vaillant boiler problems

[hwads]

Hi
My parents have a vaillant TURBOmax Pro 24 E. installed about 2001 (ish)

The problem is when we want ch the boiler fires up then burner lights for about 10-15 seconds then goes out, after about 1-2 minutes it lights again then off again and this is repeated.
The flow pipe from the main heat exchanger to the diverter valve is hot but the pipe from the diverter valve to the rads is cooler and cold after about 1 meter or pipe.

Also when i remove the chrome screw from the front of the pump a fine jet of water sprays out constantly, the pump sound noisy and it gets very hot even though the return pipe is cold.

The hot water is fine, Just no heating


Any help greatly appreciated.

Thanks.

Can anyone tell me if the pump is normal when removing screw?

 

[madharris]

could be diverter valve by the sounds does the water work ok if thats dogey aswell perhaps the pump bit of a awkward one need to make sure with the operation of the diverter valve

 

[hwads]

DHW works fine, does hot water only use the pump?

 

[madharris]

no the hot water flows through a secondry heat exchanger the pump will pump water round the boiler and through the secondry heat exchanger thats how the dhw gets hot thats why i suspect the diverter valve because if the boiler fires but no release of the heat the boiler will over heat and shut down untill it cools a bit so to clarify the pump pushes water round ur rads and the boiler only hope that helps a bit

 

[madharris]

but saying all that still cant rule out the pump to be fair

 

[hwads]

i think ill go for the valve, then may change pump later as i think it may be on its way out!

Thanks for your help.

 

[madharris]

its ok mate i have had the same problem a few times and it always seems to be the valve may sound stupid but make sure the flow and return valves are open or there is no blockages if its old could be sludged up

 

[hwads]

Can anyone help regarding the pump?

 

[hwads]

Anyone,,,,