Remeha service A, B or C on the display: what it means, what it costs and which service kit you need

Short answer: service code A, B or C on a Remeha Avanta, Tzerra or Calenta is not a fault but a service reminder. The boiler counts burner hours and starts and uses them to ask for a minor (A), intermediate (B) or major (C) service; it keeps working as normal. The letter only disappears once an engineer has carried out the service and reset the reminder in the service menu. The service kit that goes with it costs € 19.95 to € 47.45, depending on the letter and the appliance. A red light or a code with an E, H or numbers is a fault; you can look those up in the Remeha fault codes.

Reminder or fault: how to tell the difference

Remeha uses the display for three kinds of messages. A service reminder is a flashing letter A, B or C (on the Ace models with the text "Service A" in the menu and in the eTwist app). The appliance works normally, the water gets hot, nothing is broken. A blocking is a temporary stop with a code that disappears by itself once the cause is gone, for example water pressure that is too low. A lockout is a genuine fault: the red light is on, the boiler stays off until you reset it, and the code (E codes on the Ace, numbers on older models) points to the faulty part.

Many people search for "Tzerra fault red light" when only a letter is flashing. So first check whether the light is really red; with a service reminder it is not lit.

What A, B and C mean

The letters stand for three service levels that alternate. Remeha calculates the timing from the number of burner hours, the number of starts and the time the appliance has been powered; the exact intervals are in the installation manual of your model and vary by series. In practice the A comes roughly every one to two years, the B after that, and the C after a number of years as a major service.

The kit contains the gaskets and wear parts that are routinely replaced at that service. Which kit fits depends on your exact model and output: a Tzerra Ace 28c has a different kit from a Tzerra Ace 39c or a Calenta Ace 40c. The type is shown on the rating plate on the underside of the boiler.

What does a service cost?

Instalpunt does not carry out services; have a qualified local installer do the work. Labour rates vary by country and installer; the parts from the A or B kit are charged on top at the shop price. A C service takes longer and needs more parts. Ask the engineer to reset the reminder in the service menu afterwards; if that does not happen, the letter keeps flashing even though the service has been done.

Instalpunt does not install or service boilers; for more information see our installation service. Any certified gas engineer can carry out the service; order the kit in advance so they do not have to come back a second time.

What you may and may not do yourself

What you can do yourself: keep the water pressure at the right level (1.5 to 2 bar when cold), bleed the radiators bleeding, keep an eye on the condensate drain and siphon, and have the service kit ready. If you want to read the reminder yourself: on the Ace models, the number of burner hours and the time remaining until the next service are shown under Menu, Information.

Do not reset it – plan the service

On most Remeha appliances you cannot clear a service reminder as a user; only via the service menu with the installer code. That is deliberate: the reminder is the only prompt that gaskets and electrode are due for replacement. A boiler that runs for years without servicing will eventually develop genuine faults: no flame signal because of a worn ionisation electrode, a blocked condensate trap or a dirty heat exchanger that overheats. Each of those repairs costs more than the service.

Frequently asked questions

What does service code A mean on a Remeha boiler?

Service code A means the boiler is asking for a minor service: checking the combustion, flue, water pressure and expansion vessel, cleaning the siphon and checking the electrode. It is not a fault; the boiler keeps working. Have the service carried out within a few weeks and the reminder reset in the service menu. The matching set A costs € 19.95 to € 40.95, depending on the appliance.

My Remeha is flashing A but I have just had it serviced. How is that possible?

The engineer probably did not reset the reminder in the service menu. Call the installer; resetting can often be done remotely if the boiler is connected via eTwist, otherwise at the next visit.

Can I keep using the boiler with a flashing C?

Yes, the appliance does not block on a service reminder. Do plan the service within a few weeks, though; with a C the wear parts are at the end of their service life.

Which kit do I need for a Tzerra Ace 39c?

The kits for 24/28 kW and 39/40 kW differ because of the larger burner. Search for the exact type from the rating plate in the Remeha spare parts or send us a photo; we will check which kit fits.

Is a service reminder the same as a fault code?

No. A fault code (an E code on the Ace, a number on older models) means the appliance has stopped. The service reminder is a scheduled prompt and the appliance keeps working.

How often does a Remeha boiler need servicing?

Remeha recommends servicing according to the appliance's reminder, in practice every one to two years. Demonstrable periodic servicing by a qualified installer is a condition of the manufacturer's warranty.