Cylinder stat question

[nick69]

Should be an easy one for you guys. (Im dense lol)

Can you get a Cylinder stat with a High and Low limit together or would I have to buy 2 seperate stats.

Its for a solid fuel heating set up. I want the pump for the rads to kick in when the 28mm return reaches 65 but then I want the pump to stop when it reaches 40.

Or would it just be better with one stat set at 60 and let it cycle all the time?

Hope that makes sense!

 

[Boilerman2]

A cylinder stat has a differential of around 15'c so i would use just the one stat and let it cycle i.e on at 60' off at 45'c, i dont think 5'c is worth all the extra hassle

 

[nick69]

As much as 15deg. In that case, one it is then.

If my wife moans (she usually does) about that 5deg in the winter im coming back

 

[D_Hailsham]

A cylinder stat has a differential of around 15'c

The Drayton HTS3 has an 8C differential and Honeywell L641 a 10C differential.

 

[Boilerman2]

Is that right! everyones an Expert

 

[D_Hailsham]

The OP was asking for a differential of 20°C (65°C and 40°C) for the pump start/stop temperatures. Even if he uses a normal cylinder stat set at 60°C, it will switch the pump off at 50°C, which is 10°C higher than he wanted.

In any case, I don't understand why he is using a cylinder stat when he wants to measure the pipe temperature and control the pump.

 

[Boilerman2]

THe reason he is not using a pipe stat is that a pipe stat will only have a 5'c Differential, whereas a Cylinder stat will have a much greater differential, typically 15'c, which is so close to his ideal 25'c he probably wouldn't notice the difference

The OP asked for advice not an internet row

As I said before everybody's an expert
This site has a certain knack of turning every post into a bun fight, which isn't helpfull especially for the OP who must think that we are a bunch of idiots

 

[namsag]

Leave Agile out of this he has not even posted on this topic

 

[D_Hailsham]

THe reason he is not using a pipe stat is that a pipe stat will only have a 5'c Differential, whereas a Cylinder stat will have a much greater differential, typically 15'c, which is so close to his ideal 25'c he probably wouldn't notice the difference

The OP asked for advice not an internet row

Who said anything about starting an argument?

You suggested using a cylinder stat because it has a 15°C differential. I was just pointing out that the differential quoted by the two most popular manufacturers are much less than 15°C.

You now suggest that a pipe stat cannot be used because the differential is only 5°C. If you check the Honeywell and Dryton specs, you will find that the differential for their pipe stats is exactly the sam as for their cylinder stats. So the OP could achieve what he wanted by putting a pipe stat on the return pipe, set to 60°C. The pump would then turn on at 60°C and off at 50°C.

 

[ColJack]

do you have screw in connectors on domestic tanks?

the plumbers where I used to work put in iron elbows that had a "port" on the bend, they screwed a seimens probe stat sleeve into that..

as said before, I'm a sparky and don't know the right terms..

in fact this type of elbow is what they used..

while we used sensors rather than solid state thermostats, you can use this or something similar to do the job..

 

[nick69]

Well I didnt expect this much interest

Ive gone for a Cylinder stat because........well they are cheaper round here.

At the end of the day, if the differential isnt enough then ill buy another for £8 and have a high and a low. Job done.

Oh and guys, lifes too short. chill out.

 

[nick69]

do you have screw in connectors on domestic tanks?

the plumbers where I used to work put in iron elbows that had a "port" on the bend, they screwed a seimens probe stat sleeve into that..

as said before, I'm a sparky and don't know the right terms..

in fact this type of elbow is what they used..

while we used sensors rather than solid state thermostats, you can use this or something similar to do the job..

Thanks for the input fella. I didnt know that existed.