with a humidifer
The heated water pumped through the pipes gets cooled once the exit valve /mixer valve is opened. This results in reduced pressure in the system. So there is chance that air gets sucked into the...
The solar panel pumps are not working,then may be solar panel copper tubes block,may be water not store in feed water tank.
Are you asking about HEATING H/ W or domestic?
you turn around 3 times touch the ground jump up and down 2 times and there you have it.
to smooth it out.