Any ideas about what may be causing this:
Shower type: Bristan Aristan thermostatic bar.
Boiler type: Potterton Promax Combi
Both less than 18 months old.
Ongoing intermittant fault since Christmas (has occurred 4x)
Seems to happen on particularly cold mornings
Thermostatic shower with hot water feed from the boiler runs normally for several minutes and then hot water is lost.
Does not correlate with a drop in water pressure or use of any taps/toilet etc prior to loss of hot water.
If the shower is turned off for a short time and restarted hot water will eventually flow after remaining cold water has been flushed from system.
Indications that this is a boIler problem rather than the shower:
Last time the fault developed the shower was left running to check what is actually happening at the boiler:
Water temp. display had fallen to ~30°C.
No fault indicator shown on display.
Green water flow indicator remained steadily lit.
Yellow ignition indicator cycled on/off every few seconds.
Cycle: light goes on, click is heard, fan starts, light goes off fan stops – this then regularly repeated every few seconds.
When hot water tap in kitchen was turned on to increase the water flow through the boiler – nothing changed and cycle described above continued.
Shower and taps turned off for a short while. Hot tap in kitchen turned on again. This time it went through one failed ignition cycle as described above. The next time the yellow light went on the boiler fired up – initial sound of fan seemed louder than normal.
Shower then functioned normally again.
Problem has only ever happened when drawing hot water via the shower first thing in the morning and takes a few minutes to develop. Small quantity of washing up water will have been drawn prior to using the shower.
Shower type: Bristan Aristan thermostatic bar.
Boiler type: Potterton Promax Combi
Both less than 18 months old.
Ongoing intermittant fault since Christmas (has occurred 4x)
Seems to happen on particularly cold mornings
Thermostatic shower with hot water feed from the boiler runs normally for several minutes and then hot water is lost.
Does not correlate with a drop in water pressure or use of any taps/toilet etc prior to loss of hot water.
If the shower is turned off for a short time and restarted hot water will eventually flow after remaining cold water has been flushed from system.
Indications that this is a boIler problem rather than the shower:
Last time the fault developed the shower was left running to check what is actually happening at the boiler:
Water temp. display had fallen to ~30°C.
No fault indicator shown on display.
Green water flow indicator remained steadily lit.
Yellow ignition indicator cycled on/off every few seconds.
Cycle: light goes on, click is heard, fan starts, light goes off fan stops – this then regularly repeated every few seconds.
When hot water tap in kitchen was turned on to increase the water flow through the boiler – nothing changed and cycle described above continued.
Shower and taps turned off for a short while. Hot tap in kitchen turned on again. This time it went through one failed ignition cycle as described above. The next time the yellow light went on the boiler fired up – initial sound of fan seemed louder than normal.
Shower then functioned normally again.
Problem has only ever happened when drawing hot water via the shower first thing in the morning and takes a few minutes to develop. Small quantity of washing up water will have been drawn prior to using the shower.
