Lost my user manual for the vaillant boiler ecotec plus 824 R1

https://www.vaillant.co.uk/downloads/ecotec-exclusive-user-manual-261415.pdf

you might have a small cold water leak

USE A ELECTRIC METER AND CHECK FOR 120 VOLTS AT CIRCUIT BOARD AT LINE IN AND COMMON , IF YOU DO HAVE 12 0 VOLTS THE LOOK FOR TAPPINGS FOR 24 VOLT OUT PUT MAYBE A BAD TRANSFORMER OR CIRCUIT BOARD

The Symbols should be there whenever the boiler is in use, it confirms the pump is running and the gas valve is open...i.e firing.
the pump overrun may come on after a firing to dissipate excess heat and is what it says, i.e the pump continues to run to keep the hot water moving to prevent the boiler from getting noisey. Sometimes you may see a radiator symbol which means the boiler is doing a 'heating' cycle as against hot water.

wrong category. If you post to correct category you will get a faster response.

We have just had our old system boiler replaced with a vaillant ecotec plus 837 and sounds like a similar working operation to ours. At first I was a little concerned,but I was told by our installer that he was told by vaillant that these very latest boilers size the system on start up for about 10 mins, then take temperature to target flow which you set boiler at. So even by setting target flow temperature very high you still get the initial sizing cycle, which ours was about 30-35c temp. These boilers seem to run biased for efficiency as after a while they modulate the boiler burner down and the radiators run more on the side of warm than really hot like the old type boilers. You also get better efficiency as at lower temperature the boiler condenses better. You will also find you get a more constant temperature in your home rather than over shoots. I was concerned at first, shame there was no info/explanation in user manual as people do need to know that this is normal operation. We are used to ours now, took a month and by the way these boilers can make a creaking noise but was told this normal expansion/ contraction but annoying when sited in bedroom cupboard. Best of luck!

F.22 Dry fire Too little water in the appliance, water pressure sensor defective,
cable to pump or water sensor defective, pump blocked or defective,
pump output too low

this is a COMPUTER section.
I w

http://www.vaillant.co.uk/stepone2/data/downloads/9a/42/00/timeSWITCH_120.pdf