Steam escaping from indoor boiler

Darwin

Hi, I'd be most grateful as to any suggestions for the following problem:
I have an indoor Grant Euroflame domestic boiler which burns Kerosene. Beside the boiler is a vertical pipe on top of which sits a valve of some description (pressure relief valve ?) Today I noticed steam and black water erupting from the valve so
I immediately switched off the heating. This stopped when the radiators had cooled.
Any suggestions as to what could be wrong ? I had the boiler serviced last October
so it hasn't been neglected

Many thanks for any help.

KoNiT

what temp is the thermostat set at?

Darwin

Hi,
Thermostat is set to 75c - come to think of it I did turn up the thermostat a little before I noticed this happening. The max setting is 85 though.

pipers

Describe the valve, does it have a red handle? Or is it brass? A pic would be useful.

Check that the thermostat is working correctly, also check that the pump is working.

If the system is sealed, check that the cold feed valve is closed.

KoNiT

i'd consider 75 a bit high, 62-68 is more like it depending on the weather

pipers is spot on with the pump as a culprit (hopefullly!)
put your hand on the pump & see it its working (vibration) if its not then you'll have to pull it out & see does it work.

Darwin

Hi again,
Thanks very much for the prompt replies and suggestions, especially on Easter Sunday I ran the heating this morning on the lowest setting and all was well - both the thermostat and pump appear to be working. The cold feed valve is also closed. It would appear the boiler doesn't like temps at 75 or more! Here's a picture of the valve for what it's worth.

pipers

The red handled valve is a pressure relief valve, otherwise known as a safety valve. It is designed to blow at 3 bar, it prevents excess pressure form building up in the heating system. I would recommend that you investigate the cause of the excess pressure.

The optimum temperature is 82c.

Darwin

Thanks for that Pipers, I will have it checked out.