Tellum is a systems integrator
for HVAC contractors.
Business systems, not building controls.
Installs, service contracts, engineer time, parts and invoices sit in different places — and someone rebuilds the picture every week.
We join what you already run into one live picture.
Nothing gets replaced.
- Joblogic
- Sage
- Excel tracker
- Email & WhatsApp
- +156 systems →
- Installs — margin live
- Service — profit per contract
- Cash — month-end builds itself
- Joblogic
- Sage
- Excel tracker
- Email & WhatsApp
- +156 systems →
- Installs — margin live
- Service — profit per contract
- Cash — month-end builds itself
The systems your HVAC business already runs on.
If it's on this list, we've connected it before. If it isn't, we probably still have — .
You're not unusual. This is what running a contractor at this stage looks like.
“Same job, three systems, three different numbers. I spend Friday afternoons working out which one is right.”
That's plumbing, not people. We fix the plumbing.
“The install ran over on labour weeks ago — I found out when the supplier invoices landed.”
An overrun you see after handover isn't managed — it's archived. We show it while the job's still live.
“Month-end takes the FD a week and one spreadsheet nobody else understands.”
Month-end shouldn't be a build project. It should already be there.
Wherever you are with your systems, there's a version of this for you.
You're picking or replacing something.
We help you choose the tools that fit how you actually work — not the ones the salesman liked. Shortlist, trial, decision. Then we set them up properly.
You already have the tools. They don't talk, or they don't do enough.
We customise, connect and extend what you run: integrations, missing reports, automations, the layer on top. Then we keep it working and growing with you.
You have the systems. People use half of them.
We teach your team to run the tools you already pay for — properly, and with the automations that make them worth the money.
Most clients start in the middle. Some start with training and never need the rest.
Tools get you level. The layer gets you ahead.
Choosing, connecting and training put the right tools in place — the same tools your competitor can buy. The Tellum Operating Layer is ours: it sits on top of what you run and bends to how you work. A new metric lands in days, a new workflow in a week or two. Nothing gets replaced.
One live picture. Three things on it.
Every install, cost-to-date against budget — labour, plant and materials — updated as costs land. The MD opens one screen on Monday morning and knows.
Nothing gets replaced. Your ERP stays your ERP. We add the layer on top.
Small first step. No migration. Nobody retrains.
We sign an NDA, then walk you through what we'd connect and how. A demo, not a sales call.
We pick the right technical approach and build a working prototype on your numbers — free, typically within 48 hours. Static data at this stage; the live connection comes with the build. You decide if it's worth going further.
Implementation, customisation, the connecting layer, training — the actual engagement begins. Your systems stay where they are; your team keeps working the way it works.
Before and after
Examples of what we can help you with — real engagements, anonymised, names and some details changed.
6 of 6 engagements
About to buy an ERP they'd have spent a year fighting.
Sage 50, a dozen spreadsheets and a WhatsApp group.
Joblogic for service, Sage kept for the books, one project tracker — live in six weeks.
Project controls lived in an eight-tab workbook next to the ERP.
NetSuite for finance, Excel for procurement, cost-to-complete and forecast.
One portal on top of NetSuite — two order flows, nightly sync, finance stays in NetSuite.
Three sources, three answers to “how did the contracts do?”.
Commusoft for service, Intacct for the books, a five-day month-end in Excel.
One reporting layer: contract profitability, utilisation, callout-to-quote conversion, retentions — nightly.
Nobody could see service recommendations turning into quotes and quotes turning into work.
Money in QuickBooks, pipeline in HubSpot, the PPM schedule in a spreadsheet.
One weekly picture: renewals, recommendation-to-job conversion, utilisation, cash by branch.
Every client's facilities manager asked for the same numbers every Monday.
Safety observations on paper and in emailed photos, workforce reporting in Excel.
Safety, incidents, training and workforce reporting in one place, fed from BuildOps and ADP.
Three acquisitions, three field systems, entities that didn't line up.
Consolidating P&L by branch and division took most of the month.
A consolidation layer on Intacct — common job structure, month-end across all entities in days.
Want to see the layer itself? Same numbers, three front-ends — inside NetSuite, as a modern portal, as Power Apps.
You're probably here the way most of our clients arrive — a colleague passed our name on, or you got a note from me. Either way, good to meet you. If the page doesn't answer your question, ask me directly — I read every reply myself.
Questions we get asked
The stack we see most often in HVAC: Joblogic, SimPRO, BigChange, Commusoft, Sage, Xero — plus Excel, Microsoft 365 and WhatsApp. In total we work with around 160 systems across 21 categories, listed at tellum.works/vendors. If a system has an API, a database or an export, it can be connected.
Pick your first step.
From a free PDF to a working prototype on your own numbers in 48 hours. Pick one — the form below adjusts.