The high / low stat

[Notebook64]

Hi
Apollo myson high low switch on boiler - anyone tell me what temp these operate at / switch.

I take it each side is connected to a stat, but how does the control work - eg it controls the pump running?

 

[Boilerman2]

Low is "about" 55'c High is "about" 80'c

 

[Notebook64]

Low is "about" 55'c High is "about" 80'c

Hi
after some work on my pump and zone valve - on low the pump continually runs all the time. On high it works fine. If I turn the stat on the cylinder down a little then the pump will go on / off with my adjusting this.
could it be that the cylinder stat is too high and so calls the pump to run?

 

[Boilerman2]

I would leave the boiler set on high as this will heat the HW up in the quickest time and then shut down saving energy & cash, on the low setting it takes for ever if at all to heat the hot water