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Topic Title: Fault Finding Storage Heaters
Topic Summary: How to test the element and thermostat
Created On: 15 December 2008 03:26 PM
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 15 December 2008 03:26 PM
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deleted_1_kevin432

Posts: 151
Joined: 08 June 2008

Getting quite a few calls lately on faulty storage heaters, most of the time its the thermal fuse.
But got called to this one and i'm stuck on what the fault could be as its not heating up. I've checked the thermal fuse link which is fine, i put the heater on a plug and changed the temp control to max and it didnt heat up like they normally do.

So that leaves me with the element or the thermostat. But i'm not sure how to test the thermostat or element, anyone got any info on what to do or look for.
Pics attached incase you can see something i cant

Pic 1
Pic 2
Pic 3
Pic 4
Pic 5
 15 December 2008 03:37 PM
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Jaymack

Posts: 4587
Joined: 07 April 2004

You're not a plumber are you?
These aren't complicated to test, just a conventional electrical iron with thermostat; but with an overtemperature cutout which may require reset.

Regards

Edited: 15 December 2008 at 03:38 PM by Jaymack
 15 December 2008 03:55 PM
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zeeper

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continuity tester
 15 December 2008 03:56 PM
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JZN

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Use your continuity tester. One probe on each element terminal. If you get a reading then it's OK. If it reads off scale/open circuit, then it's blown and can be replaced.

Some thermal trips can be re-set by pushing a button back in. often requires cover to be removed to do this.

one control knob is mechanical and simply adjust how much the vents are open to govern how quickly the heat is dumped into the room.

The other is a temperature control which is a sort of resistor and governs how much energy is pumped into the thing during warm-up overnight.

Hope this helps a bit.

John
 15 December 2008 04:36 PM
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pnorton

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In picture 1 and 2 you can see the bi-metal strip at the top. On the right-hand end of the strip is a small element which should be in series with the load. Have you got continuity through that small element.

Just in case you didn't know, the idea of this device is to close the flap during the charging period.

Hope this helps

Paul

-------------------------
The body is now decrepit but the mind is still active - just!
 15 December 2008 05:49 PM
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deleted_1_kevin432

Posts: 151
Joined: 08 June 2008

cheers for the help guys
So carrying out continuity test on the element shows whether is broke or not
How about testing the stat, this is the only part now that i'm unsure on how to test?

In picture 1 and 2 you can see the bi-metal strip at the top. On the right-hand end of the strip is a small element which should be in series with the load. Have you got continuity through that small element.

I didnt check continuity on what looks like the damper control
Parts Diagram
I would have thought heat would still come out even if the damper was faulty and in the open position? Is the small element in the housing just to the right of it where the 2 wires are going in. Or is the element in what looks like a terminal connection block?

Edited: 15 December 2008 at 05:54 PM by deleted_1_kevin432
 15 December 2008 07:31 PM
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typiod

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Test lamp on live terminal of element?
 15 December 2008 11:09 PM
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Jaymack

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Originally posted by: typiod
Test lamp on live terminal of element?

Which live terminal? In any case, testing live in this case is a NoNo; since it is unreasonable in all circumstances, read the EWR's. The OP is obviously a novice, we wouldn't want him to learn bad habits; or saying that he heard it on this forum - at the inquiry either down here or up there.

Regards

Edited: 15 December 2008 at 11:10 PM by Jaymack
 15 December 2008 11:50 PM
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dbullard

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No chance it might be the neutral hanging in the breeze in pic 5.

Regards

Daren

p.s i use my megger to check the resitance of the elemnts etc, trade secret a good reading or bad one

-------------------------
..... Dont pee in my pocket and tell me its raining ......


www.quest-electrical-sw.co.uk
 15 December 2008 11:55 PM
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potential

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Originally posted by: Jaymack
Originally posted by: typiod
Test lamp on live terminal of element?

Which live terminal? In any case, testing live in this case is a NoNo; since it is unreasonable in all circumstances, read the EWR's. The OP is obviously a novice, we wouldn't want him to learn bad habits; or saying that he heard it on this forum - at the inquiry either down here or up there.
Regards

I couldn't agree more.

If this was a gas fitter's forum we would not be thanked for helping someone repair an appliance which they don't understand.
Why is it ok here?
And before we get the usual "oh we all need a helping hand sometimes" the internal wiring in a storage heater is quite simple but very easy to make dangerous.
Quite simply, with respect to the OP, I don't think someone should attempt to repair something they don't understand.
It is dangerous and could create a lethal situation.
 16 December 2008 12:31 AM
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FizzleBang

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Originally posted by: Jaymack

Originally posted by: typiod

Test lamp on live terminal of element?


Which live terminal? In any case, testing live in this case is a NoNo; since it is unreasonable in all circumstances, read the EWR's. The OP is obviously a novice, we wouldn't want him to learn bad habits; or saying that he heard it on this forum - at the inquiry either down here or up there.


Unless he does the night shift he might struggle to find the off peak supply switched on anyway!!!

I get called to quite a few of these heaters for letting agents. The input thermostat is the most common component to fail even if the fusible link has gone it is usually caused by a problem with the thermostat. Thermal stress or burned out terminals in that area are common. With the terminals often being completely errode/burned away from the thermostat body due to loose/high resistance connections. But I have known the point of failure to be inside the thermostat body and not be readilly visible.


The model shown in the pictures has a separate damper and thermostat but on the larger models this is a combined unit costing about £50. If the element(s) is in working order and the fusible link is (and apparently it is) in good order then it really leaves the thermostat as being at fault. Only the newer models have the re-setable thermal trip/microswitch. This one doesn't

Unless the heater has recently been charged to full capacity the contacts should be closed in normal room temperature conditions whatever level it is set to. So if the heater is cold you should get a circuit through the stat. If not then it most likely needs replacing.

If the element is open circuit then you will need to do more dismantling. You should use caution in that case as some of these older units do contain asbestos within the casing.

I do have a link to a website listing which ones do and don't. Can't find it at the mo. but Google is your friend!

If you are not entirely confident about what you are doing please bear in mind that after fixing it you will most likely not be there when it is first powered up!! That is unless it's in your own home


Paul

-------------------------
"I learned very early the difference between knowing
the name of something and knowing something". - Richard P. Feynman
 16 December 2008 06:18 AM
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Jaymack

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Originally posted by: FizzleBang
Unless he does the night shift he might struggle to find the off peak supply switched on anyway!!!

He has had enough savvy to put a plug on the cable.
This person (5DW?), is obviously incompetent and more - masquerading as an electrician taking work from bona fide people; and asking advice on basics.
I wonder what he's charging for the time and efforts in faultfinding. Roque Traders you say?

Regards
 16 December 2008 07:19 AM
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normcall

Posts: 8111
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My little grey hairs are multiplying.
I can't believe that a fault on an installation (NSH) in front of you, can't be found.
It's not that complicated or large!

-------------------------
Norman
 16 December 2008 07:28 AM
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AMN

Posts: 644
Joined: 29 June 2007

I would say, particularly looking at the picture, loose connection. I do alot of NSH's and its usually something simple like this. Never work on them live, don't forget you are in someones home, kids, animals about ? there is absolutely no need. Fair enough if you want to check its operation when you have finished and put it back together. It can all be done with a continuity tester.

Regards
AMN
 16 December 2008 08:02 AM
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FizzleBang

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Originally posted by: Jaymack


He has had enough savvy to put a plug on the cable.


Regards


Oh yes

I must read the whole post. I must read the whole post. I must read the whole post..............


Paul

-------------------------
"I learned very early the difference between knowing
the name of something and knowing something". - Richard P. Feynman
 16 December 2008 01:54 PM
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deleted_1_kevin432

Posts: 151
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Thanks for the info guys, some more helpful than others!
Yes i'm a novice with storage heaters hence why i've asked for advice, i'd rather get advice and increase my knowledge on a subject rather than learn the hard way by making something unsafe! This is a forum, so 99% of it is based on questions, answers and advice! None of us have here have never posted a question asking for help - Whats hard for you will be simple for someone else, thats life!

Some of the replys on here are very petty
This person (5DW?), is obviously incompetent and more - masquerading as an electrician taking work from bona fide people; and asking advice on basics. I wonder what he's charging for the time and efforts in faultfinding. Roque Traders you say?

Its answers like this which are normally found on the screwfix forums where the cowboys usually chat, hence why i use this forum as i find i "usually" get more professional replies.

I'm qualified from 2360 upto 2391, latest 17th regs and Part P registered so does that make me a Rogue trader for asking for some friendly advice? Do i need to tell you that in order to get a sensible reply on a subject i have limited knowledge on?

Some people who have replied to this topic wont be Part P registered, so i'm sure wont pay to keep their qualifications upto date, possibly wont have public liability insurance or a decent tester but will still carry out work. Does that make them rogue traders?
Or would you count a rogue trader being someone who knows how to connect sockets/lights but doesnt understand cable sizes/calcs/protection methods etc but carrys out work without testing & certification?
I'm not here to argue/debate so am not going to get into petty arguements -rant over!
For the others- many thanks -you know who you are
 23 October 2010 10:13 AM
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SteveSparks

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Joined: 14 September 2010

Have to agree there. Newly qualified or just first time you've seen something, unless you know what to do with it, you have to ask what to do with it.

There's been some seriously helpful advice here. Being in my first year of working as an electrician, and with winter well and truly on its way, I'm getting an ever increasing number of NSH calls. Most have been thermal cutouts or in one case the clock had died (old, old, old one). I had worked out that simple continuity should show most faults but would like to test that the NSH heats up after repair too. Not that I don't trust my meter, I'd just rather make 100% certain that what I've done is the correct thing. A bit like flicking the light switch to make sure that the lamps aren't blown ;-)
 23 October 2010 03:03 PM
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oldie

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Extra info on storage heaters
Asbestos in storage heaters
 23 October 2010 06:52 PM
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CMD

Posts: 196
Joined: 17 November 2008

Originally posted by: kevin432

Thanks for the info guys, some more helpful than others!

Yes i'm a novice with storage heaters hence why i've asked for advice, i'd rather get advice and increase my knowledge on a subject rather than learn the hard way by making something unsafe! This is a forum, so 99% of it is based on questions, answers and advice! None of us have here have never posted a question asking for help - Whats hard for you will be simple for someone else, thats life!



Some of the replys on here are very petty

This person (5DW?), is obviously incompetent and more - masquerading as an electrician taking work from bona fide people; and asking advice on basics. I wonder what he's charging for the time and efforts in faultfinding. Roque Traders you say?


Its answers like this which are normally found on the screwfix forums where the cowboys usually chat, hence why i use this forum as i find i "usually" get more professional replies.



I'm qualified from 2360 upto 2391, latest 17th regs and Part P registered so does that make me a Rogue trader for asking for some friendly advice? Do i need to tell you that in order to get a sensible reply on a subject i have limited knowledge on?



Some people who have replied to this topic wont be Part P registered, so i'm sure wont pay to keep their qualifications upto date, possibly wont have public liability insurance or a decent tester but will still carry out work. Does that make them rogue traders?

Or would you count a rogue trader being someone who knows how to connect sockets/lights but doesnt understand cable sizes/calcs/protection methods etc but carrys out work without testing & certification?

I'm not here to argue/debate so am not going to get into petty arguements -rant over!

For the others- many thanks -you know who you are
 23 October 2010 10:45 PM
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SteveSparks

Posts: 2
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Originally posted by: oldie

Extra info on storage heaters

Asbestos in storage heaters



Thanks for that. The link didn't seem to work though. Link removed/Storageheaters.htm
IET » Wiring and the regulations » Fault Finding Storage Heaters

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