roomstats/cylinder stats

[diditrain]

On a standard combi boiler with a roomstat fitted when the temperature falls below the set temperature the boiler fires up and brings the room back up to temperature. Correct

On a system boiler say a y plan for example the call for heating or hot water comes from the programmer when selected by the user. Correct

If the programmer is on but you are not calling for heating or hot water do the stats spring into action if the room temperature falls below the temperature on the stat or the temperature of the water in the cylinder drops below the stat temperature setting?

Just a little bit unsure so if anyone would like to comment then feel free

Thank`s

 

[Guest123]

Hi.

If the timeclock isn't in one of it's "on" settings either timed or constant, there is no power to either stat so no matter what the temperature it wont start to warm until the timeclock switches to an "on" setting.

 

[electric-ian]

Hi,
Yeah, its as Lenny said but if it's running without demand from prog then there maybe a frost stat either in the boiler, the prog or a stand alone one.

Is it happening when it's really cold?

Or if you're trying to achieve a minimun temperature when the prog is off you could wire in another room stat to bypass the prog..

 

[diditrain]

Thank`s for the replies.
It was just a general enquiry to get a better understanding of how everything works and when it should etc.
Just fitted a one with off, on, once and timed settings.

So it would need to be in the once or timed mode and then the stats set to the desired temperatures then?

 

[Sintra]

The stats are basically just connected in series with the time contol system.
So time clock must be on and stat calling for heat to send signal to boiler.

 

[electric-ian]

Basically, when the prog goes on, it switches live to the stat. If the stat calls for heat it tells the valve to open then when the valve is open it switches live to the pump & boiler.
Heating works that way, and also hot water in an S-plan system
Hot water in a Y-plan is slightly different, using a two-way circuit to tell the mid position valve where to sit ie. middle for both or just heating / water.

Start with cylinder at about 60C and room ablout 20C and adjust when the place is up to temp.

 

[diditrain]

Thank`s for the replies. Got it clear in my head now. Read the instructional manual and it states that the on setting means continuously on