Emergency Missed Call Text Back for HVAC and Plumbing: Keyword Triage, Safety Lines, and On-Call Routing

A call at 11 p.m. to an HVAC or plumbing company is rarely a price check. It's water coming through a ceiling, a furnace that quit on the coldest night of the year, or someone who smells gas. If the call goes to voicemail, a plain "sorry we missed you" text doesn't help much: the caller still has to explain everything, and your on-call tech still has to read every message to find the real emergency.

This page is about the triage layer: a missed-call text that asks the caller to reply with one keyword, the safety line each keyword gets back, and the HighLevel (GoHighLevel) workflows that alert on-call and escalate when nobody answers. It builds on pages we've already published. For general plumbing first texts, see missed call text back for plumbers. For what to say on a live call, see the plumbing after-hours answering script and the HVAC after-hours answering script. The safety lines below come from public agencies and utilities, checked October 16, 2026. They are not legal or safety advice for your area: have your owner sign off on every line and match it to your local gas utility's instructions before go-live.

What should an emergency missed call text say?

Name the company, put the gas line first, and give the caller a short list of one-word replies. The gas line goes first because it's the one message where a delay can cost a life, and the caller shouldn't have to reply to get it. Each template below fits in one SMS segment (160 plain-text characters) with a 23-character company name and a short link. Skip emojis and curly apostrophes, since either switches the message to an encoding with only 70 characters per segment (HighLevel: How to Calculate SMS and MMS Costs). You can test your own versions with our free missed call text generator.

First texts (sent automatically after a missed call)

1. After hours, HVAC and plumbing: [Company]: sorry we missed you. Smell gas? Leave now, call 911 from outside. Otherwise reply FLOOD, NOHEAT, NOAC or BOOK.
2. After hours, plumbing only: [Company]: sorry we missed you. Smell gas? Leave now, call 911 outside. Else reply FLOOD, SEWER, NOWATER or BOOK.
3. After hours, HVAC only: [Company]: sorry we missed you. CO alarm or gas smell? Get outside, call 911. Else reply NOHEAT, NOAC or BOOK.
4. Daytime, crew on jobs: [Company] here, sorry we missed you. Reply FLOOD or NOHEAT if it's urgent, or book a visit here: [link]
5. Repeat caller, second missed call: [Company]: we saw you called twice. Reply with your address and what's wrong, and on-call will call you back.
6. One follow-up, only if there's no reply after 10 min: [Company] following up. Reply FLOOD, NOHEAT or BOOK, or just tell us what's wrong in a few words.

Keep the keyword list short. Four or five words is about the most a stressed person will read, and every extra word is another filter you have to test. Use single words without spaces (NOHEAT, not "no heat") in the text, but also listen for the spaced and lowercase versions in your filters, because people won't type exactly what you asked. Template 5 needs a call-count tag or wait step: HighLevel notes that its built-in text-back fires on every missed call, even repeat calls in a short window (HighLevel: Missed Call Text Back).

What should each keyword reply say?

Send one short, approved line, ask for the one thing on-call needs most (usually the address), and say who will call. Don't add DIY repair steps. These work whether a workflow or a person replies; if you use AI, paste them word for word.

7. GAS: If you smell gas, leave now. Don't switch lights on or off or use a phone inside. Call 911 and your gas utility from outside. We're alerting on-call.
8. CO (carbon monoxide alarm): If a CO alarm is going off, get everyone outside now and call 911. Don't go back in until responders say it's safe. We're alerting on-call.
9. FLOOD (burst pipe, active leak): If it's safe, close the main water shutoff. Stay away from outlets or anything electrical near water. What's the address? On-call will call you.
10. SEWER (backup into the home): Sorry, that's rough. Keep kids and pets away and avoid touching the water. What's the address? On-call will call you shortly.
11. NOHEAT: Sorry you're without heat. Please don't heat the home with a gas oven or stove. Is anyone elderly, a baby, or unwell there? Reply with the address.
12. NOHEAT, someone vulnerable or very cold: Thanks, on-call is being alerted now. If anyone is confused, very drowsy, or has slurred speech, call 911 right away.
13. NOAC or NOWATER: Got it. Is anyone at risk from the heat, or is anyone elderly, a baby, or unwell? Reply YES or NO, plus your address.
14. BOOK: Happy to help. Pick a time that works here: [link]. If anything gets worse tonight, reply FLOOD or NOHEAT.

Where do these safety lines come from?

Each one shortens public guidance. Keep the meaning and change the wording only to match your own utility's published steps.

• Gas (script 7): The Pennsylvania Public Utility Commission says to leave the building at once, not to turn lights on or off, not to make calls from a landline or cell phone while inside, and to call 911 and the gas utility from a safe distance (PA PUC: Gas Emergencies). That's why the gas line sits in the very first text: someone who smells gas shouldn't be standing in the kitchen typing a reply.
• Carbon monoxide alarm (script 8): The U.S. Consumer Product Safety Commission says not to try to find the source, to move outside to fresh air immediately, to call 911, to account for everyone, and not to go back in until emergency responders say so (CPSC: Carbon Monoxide Questions and Answers).
• Burst pipe (script 9): Portland Water Bureau's advice is to close the main water shutoff valve, and it notes that apartment residents may need their property manager to do it (Portland.gov). Ready.gov says not to touch electrical equipment if it's wet or you're standing in water (Ready.gov: Floods).
• Sewage (script 10): The CDC says floodwater can contain sewage and advises washing with soap and clean water after contact (CDC: Floodwater safety).
• No heat (scripts 11 and 12): Ready.gov says never to heat a home with a gas stovetop or oven, lists hypothermia signs such as confusion, slurred speech, and drowsiness, and says a body temperature below 95 degrees is an emergency (Ready.gov: Winter Weather).

Our plumbing after-hours answering script explains the leak and sewage sources in more depth, and the HVAC after-hours script covers the gas and carbon monoxide lines for live calls.

Which keywords should page on-call, and which can wait?

Write the routing down before you build anything. A starting table:

Two rules make this safer. First, when a message matches more than one row ("no heat and I smell gas"), the higher row wins, so build the gas and CO routes as their own workflows that can't be skipped by another branch. Second, over-alerting beats missing one: a filter that also catches "no gas smell" wakes someone up for nothing, but a filter that's too tight can miss a real leak. Have on-call read every flagged message, not just the keyword.

How do you build keyword triage in HighLevel?

Use the built-in text-back (or a Call Details workflow) for the first text, then one Customer Replied workflow per route. The steps follow HighLevel's help docs as of October 16, 2026.

1. First text. In the sub-account, go to Settings → Phone System → Voice → Voicemail & Missed Call Text Back, enable Missed Call Text Back, and paste template 1, 2, or 3 (HighLevel: Missed Call Text Back). If you want different texts for daytime and after hours, use a workflow on the Call Details trigger instead and turn the built-in feature off, so callers don't get two texts (Workflow Trigger: Call Details).
2. One workflow per keyword route. Add the Customer Replied trigger, set Reply Channel to SMS, and add a Contains Phrase filter with the keyword and its variants (for gas: "gas," "smell gas," "gas leak"). HighLevel's trigger also offers Exact Match Phrase, tag filters, and an NLP-based Intent Type filter (Workflow Trigger: Customer Replied). Use Contains Phrase for safety routes; intent detection is fine for sorting routine messages, but don't let a model decide whether a gas smell counts.
3. Reply and tag. Add Send SMS with the matching script (7 to 14), then add a tag such as emergency-flood so the morning crew can see what happened.
4. Alert on-call. Add Send Internal Notification, choose SMS, and send it to the on-call user (or Specific Users). Put the customer's message in the alert with the Message Body custom value, {{message.body}}, along with the contact's name and phone (Internal Notification action; inbound SMS notifications). Internal notifications go to users' registered phone numbers, so make sure the on-call phone is set on the user's profile.
5. Escalate if nobody answers. Add a Wait step set to A user to reply, with Timeout on (five minutes is a common starting point). On the timeout branch, alert the backup tech or owner and create a task. HighLevel's own help page uses this exact pattern for response-time escalation (Workflow Action: Wait).
6. Routine replies. For BOOK and NO answers to script 13, send the booking link. If you want a person to follow up, use a Wait with Advance Window set to your business hours, so the follow-up lands in the morning instead of at midnight.

One setting to leave off: workflow settings include a Time Window that pauses communication actions outside the hours you set and resumes them at the next slot (Workflow Settings overview). That's useful for marketing, and dangerous here: the gas reply and the on-call alert would wait until morning. Keep it off on every emergency workflow and test one at 2 a.m. before you trust it.

Our workflow build guide shows the basic text-back workflow click by click, the A2P 10DLC registration guide covers the texting registration you need first, and Voice AI after-hours setup is the next step if you'd rather have calls answered than texted.

Does emergency keyword routing actually work?

Two agencies that build HighLevel systems have published examples, but both are about their own anonymous clients, both are undated, and we can't verify the numbers. Treat them as ideas for what to build, not a forecast.

• HVAC and plumbing company, two vans (reported by Arslan Automates, case study, undated, checked October 16, 2026). The build texts every missed call and checks replies for emergency language such as "no heat," "burst pipe," and "no hot water," sending emergencies to the on-call tech's phone and routine requests to the calendar. The agency reports 89% of missed calls recovered by instant text-back, under 15 seconds from missed call to text, about 14 calls a day routed as emergency or routine, and +26% booked revenue from recovered leads.
• Family-run plumbing company, owner plus four plumbers (reported by GHL Expert, case study, undated, checked October 16, 2026). This one used a short emergency intake form linked from the text instead of keywords, with an on-call rotation: the on-call plumber gets five minutes to accept by reply before the system escalates to the next one. The agency reports 43 after-hours jobs recovered a month, +$27,000 in monthly revenue (it says recovered jobs averaged $630), and Google reviews going from 4.1 stars (38 reviews) to 4.8 (128), which also involved a separate review-request workflow.

Both examples bundle several changes (dispatch, invoicing, review requests, maintenance reminders), so the text-back's share of the result isn't separable. More home-services examples, each with its source, are in our HighLevel case studies database. No income claims: results vary.

How much does emergency text-back cost in HighLevel?

Under a penny per text segment, plus your number and A2P registration. From HighLevel's Phone System Pricing & Billing Guide (modified October 12, 2026), US prices checked October 16, 2026:

These sit on top of a HighLevel plan, which starts at $97/month for Starter (HighLevel pricing); our GoHighLevel pricing guide breaks the plans down. As a rough example, 100 missed calls a month getting one first text, 40 keyword replies coming in, and 40 safety or booking replies going out is about 180 one-segment messages, or about $1.34 in HighLevel's per-segment SMS charges before carrier fees and any internal alerts. Our missed call calculator for HVAC shows what the missed calls themselves may be costing.

What mistakes should you avoid with emergency text-back?

• Hiding the gas line behind a reply. Put it in the first text; don't make someone who smells gas reply GAS to find out they should leave.
• Writing your own safety advice. Use short lines from public guidance and your gas utility, signed off by the owner. No "check the pilot light" or "reset the breaker."
• Turning on the workflow time window. It pauses texts and alerts outside the hours you set.
• Alerting one phone with no backup. Add the "user to reply" timeout so a sleeping tech doesn't mean a missed flood.
• Promising arrival times or prices by text. "On-call will call you" is a promise you can keep; "we'll be there in 30 minutes" may not be.
• Testing only in daytime. Run every keyword, in lowercase and with spaces, after hours on a real phone before go-live.

Related guides: missed call text back for plumbers, plumbing after-hours answering script, HVAC after-hours answering script, AI receptionist for HVAC and plumbing, GoHighLevel call routing with Voice AI backup, missed call text back for roofing.

FAQ

What should an emergency plumber text a missed caller? Name the company, tell anyone who smells gas to leave and call 911 from outside, and ask for a one-word reply: "[Company]: sorry we missed you. Smell gas? Leave now, call 911 from outside. Otherwise reply FLOOD, NOHEAT, NOAC or BOOK." Then send a short safety line and alert on-call for each urgent keyword.

Can HighLevel route texts by keyword? Yes. The Customer Replied workflow trigger has a Contains Phrase filter (and an Exact Match Phrase filter), so you can start a different workflow for "gas," "flood," or "no heat," send the matching reply, and alert on-call with an internal SMS.

What if the on-call tech doesn't answer? Add a Wait step set to "A user to reply" with a timeout, then alert a backup tech or the owner on the timeout branch. One published plumbing example gives the on-call plumber five minutes to accept before it escalates.

Should the text tell people to call 911? For a gas smell or a sounding carbon monoxide alarm, yes: public guidance from the PA PUC and CPSC says to get outside and call 911 (and the gas utility for gas). For leaks and no heat, the text gives a short safety line and a callback instead, and only points to 911 for signs of a medical emergency such as hypothermia.

Can AI handle the replies instead of keywords? HighLevel's Conversation AI can reply to texts, and the Customer Replied trigger has an intent filter, but keep keyword filters as the backstop for gas and carbon monoxide. Give any AI the exact scripts above and forbid repair advice, prices, and arrival promises.

Sources (checked October 16, 2026)