If you run a small HVAC or plumbing company, you already have a booking system: a phone, a whiteboard, a shared calendar, and whatever the office manager remembers. That holds up until the first heat wave or cold snap, when two techs end up at the same address and Tuesday's promised quote is still in a notebook on Friday.
This article covers what a 5 to 50 person HVAC shop actually needs, what the established tools do, when to just buy one, and how to build a simpler version by describing it in plain English. I work at Mythex, the AI app builder used in the build section, so weigh that part accordingly.
What a small HVAC shop actually needs
Request intake that saves a callback
A good form saves the callback where you ask what they forgot to say:
- Name, phone, email, and whether they're the homeowner, tenant, or property manager
- Service address with zip code
- Service type: heating, cooling, plumbing, new install, maintenance visit
- Equipment (furnace, heat pump, AC, water heater), rough age and brand
- What's wrong, and whether the system is completely down
- Preferred time windows and access notes (gate code, pets)
- A photo of the model plate
A service area by zip code
Driving 50 minutes for a 30-minute call loses money. Keep a list of zip codes you cover, maybe a second list with a trip fee, and tell anyone outside both before they fill in the whole form.
Emergency vs routine
"No heat" in January and "AC is noisy" in April are different jobs. Write down your emergency rules: no heat in freezing weather, no cooling with an elderly person or infant at home, an active leak. A gas smell is never a booking: the form should tell them to leave and call their gas utility or 911.
Quote, then approval
Installs and larger repairs need a written quote, ideally with options (repair vs replace). The customer approves online, you keep a record of who approved what and when, approved quotes become jobs, and unapproved ones get a follow-up date.
Crew capacity per day
A replacement takes a two-person crew most of a day; a tune-up takes an hour or two. Think in capacity per crew per day, not open calendar slots, so overbooking shows before it happens.
Seasonal peaks
Demand follows the weather. Shops that fill quiet spring and fall weeks with maintenance visits keep crews busy and see fewer surprise breakdowns at peak.
Maintenance-plan reminders
A maintenance agreement (usually a spring and a fall check) only pays off if the visits get booked. You need a list of members and who is due this month.
What the off-the-shelf tools do
Mature field-service management (FSM) products exist for this trade:
- ServiceTitan targets larger and fast-growing contractors: dispatch board, pricebooks, memberships, marketing attribution, accounting integrations. Expect a real onboarding project.
- Housecall Pro and Jobber target small and mid-sized home service businesses: online booking, quotes, scheduling, invoicing, payments, reminders, and a tech mobile app.
Pricing is by plan and often by user; check their pricing pages.
Buy one if you need field payments and financing, accounting sync, truck GPS, a drag-and-drop dispatch board, a parts pricebook, or you have 50+ techs. They've solved problems a home-built app will take a long time to match, and they maintain it for you.
Building makes sense if you want something narrow that matches how your shop works, the big tools feel heavier than you need, or you want the booking page on your own domain with data in a database you control.
Building it step by step in Mythex
Mythex is an AI app builder. You describe the app in chat, it writes the code, runs it in a cloud sandbox with a live preview, attaches a Postgres database and file storage, and publishes it to a public URL or your own domain. There's a starting page for this use case at the HVAC booking system builder.
Step 1: Describe the whole flow
Start with one prompt that covers the full path from request to finished job:
A job board for a family-owned HVAC and plumbing company: customers request a service (heating, cooling, plumbing, new install) with their address and preferred time; office staff see new requests, send a quote the customer approves online, and assign approved jobs to an install crew on a weekly schedule; crews see their jobs for the day and mark them done.
You get a first version with a request form, an office inbox, a quote page the customer opens from a link, a weekly schedule, and a crew day view, backed by database tables. Click through the preview and note what's missing. It's a draft, not a finished product.
Step 2: Add the service area check
Add a service area check. Office staff can manage a list of zip codes we serve and a second list where we add a $45 trip fee. When a customer enters their zip on the request form, check it first: if it's in neither list, show "Sorry, we don't currently serve your area" and don't save the request. If it's in the trip-fee list, show the fee before they submit.
Test it with a zip inside, one in the fee zone, and one outside.
Step 3: Emergency flag and notices
Add a "This is an emergency" checkbox to the request form with the options: no heat, no cooling, active water leak. Emergency requests go to the top of the office list in red with the time they came in. If the customer mentions a gas smell, show a warning telling them to leave the home and call their gas utility or 911, and don't create a booking. When the office confirms a job, send the customer an email and a text that says: "Hi {first name}, your {service type} visit is confirmed for {date}, {time window}. Our tech will call when they're on the way. Reply to this message or call {office phone} to change it."
Email and SMS need a provider (for example Twilio for texts), connected with keys from your own account. Read every test message, because customers will.
Step 4: Maintenance-plan reminder list
Add maintenance plans. A customer can be marked as a plan member with a start date. Each member gets a spring cooling check and a fall heating check. Give the office a "Due this month" list showing members who haven't had their seasonal visit yet, with a button to send them a booking link by email, and let the office filter by zip code so we can group visits by neighborhood.
Step 5: A crew phone view
Make the crew day view work well on a phone: big buttons, the customer's address opens in Maps, a call button for the customer, job notes and the model-plate photo at the top, and "On my way", "Started", and "Done" buttons that update the office view. Add a field for the tech to write what they did and attach photos when they mark a job done.
On Pro you can also build Android (download or Google Play internal testing) and iPhone (TestFlight) apps of the same project. They wrap the web screens rather than being fully native, which is usually fine for a crew checklist.
Step 6: Test it like your busiest week
Walk through it as a customer with a no-heat emergency, as the office quoting and scheduling an install, and as a tech closing a job on a phone. Double-book a crew and see what happens. Then publish to a public link or your own domain, such as book.yourcompany.com.
What the team gets
- A Postgres database with your customers, quotes, and jobs; on Pro, GitHub sync and export of the code.
- File storage for model-plate photos and job photos.
- Your own domain for the booking page.
- Staff sign-in, built by the agent when you ask. There's no ready-made login product, so ask for sign-in and roles (office vs crew) and test them.
- On Business: members-only apps only signed-in colleagues can open, Google Workspace SSO, and required 2FA. Members-only covers a whole app, so it fits the internal side; one setup keeps the request form as a separate public app that sends requests to the internal one. Ask the agent, then test it.
Honest limits
- Payments: Mythex doesn't process payments. To take deposits or card payments, you connect a provider like Stripe with your own account.
- No route optimization or truck GPS. The schedule shows who goes where; it doesn't plan the drive.
- You own the testing. AI-written code can have bugs; test real scenarios before launch and after each change.
- Not a full FSM suite. With 50+ techs, a live dispatch board, and accounting sync on every job, one of the tools above fits better.
For teams
If several people build and change the app, Business (from $50/month) gives you a shared team workspace, roles (Admin, Editor, Viewer), per-member credit limits, members-only apps, Google Workspace SSO with a verified company domain, required 2FA, and publish approvals so nobody changes the live booking page without a second look. Enterprise adds an audit log. A free plan lets you try the first prompt; Pro is $25/month. Details are on the pricing page.
Whichever route you take, write down your intake fields, zip codes, emergency rules, and crew capacity first. That list is most of the work.
Top comments (0)