Greenstar 24i CH OK, No Hot Water

[kron77]

Experts. Seen some similar posts to this on the forum but not with the exact symptoms. Would be appreciative if someone could help out a newbie (first home buyer). So on the weekend I drained the system and moved a radiator then primed up the system and everything fired up nicely on the Greenstar 24i. In the morning, no hot water but great CH.

Nothing obvious on the boiler, no fault lights and when I turn on the HW from the control panel the boiler fires and stays on no problems, but there is no hot water getting to the tank. I have been using the immersion switch for the last couple of days which heats the tank nicely and sorts me out for my shower in the morning but I would like to return it to using the boiler.

Read lots of posts about ensuring that the divert valve is open, and some posts about an air lock but I can't put my finger on it and I would appreciate any advice on how to tackle both of those issues. I don't think it's a problem with the boiler itself, it's less than a year old, well serviced and the boiler man was here last week and gave it the all clear.

 

[Rob]

Feel the CH flow pipe when a tap is run. (pipe on far left)

If this gets hot then your diverter valve motor is faulty. Sometimes resetting power a few times will resolvethe issue

 

[kron77]

hey rob. thanks for the reply. I will give it a try tonight. Do you mean the far left copper pipe? There is a pvc pipe further to the left of the further most left copper pipe. (excuse ignorance here....).

I assume I would also need to ensure that the CH is off before testing this? As when the CH is on, that left most pipe will always be hot, will it not (again, excuse ignorance here...).

 

[kron77]

did a bit more investigations. So I turned off the CH (on the panel) and then turned off the whole unit, left it for 5 mins, came back and then just turned on the HW. Boiler fires for about 10 secs and then the green gas light goes out. There is a noise coming from the boiler, hard to explain, it sort of sounds like running water, but it could also be boiling water. Any ideas?

 

[boabcelt]

Disregard the post about a diverter motor. I think this poster is talking about a combi boiler, whereas it sounds to me like you have a system boiler. If you drained the system, you most likely have an airlock. You could try cracking open the nut on the flow pipework at the cylinder. Have a few old towels handy!