# What an MCS installation should leave behind The paperwork is not a formality. The certificate, the design calculations and the commissioning records are what prove the installation was done to the standard, and they are needed years later. - Kind: Article - Level: Beginner - Category: Paperwork and permissions - Updated: 2026-08-18 - Canonical address: https://ampworth.com/articles/what-you-should-receive > **In short:** You should receive the MCS certificate, the design calculations, a record of how the system was set up, instructions for using and maintaining it, three separate warranties, and copies of the forms the installer sent on your behalf. You need them for grants, export payments, warranty claims and selling the house. When a Microgeneration Certification Scheme (MCS) installation is finished, a set of documents should arrive. They are easy to file and forget. They are also the only evidence of what was designed, what was installed and what it was tested to do. You will need them when you claim a grant or an export tariff, and again if something goes wrong and you call on a warranty. When you sell the house, the buyer's solicitor will ask what that thing on the roof is. ## The MCS certificate Registered by the installer on the MCS database after the work is complete, and issued to you. It carries a unique certificate number, the address, the technology, the capacity and the commissioning date. This is the document grant schemes want. It is also the one an energy supplier wants before paying an export tariff on a solar installation, and the one a conveyancer will ask for. If it has not arrived within a few weeks of commissioning, chase it. Registration is the installer's job, and there is a time limit on doing it. ## The design For a heat pump, this means the room-by-room heat loss calculation. It should list every room with its area, its elements, their U-values and the design temperatures used, and give a total. Alongside it you should have the design flow temperature and the emitter schedule. The schedule shows what is in each room and what it delivers at that temperature. For solar photovoltaic (PV), the output estimate with its five inputs visible: capacity, postcode zone, pitch, orientation and shade factor. A shading assessment where one was needed. A string layout showing which modules are on which input. These are the documents that let anybody check the work later. If a heat pump is not keeping a house warm, the heat loss calculation is where the diagnosis starts, and without it the next engineer is guessing. ## Commissioning records This is the evidence that the system was tested and set up, not merely connected. For a heat pump, the record is the settings as commissioned. They include the flow temperature and weather compensation curve, the system flow rate and temperature difference, and the hot water setting. They should also show how the pasteurisation cycle is arranged and, if anyone worked on the refrigerant circuit, the refrigerant charge. For solar PV, you should receive the inspection and test records required by BS EN 62446-1. They cover string open circuit voltages, short circuit currents, insulation resistance and earth continuity. You should also have the electrical installation certificate for the alternating current (AC) side. The commissioning figures are a baseline. Three years on, when output looks low, comparing against the string test results taken on day one is how a fault gets found. ## Operating instructions These should be written for the householder, not extracted from a manufacturer's service manual. They should explain how to run the system, what the controls do, what to expect it to do, and what is normal. The last of these matters more than it sounds. A heat pump owner who does not know that steam rising from the unit on a cold morning is a defrost cycle will call it a fault. A solar owner who does not know that output falls by four fifths in December will think something has broken. ## Maintenance requirements What needs doing, how often, and by whom. Heat pumps need the outdoor coil kept clear, the system pressure checked, the strainer cleaned and the antifreeze concentration checked where there is one. Unvented cylinders need annual attention by someone qualified for them. Solar systems need very little, and the document should say so plainly without padding it out with invented servicing. Where a manufacturer's warranty is conditional on servicing, this document should state that condition, so that you do not first learn of it when a claim is refused. ## Warranties and guarantees You should receive three separate documents. The first is the manufacturer's product warranty, which covers the equipment. Check its length and what it covers, including whether labour is included, because a compressor covered for parts only is a modest protection. The second is the installer's workmanship warranty, which covers the installation. The third is the insurance-backed guarantee, which is what stands behind the workmanship warranty if the installer ceases trading. MCS contractors are required to hold this, and it is the one people most often assume they have without checking. It is a separate policy document with its own number. ## Notifications made on your behalf The installer should notify building control, usually through a competent person scheme, and give you a compliance certificate. This applies to a heat pump and to the electrical work in a solar installation. The installer should also notify the network operator and give you the reply. A small solar installation comes under G98: the installer connects it first, notifies the operator within 28 days and receives a confirmation. A larger one needs G99 approval, which the installer has to obtain before connection. Copies of both should come with the rest of the pack. ## If it does not arrive Ask, in writing, and be specific about which document is missing. Most gaps are an oversight in the office, and installers usually fill them when you point them out. If asking does not work, the installer's certification body is the next step. It audits the company and can require it to put things right, and a complaint about missing documentation is a straightforward one for them to act on. The certification body is named on the MCS certificate and on the company's entry in the MCS directory. ## Sources - MCS 001-1, Scheme requirements for contractors: https://mcscertified.com/standards-library/ - MIS 3002, Solar photovoltaic systems: https://mcscertified.com/standards-library/ - MIS 3005-D, Heat pump systems: design: https://mcscertified.com/standards-library/ - MCS Customer Commitment, The commitment made to customers: https://mcscertified.com/standards-library/ ## Related - [What MCS certification covers](https://ampworth.com/guides/what-mcs-certification-covers.md): The Microgeneration Certification Scheme (MCS) certifies small renewable energy products and the companies that install them. It is worth understanding what the badge is evidence of before treating it as a guarantee. - [The MCS Customer Commitment](https://ampworth.com/articles/the-mcs-customer-commitment.md): MCS publishes a short document setting out what a certified contractor undertakes to do for its customers. It is worth reading before signing anything, because it describes what you are entitled to expect. - [What a quotation should contain](https://ampworth.com/articles/reading-a-quotation.md): The MCS standards fix the method behind the numbers, so a quotation that follows them has certain things in it. What to look for, and what it usually means when one of them is missing.