Most split system quotes that lose money do not fail on the unit price. They fail on everything around it: a pipe run that was twice as long as expected, a switchboard with no room, a second-storey wall that needed scaffolding, or an old unit nobody mentioned until you turned up. This guide covers how to quote a split system installation so those surprises are priced in, or clearly excluded.
What is the difference between a back-to-back and a standard install?
A back-to-back install puts the indoor and outdoor units on opposite sides of the same wall, with a short, direct pipe run. It is the fastest install and the one most “supply and install” advertised prices are based on.
A standard install is everything else. Many installers define their base install as back-to-back with a set length of pipe included, often around 3 metres, and price anything beyond that as extras. Whatever you choose, write the definition on the quote.
| Factor | Back-to-back | Standard install |
|---|---|---|
| Unit position | Same wall, opposite sides | Different walls, levels or rooms |
| Pipe run | Short and direct | Longer, through roof or subfloor |
| Duct cover | Minimal | Often several metres |
| Condensate drain | Simple | May need a longer run or a pump |
| Labour | Lowest | Varies a lot with access |
What should you check on site before quoting?
Pipe run
Measure the actual route, not the straight-line distance. Note any bends, roof-space sections, subfloor sections and wall penetrations. Check the manufacturer’s maximum pipe length and height difference for the unit, and whether extra refrigerant charge is needed over a certain length.
Electrical supply
Check the switchboard. Many larger split systems need a dedicated circuit, and the manufacturer’s installation instructions will specify the circuit and protection. Check whether there is space for a new circuit breaker or RCBO, the condition of the board, and the cable route to the outdoor unit isolator. If the board needs an upgrade, quote it separately or refer it to a licensed electrician.
Wall type
Core drilling through brick or block takes longer than weatherboard or plasterboard. Note double brick, rendered walls and tiled areas, which need more care.
Access
Single-storey with a clear yard is the base case. Second-storey outdoor units, roof mounting, narrow side paths and units that need wall brackets all add time, equipment and sometimes a second person.
Condensate
Work out where the drain goes. Gravity to a garden or drain point is simple. A long run, or a position where gravity will not work, may need a condensate pump.
Old unit removal
Ask if there is an existing unit. Removal involves recovering the refrigerant, which is a licensed task, plus disposal of the unit. Price it as its own line.
What materials should be on a split system quote?
- Split system indoor and outdoor units (model numbers listed)
- Pair coil (refrigerant pipe) and insulation
- Interconnecting cable
- Condensate drain hose, plus pump if needed
- Outdoor unit mounting: feet, pad or wall bracket
- Plastic duct cover and fittings
- Isolator, circuit protection and cable for the dedicated circuit
- Fixings, sealants and sundries
How do you estimate labour?
Price the base install as a fixed amount based on your average time for a back-to-back, then add extras by the metre or by the item. Your labour rate should come from your own numbers. The charge-out rate calculator in TradieTally builds that from your running costs and billable hours, so your per-hour and per-metre rates are not just guesses.
Example split system installation quote
All prices below are example sell prices only in AUD ex GST, for a single-storey home with the outdoor unit on an adjacent wall. Your prices will differ.
| Item | Qty | Unit price | Line total |
|---|---|---|---|
| 7.1 kW inverter split system (supply) | 1 | $1,650.00 | $1,650.00 |
| Base installation (back-to-back, up to 3 m pipe) | 1 | $600.00 | $600.00 |
| Additional pipe run incl. insulation and cable (metres) | 4 | $65.00 | $260.00 |
| Outdoor unit mounting feet and pad | 1 | $80.00 | $80.00 |
| Additional condensate drain (metres) | 5 | $12.00 | $60.00 |
| Plastic duct cover and fittings (metres) | 4 | $25.00 | $100.00 |
| Dedicated circuit by licensed electrician (up to 15 m cable, RCBO, isolator) | 1 | $480.00 | $480.00 |
| Remove old unit, recover refrigerant and dispose | 1 | $180.00 | $180.00 |
| Subtotal ex GST | $3,410.00 | ||
| GST (10%) | $341.00 | ||
| Total inc GST | $3,751.00 |
Check: $1,650 + $600 + $260 + $80 + $60 + $100 + $480 + $180 = $3,410.00.
Showing each extra as a line helps the customer understand why your quote is more than an advertised “from” price. It also lets you drop a line (like disposal) if the customer handles it themselves, without redoing the whole quote.
What should the quote say the customer is responsible for?
Clear exclusions stop arguments on install day. Common ones to list:
- Patching, painting or making good around wall penetrations beyond a neat finish
- Moving furniture or clearing access to the install position
- Switchboard upgrades if the existing board cannot take a new circuit
- Roof or ceiling access beyond normal manhole entry
- Council, strata or body corporate approvals for outdoor unit positions
State what happens if hidden conditions turn up, such as asbestos or a board that does not meet current standards, and that any extra work will be quoted before it starts.
How much margin should you build in?
Set a target gross margin for the business and check each quote against it before sending. Do not confuse markup and margin: a 25% markup on cost is only a 20% margin. Our guide to markup vs margin for tradies includes worked A/C examples and a conversion table.
Units are easy to compare online, so most of your margin should sit in installation, extras and after-sales service rather than in the hardware.
What licences and compliance should the quote mention?
- Refrigerant handling: anyone handling refrigerant needs an ARC refrigerant handling licence, and the business needs a refrigerant trading authorisation.
- Electrical work: dedicated circuits and switchboard work must be done by a licensed electrician. Some states have restricted licences for A/C disconnect and reconnect work, so check your state’s rules.
- Manufacturer requirements: warranty usually depends on installation to the manufacturer’s instructions, so follow them on pipe lengths, clearances and electrical protection.
List your licence numbers on the quote. It builds trust and separates you from operators who skip them.
How do you add warranty and service upsells?
Every install is a chance to book future work:
- Service and clean: offer an annual or six-monthly service and filter clean as an optional line.
- Extended workmanship warranty: if you offer one, state it clearly.
- Extra units: if the customer mentioned another room, add an optional second unit so they can accept both on the same quote.
How TradieTally helps A/C businesses quote faster
TradieTally includes air conditioning Smart Bundles you can drop into a quote on site: Split back-to-back, Split standard install, Ducted zone add, Split service and clean, and Dedicated circuit for A/C. Add the extra pipe metres, and the quote shows profit and margin before it goes out. See the air conditioning quoting software and A/C estimating software pages, or preview the A/C bundles on our landing page.
Key takeaways
- Define your base install (usually back-to-back with a set pipe length) on every quote.
- Measure the real pipe route and price extra metres separately.
- Check the switchboard and quote a dedicated circuit by a licensed electrician where needed.
- Price access, wall type, condensate and old unit removal as their own lines.
- Check margin, list your ARC licence, and offer a service and clean on every quote.
Quote split systems on site with the extras already built in. Compare TradieTally plans on the pricing page or start your 21-day free trial with no credit card.