Sime DGT 25 HE - Boiler fault, possibly pump?

[Phillyf]

Hi, I have a boiler that has been here since I moved in around 5 years ago, I believe it's around 6 years old.

Now the problem I have is when I turn the CH on or open the hot water tap, the boiler makes it's usual start up noises and sounds like it is going to work fine then it clicks off with error code 7(safety thermostat error). The Main exchange is hot at the top, not so much at the bottom and after dumping all of the water out of it last night and topping back up it fired up and ran fine until I turned it off for the night.

I thought it might be the pump but it turns freely and is only luke warm and worked after dumping the contents of the system all over the kitchen

Testing the valve for the expansion, air shot out with no water.

Any ideas?

Thanks, Phil

 

[Phillyf]

I just found the air valve on the expansion and on pressing the the valve air fires out with no water, not sure if this will help with the diagnosis.

Thanks, phil

 

[Phillyf]

Another update, I removed the brass screw on the pump and turned on the boiler, I couldn't see anything spin and the water carried on dribbling out, is the pump knackered? It makes a slight ticking noise when it tries to start moving.

Is it safde to say it's the pump? As there is one on ebay cheap at the moment

Thanks, phil

 

[Phillyf]

Sorry to bump again, just can't afford a plumber and it's freezing