Hi there

I have a combi bolier which produces water and heating (via water radiators) from mains water supply.

Last year the radiators in my central heating system worked just fine.

My hot water still works fine.

I tried to turn my heating on a week ago, the radiator nearest the boiler (and to a far lesser extent the one next to it) became luke warm in the lower portions. The rest of the radiators remained stone cold.

I decided to bleed the radiators. The first radiator (which had produced some heat) emitted a tiny amount of air and oily water.

When bleeding the second radiator, only clear water came out. However, the nut in the radiator came out completely, and due to the pressure of the water, I could not stop the flow of water out of the radiator until the mains supplies were shut off. This meant that I lost over a bucket of water from the system.

Now zero heat is generated from any of my radiators my central heating system but my hot water remains OK.

When I switch my central heating on, the bolier displays an orange light, which shows that the central heating control switch and radiators are requesting heat (the same orange light shows when I run the hot water tap). The problem is that the light only stays orange for less than 30 seconds before going out. This means that the boiler is not being told to produce heat.

I would really appreciate it if anyone can advise what to do next before I call in the professionals?

Many thanks

Sarah

Combi boilers can be hard to diagnose for a service tech standing in front of the unit. Could be a weak flame sensor signal, does burner stay lit. Could be air in the system, many codes require a low water cut off, of a flow sensor if pump isn't moving water. That could be a bad pump or vapor lock. Did any valves get closed. Water has to flow through the primary loop for domestic water to get hot, but doesn't mean water is flowing through the heating loop.

Sorry, best I can do with what you have said.