Ideal Short Cycling Due to Oversizing or Control Issues

Boiler short cycles (frequently turns on and off) and rooms do not reach temperature

Possible Causes

Boiler output set too high for system, Flow temperature too high, Poor thermostat placement, Low water content system with no buffer

How to Fix / Troubleshooting

Safety first: Adjust only user-accessible controls; do not enter installer menus unless competent.

User checks:

Lower flow temperature: Reduce central heating flow temperature to around 60–65°C to encourage longer run times.
Thermostat location: Ensure the room thermostat is not near a heat source or in direct sunlight.
Radiator valves: Avoid closing too many radiators, which reduces system water volume.

If short cycling continues, an engineer can adjust boiler output settings in the installer menu and review system design.

Repair Difficulty

Easy 2/5