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- Bought it yourself?
You bought it yourself and now you need somebody to fit it
Five kinds of equipment people buy, crossed with the four places they buy them from. What it costs you in warranty, what it changes about the installation, what we will fit, and the one source where the answer is simply no.
Three things that apply to every answer below
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We are not going to be rude about it
Buying your own equipment is a reasonable thing to do and the reason people do it is that the mark-up on equipment in this trade is real. A great many contractors answer this question by quoting a deliberately silly labour price so you go away. We would rather tell you the actual consequences and let you decide.
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Two warranties, and they are not the same thing
The manufacturer’s parts warranty comes with the equipment and belongs to whoever bought it. The labour warranty is a promise from whoever installed it. We stand behind our labour on anything we install, whoever bought it. We will not stand behind the equipment itself, because we cannot.
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Read the manufacturer’s terms before you buy
Manufacturers commonly require registration within a set period, commonly require installation by a licensed contractor, and commonly limit or void cover on equipment bought outside their authorised distribution. Those terms vary by manufacturer and they change. Read the actual warranty document for the actual model rather than the marketplace listing, and if it is not available before purchase, treat that as the answer.
Work out where you stand
Pick what you bought and where it came from. Every answer below is on this page whether you pick anything or not — the picker only narrows it down.
Not a higher price, not a disclaimer, not with conditions. No. Three reasons, and any one of them would be enough. There is no history — a compressor that has been run low on charge, run without oil, or been in a flood looks exactly like one that has not, and there is no test that tells you afterwards. There is no warranty of any kind, so a failure three weeks later is a complete loss and the argument about whose fault it is has no good ending. And we would be signing our name to it — our labour warranty on a used compressor is a promise we have no way to keep. A second-hand thermostat is a different matter and we will happily fit one, because if it does not work you have lost very little. Anything with refrigerant in it, we will decline, and we will tell you plainly rather than price it out of reach.
Send us the model numbers before you buy, not after.
A complete system is the case where a customer-supplied purchase can work well, and also the one where it goes most expensively wrong. The single thing that decides it is whether the outdoor unit, the indoor coil and the air handler or furnace are a matched, rated combination for the model numbers you are buying. Send us the numbers first and we will tell you in ten minutes.
What a complete system needs to have right
- A matched combination. Manufacturers publish rated combinations of outdoor unit, coil and air handler. An unmatched pair will physically run and will not perform as either box says, and its efficiency figure becomes meaningless.
- The right capacity for the house — which comes from a load calculation, not from the size of the unit being removed. Most oversized systems in this valley were sized that way.
- Everything else that is not in the box. Line set, filter drier, whip and disconnect, pad, thermostat, condensate provision, transition and plenum work, and frequently a duct modification because the new coil is not the old coil’s size.
- Delivery and damage. Freight damage found on our install day is your problem with the seller, not ours, and it stops the job. Uncrate and inspect the moment it arrives.
We will quote labour and materials for a supplied system, in writing, with the conditions on the same page. What we will not do is start the job and discover the combination is wrong.
Buying only the outdoor unit is the most common mistake on this page.
A new outdoor unit married to an old indoor coil is usually an unmatched combination, frequently a different refrigerant to what the old coil was built for, and occasionally a straightforward incompatibility. It is the cheapest thing to buy and the most likely to end with the money wasted.
Why the outdoor unit on its own rarely works out
The outdoor unit and the indoor coil are a pair. They are designed and rated together, they have to suit the same refrigerant, and the metering device has to match. Putting a current outdoor unit on a coil from a different era can mean reduced capacity, poor efficiency, a compressor working harder than it should, and a manufacturer who will not entertain a warranty claim because the installation was outside the rated combination.
There are genuine exceptions. If the existing coil is recent, the model numbers are a published match and the line set is in good condition, this is a sensible purchase and we will say so. That is a five-minute check on the model numbers, and it is worth doing before you buy rather than after.
The one situation where it is nearly always right: a stolen or destroyed outdoor unit on a system that is otherwise recent and matched. Even then the line set usually wants replacing.
Check the venting and the gas supply before you check anything else.
A furnace is the one item here where the wrong purchase becomes a safety matter rather than an efficiency one. Condensing and non-condensing furnaces vent completely differently, and a furnace that cannot be vented the way the manufacturer requires does not get installed, whatever it cost.
What decides whether a supplied furnace can go in
- Venting. A high-efficiency condensing furnace vents through plastic pipe to the outside and produces condensate that has to go somewhere. An older-style furnace uses the existing flue. They are not interchangeable, and the route out of the building is frequently the binding constraint.
- Gas supply and meter. The pipe has to be able to deliver the input the appliance is rated for, which is not automatic if the appliance is larger than the one coming out.
- Combustion air. A furnace in a closet needs a defined supply of air. Changing the appliance can change what the closet needs.
- Cabinet size and the coil above it. A furnace that does not physically line up with the existing coil and plenum turns into sheet metal work nobody budgeted for.
- Permitting. Replacing a furnace generally requires a permit and an inspection. We will not fit a gas appliance off the books.
An air handler rather than a furnace is a simpler conversation — it is mainly about matching the coil and the airflow — but the coil match still decides it.
Find out whether it is a pre-charged kit or a proper split system, because they are different jobs.
A great many ductless units sold direct to the public are sold as do-it-yourself kits with a pre-charged line set and a quick-connect fitting. Those exist to be installed without refrigerant certification, and they are a different product from a conventional ductless system that has to be flared, evacuated and charged.
What we will and will not do with a ductless kit
On a conventional ductless system we will do the whole job properly: line set routed where it can be serviced, flares made to a torque figure rather than by feel, a deep vacuum pulled and verified on a micron gauge, refrigerant added by weight for the line-set length, condensate given a fall it can actually use, and the outdoor unit mounted where its vibration does not get into the building. That is the work. It is most of what decides whether the system lasts.
On a pre-charged kit we will fit it and we will tell you the honest limitations: the line-set length is what it is and cannot be shortened without releasing the charge, the quick-connect fitting is a single point of failure you cannot inspect, and a leak there is usually not recoverable. If the run suits the length in the box, these can be fine. If it does not, the kit is the wrong product for the job.
What we will not do is cut a pre-charged line and release refrigerant to make it fit. Venting refrigerant is illegal and handling it requires certification, which is not an inconvenience we work around.
This is the easy one. Buy what you like, but check what wires you have first.
Thermostats and accessories are low-risk, low-cost and the one category where buying your own almost always makes sense. The only thing worth establishing before you order is whether you have a common wire at the thermostat, because a great many modern thermostats need continuous power and a great many older houses do not have that wire run.
What to check before you order
- The common wire. Take the cover off and photograph the terminals and the wires. If there is no C, the options are running a new cable, fitting an adapter at the air handler, or choosing a thermostat that does not need one.
- What the equipment actually is. A single-stage thermostat on a two-stage or variable-speed system will run it, badly, and lose most of what the equipment was bought for. Communicating systems frequently only work with their own manufacturer’s control.
- Heat pump or not. A heat pump needs a reversing-valve output and a different wiring arrangement, and this is the most common ordering mistake we see.
- Filters, humidifier pads and UV lamps are all fine to supply yourself. On filters, buy the size and the rating we tell you rather than the highest number on the shelf — a restrictive filter costs airflow, and on a system already short of it that trade is real.
From a retailer or an online seller
The main thing to establish is whether the seller is an authorised distributor for that manufacturer, because it is frequently what decides whether the parts warranty exists at all. A listing that will not name the manufacturer, or will not show you the warranty document, is telling you something.
Practical points. Get the full model numbers of every component before ordering and send them to us. Confirm the return policy for freight damage and for a wrong purchase, because uncrating happens on install day and by then the job has started. And confirm who registers the warranty and by when — registration deadlines are commonly short and commonly missed.
We will fit properly sourced new equipment from a retailer under our standard conditions: our labour is warranted, the equipment is not, and the conditions are on the quote rather than in a conversation.
Second-hand or from a marketplace
For anything containing refrigerant, we decline. The note at the top of this page explains why, and it is not negotiable at any price.
For everything else the answer is more relaxed than people expect. A second-hand thermostat, a filter housing, a set of registers, a condensate pump, a line-set cover: fit away. The test is simple — if it fails, does it cost you a small amount and an afternoon, or does it cost you the whole system and an argument?
One thing worth saying because it comes up. Equipment removed from a building during a remodel and offered on cheaply is the most tempting version of this, because it genuinely might be nearly new. It might also have sat outside for a winter with its lines open. Nobody can tell which afterwards, including the person selling it.
A contractor’s leftover stock
This one turns on a single question: is it genuinely new, unused, still sealed and with a documented model and serial number? If it is, it is ordinary new equipment and the only complication is the warranty registration, which usually names the purchasing contractor rather than you.
What to ask for: the model and serial numbers before you pay, so we can check the combination and the manufacture date. Equipment that has sat in a yard for three years is new in the sense that it has never run, and old in the sense that the warranty clock may have started at sale to the contractor.
And be careful of the version where a contractor offers to sell you equipment and have somebody else fit it. Ask why they are not fitting it themselves. Sometimes the answer is perfectly reasonable. Sometimes it is that the equipment cannot be installed the way you want it installed.
It came with the house, or from family
Equipment sitting in a garage because a relative had it left over, or found in the roof space of a house somebody just bought, is worth exactly what a documented model and serial number says it is worth. Photograph the plate and send it to us before anybody moves it.
Two things we can tell you from the plate alone: roughly when it was made, and whether it is a combination that makes sense with what is already installed. Both are free and both take minutes. A surprising number of these turn out to be genuinely useful, and a surprising number turn out to be a unit that was removed for a reason.
If it contains refrigerant and it has been sitting with its lines open, treat it as second-hand, with the note at the top of this page. If it is a furnace or an air handler that has been stored dry and indoors, it may well be fine, and the venting and sizing questions are the same as for anything else.
Where this page stops
We will check model numbers and combinations for free, before you buy, and tell you plainly whether a purchase makes sense. We will quote labour and materials for properly sourced new equipment you supply, with the conditions written on the quote rather than mentioned in passing. We will warrant our own labour on anything we install.
We will not warrant equipment we did not supply, will not fit second-hand refrigerant equipment at any price, will not install a gas appliance without the permit it needs, and will not cut a pre-charged line and vent refrigerant to make something fit. If any of that rules out what you were hoping to do, we would rather you knew now than after the crate was open.