Standard Immersion Stats

[jaydebruyne]

After I job I did I'm doubting myself a little and would love some clarification (I have a tendency to overthink things!).

To test a standard open vented immersion stat (only), you put your multimeter set to continuity across the terminals. I've read in a couple of places that you should get continuity when the stat is set to a low temperature and no continuity when set to a high temperature.

Now, I've got a couple of working stats in front of me here and I've tested and opened both of them. When the temperature is set to low the contact lowers and stops continuity between the terminals. The opposite happens when the temp is set to high. (This is the opposite to what I've read elsewhere).

I understand this is only true if the cylinder is cold. If the cylinder water temp has satisfied the stat I'd expect no continuity OR if the stat is faulty and allowing the immersion to overheat the water I'd expect to get continuity regardless of the temperature setting.

When there is continuity the circuit is closed and allows the current to go through to the element, doesn't it?

Am I just being thick or something? (It's not the first time I know )

 

[lame plumber]

if that stat is set to a lower temp than the room temp it wont allow current flow, ie its off when you turn it up and demand heat ie turn on the immersion, youll get continuity as current will be flowing across the stat. you are just using the stat as an on off switch, on and you get continuity off and you wont. So basically, putting it gently in the best possible way, yer being a bit thick , but arent we all at times, its just you probably look sensible unlike our great moderater of short stature

 

[snowhead]

I've read in a couple of places that you should get continuity when the stat is set to a low temperature and no continuity when set to a high temperature.

When the stat is out, you are measuring air temperature.

Stat set to high should have continuity.
Set to low, no continuity providing the low setting is lower than the ambient air temperature that you are in.

 

[jaydebruyne]

if that stat is set to a lower temp than the room temp it wont allow current flow, ie its off when you turn it up and demand heat ie turn on the immersion, youll get continuity as current will be flowing across the stat. you are just using the stat as an on off switch, on and you get continuity off and you wont. So basically, putting it gently in the best possible way, yer being a bit thick , but arent we all at times, its just you probably look sensible unlike our great moderater of short stature

Isn't that what I just said :/ lol

 

[jaydebruyne]

When the stat is out, you are measuring air temperature.

Stat set to high should have continuity.
Set to low, no continuity providing the low setting is lower than the ambient air temperature that you are in.

Exactly. That's what I thought.

 

[lame plumber]

Isn't that what I just said :/ lol

just putting it in another way so thickie would understand

 

[townfanjon]

Jay, i will take a pic and post it later , ( out right now ) on how i test stats, its a bit of a performance , but it works !!
Will try do it tomorrow.

 

[jaydebruyne]

Jay, i will take a pic and post it later , ( out right now ) on how i test stats, its a bit of a performance , but it works !!
Will try do it tomorrow.

Look forward to the performance

 

[townfanjon]

Lol it is , believe me . I must add, this method is patented and anybody using it must send me a tenner every time they test a stat .

 

[drip-dry]

sounds like you are getting in a right stat......

 

[AWheating]

its just a switch, either open (at or above set temp) or closed (below set temp)

 

[BLOD]

Hi Jaydebruyne, don't forget to test for 19 (ish) ohms across imersion element while youre looking at the stat to confirm element is ok.

 

[jaydebruyne]

Hi Jaydebruyne, don't forget to test for 19 (ish) ohms across imersion element while youre looking at the stat to confirm element is ok.

Yeah, was just focusing on the stat on this post but thanks blod

 

[lame plumber]

Hi Jaydebruyne, don't forget to test for 19 (ish) ohms across imersion element while youre looking at the stat to confirm element is ok.

thats a completely new ball park

 

[snoopy8888]

Hi Jaydebruyne, don't forget to test for 19 (ish) ohms across imersion element while youre looking at the stat to confirm element is ok.

it depends on the power of the element, use the formula

(voltage)2/power=resistance

if the element is rated at 3kw

(240)2/3000=19.2 ohms

 

[Dotty]

just putting it in another way so thickie would understand

You mean the way you were taught....

 

[lame plumber]

You mean the way you were taught....

knew he was out there in the ether I see they have just rereleased Croppies training manual, the Ladybird book of plumbing ..................

 

[Dotty]

knew he was out there in the ether I see they have just rereleased Croppies training manual, the Ladybird book of plumbing ..................

I really must send that back to you. Thanks for the loan.

 

[townfanjon]

Jay, Jons stat testing rig, very simple . Steel tube with an immersion heater head in the top of the tube. Put a your multimeter on ohms , put a temp probe into keep an eye on the temp. Slowly heat up the tube ( bottom is open , it aint going to go bang lol )with a hot air gun , keeping an eye on the temp and see when the continuity breaks, when the tube cools the stat will make , and continuity returns. Proves the stat is working or not and more importantly at what temp.

 

[jaydebruyne]

View attachment 21434

Jay, Jons stat testing rig, very simple . Steel tube with an immersion heater head in the top of the tube. Put a your multimeter on ohms , put a temp probe into keep an eye on the temp. Slowly heat up the tube ( bottom is open , it aint going to go bang lol )with a hot air gun , keeping an eye on the temp and see when the continuity breaks, when the tube cools the stat will make , and continuity returns. Proves the stat is working or not and more importantly at what temp.

Wouldn't it be easier to just stick the stat into hot water?? Seems rather time consuming :/