the space and wasting energy.”
• “These end of life controllers are a reliability risk that could cause long downtime if they fail.”
• “This alarm flood means your team cannot see real problems when they occur.”

Ask for alignment:

• Does this match what you experience day to day?
• Which of these issues concerns you the most?
• What timeline are you working with to address these?

This alignment step makes your future proposal feel like a continuation of the conversation, not a surprise.

Step 8. Build a Proposal That Reflects Reality

When you write the retrofit and PSA proposals, tie each line item directly back to a finding from the walk.

For each major piece of scope, include:

• The specific problem you observed
• The action you propose
• The result the customer should expect

Example:

• Finding: Economizer on AHU 3 is failing to open, causing excessive mechanical cooling and poor indoor air quality.
• Action: Replace actuator and linkage, verify sensor operation, implement proper economizer sequence, trend key points.
• Result: Increased free cooling, better ventilation, and reduced compressor runtime.

Offer options where appropriate:

• Minimum risk reduction
• Optimal performance
• Long term modernization roadmap

For PSAs, present:

• Clear scope broken down by recurring tasks
• Frequency of each task
• Reporting expectations
• How success will be measured

This turns your proposal into a plan instead of just a price.

Step 9. Position Yourself as a Trusted Advisor

The ultimate goal of this process is not just to sell a one time project. It is to become the person or company the customer calls first whenever anything in their building changes.

You do that by:

• Showing that you understand their goals and constraints
• Demonstrating deep technical competence in both HVAC and controls
• Translating technical findings into clear business language
• Creating realistic, phased plans that match budget and risk tolerance

When your site walks are consistent, thorough, and clearly communicated, customers begin to rely on you as their guide for all future BAS and HVAC decisions.

Equip Your Team With the Skills That Make This Work

Everything in this article depends on one critical factor: your people. You can hand someone a checklist, but if they do not understand what they are looking at, they will still miss key issues and opportunities.

If you want your sales and account teams to confidently walk central plants, AHU galleries, rooftops, and BAS front ends and see what others miss, you need to deliberately build their HVAC and controls skill set.

You can take a concrete first step in that direction here:
https://www.smartbuildingsacademy.com/skills

Use that to identify gaps, then build a training plan that upgrades your team from order takers to true trusted advisors.

A site walk done right is not just an inspection. It is a structured, technical investigation that sets up every retrofit and PSA you will ever sell in that building. Put this process in place, develop your team’s skills, and you will see the impact in both your close rates and your project profitability.