What the customer wants from you on site

The customer cannot assess your work. They do not know whether the flow rate is right, whether the strainer was fitted the right way round, or whether the string voltages came out where they should.

So they judge the things they can see. That is not unreasonable of them — it is the only information they have — and it means a technically excellent job can produce an unhappy customer, and a merely competent one can produce a delighted customer, on the strength of things that have nothing to do with the installation.

Six of those things.

They want to know what is about to happen

Most people have never had this done, have no idea what it involves, and will assume the worst if nobody tells them.

Before you start, in whatever form suits you: how many days, which days, what time you will arrive, where you need access, whether the water is going off and for how long, whether the heating is off overnight, where you will park, and where the mess will be.

That last one matters more than it sounds. Most complaints about mess come from customers who were not told to expect it, and a sentence beforehand about where the dust sheets will be prevents nearly all of them.

They want to be told when it changes

Something will be found. The pipework is smaller than expected, a joist is where the cylinder was going, the roof timbers are not what the survey assumed. That is normal and nobody sensible thinks otherwise.

What they mind is deciding without them. A change discovered at ten and mentioned at four, after it has been done and priced, is the beginning of a dispute even when the decision was the right one.

Stop, explain in plain terms, give them the options and what each costs, and let them choose. It takes ten minutes and it is the difference between "they found a problem and dealt with it" and "they did something I didn't agree to".

They want their house left alone

Dust sheets. Boot covers or boots off. Not using the good towel. Not smoking by the back door. Radio at a volume that stays in the room it is in.

This is not about being fussy. For most people it is the first time strangers have worked in their house for a week, and a certain amount of low-level anxiety comes with that. Visible care about the house reads directly as care about the work.

Clear up at the end of each day, not just at the end of the job. A house that is habitable each evening is a completely different experience from a building site that persists for a week.

They want to know when you are running late

Running late is fine. Everybody runs late. Not saying so is what causes the problem, because somebody has taken a day off work and is sitting in.

A text at half past seven saying you will be there at eleven costs nothing and buys an enormous amount of goodwill, while silence until eleven is what gets remembered in the review.

They want their questions answered without being made to feel stupid

They will ask why the radiators feel lukewarm. They will ask whether it is meant to be running all the time. They will ask why there is steam coming off the outdoor unit. These are sensible questions from somebody who has just spent a great deal of money on something they do not understand.

Short, plain answers. The radiators are meant to be lukewarm, because it runs gently all day instead of in bursts. Yes, it should be running most of the time, and turning it off will cost money, not save it. The steam is a defrost cycle and it is normal on a cold morning.

Every one of those questions answered on site is a support call you do not get in November.

They want to be shown how to use it

This is the one most often skipped, usually because the van needs to be somewhere else, and it is the one that generates the most trouble afterwards.

Twenty minutes at the end. Where the controls are and what the two or three settings they will actually touch do. What normal looks like and sounds like. What the hot water schedule is set to. What to do if it stops, and what to check before ringing anybody.

Do it with whoever runs the house day to day, not whoever signed the contract, if those are different people.

A heat pump handed over without this gets operated like a boiler — switched off when they go out, thermostat turned up when the house feels slow — and every one of those habits makes it run worse and cost more. The customer then concludes the technology does not work, and tells people so.

The short version

Turn up when you said. Say so when you cannot. Explain what is happening before it happens and when it changes. Leave the house liveable each evening. Answer the questions properly, however basic they sound. Show them how to run it before you drive away.

None of it is about the installation, and all of it decides what they say about the installation.