Heat network complaints handling: what Ofgem condition B4 requires

Complaints handling is one of the consumer obligations in Part B of Ofgem’s heat network authorisation conditions, the part where most operators find the bulk of their day-to-day compliance work. It is also one of the conditions that is easy to assume you already meet. Dealing with the occasional complaint as it arrives is not the same as having a compliant complaints process, and the difference matters. This guide explains what condition B4 requires and how operators evidence it. For the full set, see our guide to the heat network authorisation conditions.

What condition B4 requires

Authorisation condition B4 is complaints. In plain terms, you must have a compliant complaints process in place and you must handle complaints in line with Ofgem’s requirements. Two things follow from that. First, the process has to exist as a defined procedure, not just as the way individuals happen to deal with problems. Second, complaints have to be handled to a standard, not simply received. In practice that means a documented procedure with defined timescales, proper recording of each complaint, and clear signposting of escalation to the Energy Ombudsman.

B4 does not sit in isolation. It works alongside the other consumer conditions in Part B, in particular the supplier standards of conduct (B1) and the duty to provide consumers with assistance and advice (B5). A complaint is often the point at which those wider duties are tested, so a strong complaints process supports the rest of your Part B obligations rather than standing apart from them.

Building a compliant complaints procedure

A compliant procedure is a written one. It should set out how a consumer can complain, what will happen once they do, how the complaint will be recorded and investigated, and what the consumer can do if they remain dissatisfied. Writing it down is what makes it possible to follow consistently and to show Ofgem that complaints are handled to a standard rather than case by case.

The procedure should also be accessible. Consumers need to know that a complaints route exists and how to use it, including consumers in vulnerable circumstances who may find some routes harder to use than others. A procedure that is technically in place but effectively hidden does not meet the spirit of the condition.

The complaints process step by step

While the detail will vary by operator, a compliant complaints process generally moves through the same four stages.

1. Complain to the operator. The consumer raises their complaint with the heat network operator first. Operators must make this easy, with clear and accessible ways to complain.
2. The operator acknowledges and investigates. The operator acknowledges the complaint promptly, records it in a complaints log, and investigates it fairly so it can be tracked from receipt to resolution.
3. Final response within 8 weeks, or a deadlock letter. The operator works to resolve the complaint and issue a final response within 8 weeks. If it cannot, it issues a deadlock letter that allows the consumer to escalate sooner.
4. Escalate to the Energy Ombudsman. After 8 weeks, or on a deadlock letter, the consumer can escalate to the Energy Ombudsman. Its decision binds the operator but not the consumer.

Operators must be registered members of the Energy Ombudsman scheme. The Energy Ombudsman has handled heat network disputes since 1 April 2025, and scheme membership became mandatory when Ofgem regulation commenced on 27 January 2026. The Energy Ombudsman is the redress route for heat network complaints: once a consumer has been through your process, they can escalate to it, and its decision binds you as the operator but not the consumer.

Consumers can also get free, independent advice from Citizens Advice, or from Citizens Advice Scotland and Consumer Scotland in Scotland. Your complaints procedure should signpost both the Energy Ombudsman and this advice clearly, so consumers know where to turn.

Logging and evidencing complaints

The single most important piece of evidence for B4 is a complaints log. It is what lets you track each complaint from receipt to resolution, spot patterns, and demonstrate that complaints are handled consistently. Several authorisation conditions are satisfied less by activity and more by having the right records in place and keeping them current, and complaints handling is firmly among them. An operator that handles complaints well but keeps no record will struggle to show it. Operators maintaining these records in a live, append-only register can do so in the AXIS compliance portal, which tracks each complaint through to Energy Ombudsman escalation.

A good log captures the essentials for each complaint: what was raised, the date received, how it was investigated, the outcome, the date resolved, and whether the consumer was signposted to the Energy Ombudsman. Over time it becomes both your evidence of compliance and a source of insight into where the underlying problems are.

How complaints fit the wider consumer obligations

Complaints handling connects to much of the rest of Part B. A complaint about a bill draws in the billing and price transparency obligations; a complaint from a consumer in vulnerable circumstances draws in the Priority Services Register; a complaint about how someone was treated draws in the standards of conduct. Getting complaints right therefore does more than satisfy B4. It gives you an early-warning system for the rest of your heat network compliance. When you register with Ofgem, you confirm that consumer protection arrangements, including complaints handling, are in place.

Like the other conditions, complaints handling is an ongoing obligation. The deadline to be authorised is 26 January 2027, but Ofgem can ask you to demonstrate compliance at any point after that. A documented procedure and a live complaints log are what let you respond quickly when it does.

Frequently asked questions

What is authorisation condition B4?

B4 is the complaints condition in Part B of Ofgem’s heat network authorisation conditions. It requires operators to have a compliant complaints process in place and to handle complaints in line with Ofgem’s requirements. It sits alongside the other consumer obligations in Part B, such as standards of conduct and consumer assistance and advice.

What must a heat network complaints procedure include?

A compliant procedure needs to make it easy for consumers to complain, record and track each complaint, investigate fairly and respond clearly within 8 weeks, and signpost escalation to the Energy Ombudsman if the consumer remains dissatisfied. The procedure should be documented with defined timescales so it can be followed consistently and shown to Ofgem if asked.

Do I need to keep a record of complaints?

Yes. A complaints log is the core piece of evidence for B4. It lets you track each complaint from receipt to resolution and demonstrates that complaints are handled consistently rather than ad hoc. Like several authorisation conditions, B4 is satisfied less by activity alone and more by having the records that show it is being met.

What happens if a consumer is not satisfied with the outcome?

The consumer complains to the operator first. The operator has up to 8 weeks to resolve the complaint or to issue a deadlock letter that allows the consumer to escalate sooner. After 8 weeks, or on a deadlock letter, the consumer can escalate to the Energy Ombudsman, whose decision binds the operator but not the consumer. Operators must be registered members of the Energy Ombudsman scheme. Consumers can also get free independent advice from Citizens Advice, or Citizens Advice Scotland and Consumer Scotland in Scotland.

When does complaints handling need to be in place?

The compliance deadline for the authorisation conditions, including B4, is 26 January 2027. Operating a heat network without authorisation after that date is a criminal offence. Complaints handling is an ongoing obligation, so Ofgem can ask you to demonstrate compliance at any time once you are authorised.