Closed system pressure

[ericmark]

My dad bleed his radiators and when I arrived he had zero pressure shown on gauge. However the boiler was still running and some radiators were hot.

Should not the boiler have closed down? Central heating less than 6 months old so should be under guarantee.

Also all lock shield valves were wide open should these have not been partly closed?

Last there was no TRV in hall where the electric thermostat is located. I thought the electric thermostat is only to switch off system in summer and for the variable output boiler to work one must use TRV's?

Please say if wrong but I thought the boiler senses the return water and adjusts flame height to keep return water cool enough to ensure the condensate is formed? Therefore on modern system ALL radiators have TRV's.

I know with old boilers the standard system was to have TRV on all but coolest room and the coolest room used a electric thermostat. But I also was under the impression since the introduction of variable flame boilers the electric thermostat is only to switch off system in summer?

In fact the thermostat could be fitted outside or in non heated part of house.

But before I contact the installers I want to make sure I have it right.

Already I have called them back as they fitted a combi boiler to the existing power shower and I got them to change it for a thermostat valve type. From what I understand that was against the law so I don't have much faith.

 

[Agile]

I am glad that I dont have any customers like you who think they know everything but actually know nothing.

Presumably you would like them to modify it to suit your own ideas on how heating systems should not work?

About the only thing you were right about is that the lockshields should be mostly closed and set to balance each radiator.

Tony

 

[ericmark]

On strength of what you said I went down and turned all lock shield valves off and then re-opened 1.5 turns. Then opening the TRV full I fine adjusted so I could fell difference in temperature between both pipes on each radiator.

Took all day but all radiators seem now to work and no room seems cold.

I checked for air in radiators and found 3 with air in. I will guess due to dad bleeding down stairs without re-pressurising system? I was careful to ensure pressure never went out of green.

Seems now to all work.

However still worried that boiler did not stop working when pressure was at zero! Are you sure it should work at zero pressure? In the past I have come to failed systems and all I had to do was re-fill with loop and I had thought there was a safety device which would auto stop system should it spring a leak?