Recent content by UF6

Sorry for replying to my own reply! Has anyone got one of these? http://www.seaward.co.uk/products/VT800D.asp I'm after a new tester and they compare well spec. wise with Fluke and..............they're cheaper!

I've always rated the Steinel Digi Check. Excellent kit. They also do one with LEDs on, we always referred to them as 'Christmas Tree Testers'

One of the worst forms of control is on/off control of flow temperature. This will lead to short-cycling if there is not much lag in the heating system. With a given setpoint, by increasing the prop band, you will introduce some delay into the system. System heats up, switches off and has...

The proportional bandwidth or as more usually called the prop band is the amount of change in measured variable required to drive the device from on to off, open to shut, high to low. (or vice-versa) etc. This is usually a figure in units of the measured variable, say, "the prop band is 2...

I can't imagine it would be the relay. Relay coils seldom go s/c. Is this the one with the plug-in octal relay? If the relay is u/s a standard jobby from RS would do. You should hear the relay energise when the boiler live feed hits. More likely the flue fan. I would suggest you check...

As the rooms heat up, the return temperature will rise and this will switch off the boiler. I'm not sure if the Vaillants look at the return temp independently or the reduction in difference between flow and return temp. With variable temp., you don't need a room sensor/stat to switch off the...

If it's a Riello, I do recall they would occasionally do this. When it happened to me, it was the control box going u/s If this is the case, it's not the fault of the engineer who serviced it!

Presumably he had run out of 'ISOLATE ELSEWHERE' stickers.

No chocolate blocks, not box! Like this

Frost protection and/or pump excercise.