The MCS Customer Commitment, in plain terms

Alongside the technical standards, MCS publishes a short document called the Customer Commitment. It is seven pages, it is written for householders, not for engineers, and it is the clearest single statement of what a certified contractor has agreed to do.

What follows is the substance of it, with the reasons the clauses exist.

Before you commit

The contractor should assess the property in person, not quote from a photograph, and should tell you what the assessment found, including anything unfavourable. A survey that discovers a heat loss the customer will not like is still a survey that has to be reported.

The information you are given should let you make a decision. That means the design assumptions, the expected performance, and what the performance figure does and does not depend on. A heat pump quotation without a flow temperature, or a solar quotation without a shade factor, has left out the assumption the whole estimate rests on.

Performance estimates must follow the MCS methods and must not be inflated. This is the clause behind the standardised solar calculation: the point of a fixed method is that nobody can compete on optimism.

The contract

Written, clear about what is included and what is not, clear about the price and about anything that could change it. Deposits should be reasonable and their protection explained.

Cancellation rights should be set out. A contract agreed in your home is generally covered by the cooling-off provisions of consumer contracts legislation, and a contractor that obscures that is not meeting the commitment.

Doing the work

To the MCS installation standards, by people competent to do it, with the site left in a reasonable state and the customer told about anything that changes.

The commitment on changes is the one worth holding installers to. Discovering during installation that the pipework will not carry the flow, or that a roof needs strengthening, is normal. Deciding unilaterally what to do about it, and presenting the customer with the result, is not.

Afterwards

Registration of the installation and issue of the MCS certificate. Handover documentation: how the system works, what it needs, what the warranties cover. A demonstration of the controls, which sounds trivial and is not, since a heat pump operated as though it were a boiler will disappoint everybody.

If something goes wrong

This is the part most worth knowing in advance, because it is the part people look up when they are already unhappy.

The contractor must have a complaints procedure, must tell you what it is, and must handle complaints within reasonable timescales. If the complaint is not resolved, there is an escalation route: to the contractor's consumer code provider, and to its certification body.

Those are two different bodies with two different powers, and using the right one matters.

The consumer code deals with the commercial relationship: the contract, the selling, the deposit, redress. MCS contractors are required to belong to one, and the codes offer dispute resolution, often including arbitration.

The certification body deals with the technical work and with compliance with the standards. It audits the contractor and can require corrective action, and in the last resort can suspend or withdraw certification. A complaint that a heat pump was sized without a room-by-room heat loss calculation belongs here.

Both are named on your paperwork. If they are not, the MCS directory entry for the contractor carries the certification body, and the consumer code should be on the contract.

What it does not do

The Customer Commitment is a set of undertakings enforced through certification, not a statutory right. Withdrawing a company's certification does not repair your installation or refund your money.

Your consumer law rights sit underneath it and are separate: goods and services of satisfactory quality, fit for purpose, as described. Those are enforceable in a way the commitment is not. A card payment over £100 also carries protection under section 75 of the Consumer Credit Act, which is worth remembering when deciding how to pay a deposit.

The commitment is most useful before there is a dispute, as a description of what good looks like. Read against a quotation, it makes the gaps in that quotation quite visible.