First time Heating Combi boiler

One of the main reasons why it would go off randomly in the night is that you have the night temperature set too high.
DH set it and had it at 18! Far too warm when you are tucked up in bed. Installer changed it to 15 - all quiet.

I would not have night temps at 18 degrees either FranP. That's about my perfect day time temperature. The heating is set to come on at 10 degrees at the moment as it is not needed, it is still fairly mild down here. We don't like the house too hot.

They thought that the problem was something to do with the eco setting. All quiet now.

We have had combi boilers for over 30 years, again no noise from them when working, beyond a very slight rumble when it comes on and settles down. certainly, not the constant cycling the OP describes.

How long is your boiler on each day. We have ours on from 6.00 - 9.00 in the morning and 4.00pm to 10.00pm in the evening, so we sleep in peace at night because the boiler doesnot come on. Obviously everyones decision on the hours their boiler is on will vary, but it is not necessary to have it on 24/7.

Think about when you need heating - and also the temperature you want and insist the fitter programmes the heating system to meet your needs. When we first had CH installed in our last house we had a real tussle with the fitter over when the system went on and off and the temepratures that should be set, because the hours were shorter and the temperature a bit lower than official recommendations.

I think the OP said it's sorted?

We are not using the heating yet MOnica, not needed for a while I hope. It's just on and off as we use the taps.
The problem has been sorted and the boiler no longer starts up every 15 minutes and is now quiet.

We haven't yet set the winter times, just using the manual setting, but they will be around 6-8 in the morning and possibly 4-8 in the evenings. Up until now we have had a gas fire in the living room which was usually only needed in the 4-8 time frame unless it was bitterly cold. The early morning warmth will be nice.

This does not sound completely normal a combi boiler should not be cycling every 15–20 minutes and making enough noise to keep you awake. Most combi boilers are fairly quiet once running with just a gentle hum or pump noise.
In your case it could be short cycling which might mean the thermostat, pressure or boiler settings need adjusting. Sometimes trapped air in the radiators can also cause the boiler to fire more often.t’s great that you’re seeing the installer soon definitely mention the issue and have them listen to the noise while it’s running. They can balance the system, check the pressure and adjust the settings if needed.

For now, if the noise is really affecting your sleep you could try adjusting the thermostat schedule or temperature slightly to reduce how often it kicks in overnight.