I have consulted the Wiki but what I found there doesn't help me with my problem. So if I may start a new topic please?
As a replacement, installed new in October 2005, my central heating and hot water is provided by a condensing Ideal Icos HE18 boiler. The boiler is wall-mounted in the ground floor kitchen with the FP715 Danfoss controller adjacent. The Grundfos Alpha+ pump and associated valves are in the airing cupboard in the first floor bathroom. The room thermostat is in the hallway centrally between the front and back of the house. The system header tank is in the roof space. The hot water cylinder is also in the airing cupboard and the immersion heater is disabled by removal of its power source fuse.
From time to time since the installation a condition occurs during the time of shut down to restart of the system. The frequency of this condition is spasmodic and can occur as often as several times in a month and also with an interval of more than a year. The main characteristic is the noise that is similar to that of the boiler when fired up but usually much louder coming from the airing cupboard area. The pump is blistering hot and will remains so during the shutdown. The controller's pilot lights are off, the boiler display is showing `c' and the blue LED is flashing on and off. This condition will continue until the system restarts and to the best of my knowledge will not recur at the next daily shutdown. Switching off the power supply to the boiler puts an end to the condition.
This problem has been reported to and investigated by the installer of the boiler and at least two different registered gas engineers and no conclusion has been reached as to the cause let alone the remedy. The latest occurence, last night, after a period of about four months almost passed unnoticed as the noise level, unusually, was very low. Nevertheless all the other symptoms were as reported above.
Now that I have found this forum I am hoping that I might receive some guidance towards identifying and rectifying the cause of this bewildering condition.
As a replacement, installed new in October 2005, my central heating and hot water is provided by a condensing Ideal Icos HE18 boiler. The boiler is wall-mounted in the ground floor kitchen with the FP715 Danfoss controller adjacent. The Grundfos Alpha+ pump and associated valves are in the airing cupboard in the first floor bathroom. The room thermostat is in the hallway centrally between the front and back of the house. The system header tank is in the roof space. The hot water cylinder is also in the airing cupboard and the immersion heater is disabled by removal of its power source fuse.
From time to time since the installation a condition occurs during the time of shut down to restart of the system. The frequency of this condition is spasmodic and can occur as often as several times in a month and also with an interval of more than a year. The main characteristic is the noise that is similar to that of the boiler when fired up but usually much louder coming from the airing cupboard area. The pump is blistering hot and will remains so during the shutdown. The controller's pilot lights are off, the boiler display is showing `c' and the blue LED is flashing on and off. This condition will continue until the system restarts and to the best of my knowledge will not recur at the next daily shutdown. Switching off the power supply to the boiler puts an end to the condition.
This problem has been reported to and investigated by the installer of the boiler and at least two different registered gas engineers and no conclusion has been reached as to the cause let alone the remedy. The latest occurence, last night, after a period of about four months almost passed unnoticed as the noise level, unusually, was very low. Nevertheless all the other symptoms were as reported above.
Now that I have found this forum I am hoping that I might receive some guidance towards identifying and rectifying the cause of this bewildering condition.
