1. starting from a point when all calls for heat are OFF, and the flow and return pipes have cooled:
2. A call for heat comes ON resulting in the flow pipe temperature ramping up to the boiler limit, which turns off the boiler firing.
3. Now what should happen? SFAIUI there are 2 possibilities
- either the flow pipe drops to the lower boiler limit at which point the boiler refires & the heating cycle resumes.
- or the ch control system senses the boiler is OFF; waits a short time, then forces the boiler to refire, giving much more of saw tooth pattern.
Apols if that is not very clear. Alternately can anyone please point to a typical timing diagram? Being able to work out the whys and wherefors of a diagram would probably clear up my queries.