Thermostat electrics

Postby paul100 » Mon Jul 21, 2008 3:16 pm

This query might be related to the 'Central Heating' forum, so I've posted the topic there too.

A few weeks ago when I turned on my hot water, the CH came on also. When I turned the hot water off, the CH remained on. A heating engineer called out, who said the electrics in the thermostat were old, in a poor state of repair and needed replacing. He advised that an electrician would need to do the work. However, when the electrician called out he said that it's a heating engineer's job. I'm stuck. I would have thought that replacing wires in a thermostat would be an electrician's responsibility. Any advice would be much appreciated.

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Postby sparx » Mon Jul 21, 2008 4:25 pm

Hi Paul, you do seem to have some poor tradesmen in yout area!
diff. between plumber & heating eng. we are always being told is heating engineer (sic) can do controls as well as pipework!
Any proper leckie worthy of the title (ie not a 5 day wonder) should be able to change a stat. -room or cylinder ( you don't say which) but personally it seems more likely to be a stuck motorised valve, which if it needs changing is a plumbing job due to draining system,
regards SPARX
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Postby ericmark » Mon Jul 21, 2008 10:28 pm

You do seem to be unlucky in your chose of tradesmen. Central heating does seem to cause some problems I think because there are so many systems the Honeywell C, S, W and Y plans being the most popular.
If the heating is of a combo type then many of the suppliers will only supply corgi registered personal with parts and sometimes only authorised agents. And even after the electrician finds the fault he can’t always get even electrical parts hence passing to heating engineer often needing to be authorised by manufactures to work on that make of boiler if this is the case try manufactures web site.
Most electricians will repair any electrical items outside the boiler itself. Although there are some semi-computerised systems which sense the outside temperature as well as inside so they will not run the central heating when it is getting warm outside. These systems are beyond the normal domestic electricians normal work. Having sensors which need the manufactures data sheets to test and the normal electrician is unlikely to have the information to hand and again may need some manufactures authorised agent to have access to setting information.
First glance at your problem I thought what sort of electrician would walk off without fixing but looking at what you say more careful most non combi systems would be turned on and off with the programmer (Posh word for timer) so to turn on and off with thermostat seems odd. I know my central heating has a programmable thermostat but if it goes wrong I would just change it not repair it.
So what is special about your system? I can’t understand the heating engineer turning down the work normally they are very keen to tell us how they do whole job including electrics.
Out of interest can you tell us more like make and type of boiler and thermostat and if there is any programmer or motorised valves etc.
I will watch with interest.

Postby htg engineer » Tue Jul 22, 2008 10:55 am

I know many electricians that wont touch heating controls. I get jobs where electricians have been and I have to go and renew the programmer or thermostat.

Don't know why.

heating engineer (sic) ??? where's the error ?

htg engineer
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Postby ericmark » Tue Jul 22, 2008 5:04 pm

Hi htg,
I have also seen many tradesmen would pick and choose their jobs and will not attempt anything they are not totally familiar with.
I spent most of my time as an expat and we got comment it’s electrical and you’re an electrician so fix it.
In the UK I can understand how people specialise with washing machines, fridges, and central heating.
What I can’t understand is why anyone who does not want to work on central heating would ever turn up to fix it? I would have thought that should have been all sorted out on the phone? Which is why I wonder if there is something special about it? Yet the electrician was second tradesman and one wonders why a “Heating Engineer” would say it required an electrician if it was something specialised and not recommend the specialist? Also why the “Heating Engineer” did not repair it him self? I would have thought they would have all been Part P registered something seems strange!
Also calling yourself an engineer I will assume you have a degree like myself and it is sometimes hard to realise what limited training some so called tradesmen have I saw on a trade forum how a guy with a C&G 2377 considered himself an electrician those in the trade know it is only for PAT testing but out of the trade a qualification in “In service inspection and testing of electrical equipment” sounds very grand but at best a 12 hour course. I am sure the same applies to every other trade but Joe public would not realise how basic the training was.
I wait with interest to find what type of central heating was fitted. And hopefully why Paul is having the problem. After all 4 wires is maximum you would expect in a thermostat normal being 2 not counting earth. But as I said people like you and me seeing for example blue and white or any of the other standard compensating cable colours would immediately realise what we were looking at but there must be many would have never seen remote sensors and 5 – 20 ma etc. One can understand how it could cause a problem.
All best Eric

Postby paul100 » Wed Jul 23, 2008 6:56 am

Thanks for the replies. Very insightful.

I'm actually renting out the property at the moment while I'm away working elsewhere so all of the info is being received second hand from the letting agent. I'm waiting on a full report from the agent detailing the full situation.

I've queried why an electrician was sent out when it would seem obvious to me that they would be reluctant to do the job. The information on their call-out invoice is very limited. It could be the case the letting agent did not explain the problem fully or the electrician was happy to call out and pocket the call-out charge. I'm also surprised the heating engineer turned down the job.

As soon as I get more info I'll let you know.


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Postby htg engineer » Wed Jul 23, 2008 11:17 am

I'm very surprised a Heating Engineer turned the job down too, unless he is a Gas Fitter, contrary to belief you do not need a degree to be an engineer. not surprised the electrician couldn't do the job. You have plumbers, gas fitters or Heating Engineers.

This is typical going off the Plumbers, Gas Fitters and Heating Engineers I know :-

Plumbers - obviously unable to touch gas, or electrics. Many wont work on heating systems, just hot and cold water and drainage.

Gas Fitter - repairs and installs gas pipes, repairs appliances (normally limited knowledge) but don't normally do plumbing eg radiators, 3 port valves and heating installations.

Heating Engineers can do any plumbing work, and gas work, repair boilers, electrical fault finding, heating installations etc etc etc etc.

I know people with degree's - haven't a clue how they got them. If I had a dog I wouldn't trust them to look after it. Before I get people's backs up - I'm not refering to everyone with a degree. But just because you have a piece of paper - it doesn't always mean that much.

htg engineer
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Postby ericmark » Thu Jul 24, 2008 6:21 am

htg engineer,
To me an engineer must hold a qualification above level 3 and as such be eligible to join organisations like the IET whether this is pure academic or one of the position generated awards like CEng / IEng / EngTech is immaterial. I agree does not need to be a degree a HNC or HND would also qualify but it needs to be a higher education award rather than the level 3 awards given in most further education establishments. And yes as with any academic qualification it does not mean you are good at hands on work this is a tradesman’s job but I am sorry to say in today’s world it is the bits of paper that matter from the corgi registration to Part P and 17th Edition it’s all bits of paper there are some trades and professions which have today escaped the continual updating but these are getting less and less seems doctors are soon going to have to update their skills. One of the problems is the limited scope of degree’s and the like where people have had a blinkered education my degree in electrical and electronic engineering concentrated on the electronic side and taught me very little electrical work but as with all engineering degrees it taught me the maths to be able to work it out. But if you think a CEng / IEng / EngTech etc does not mean much your living in cloud cuckoo land. Remember these are gained after the degree and show some knowledge in the field the degree is only a stepping stone to get these qualifications.
I will agree in America the guy who shovels coal on their old steam trains was called an engineer but this is America where people graduate when they leave school in the UK we look at the name different and where people have proved their worth degrees and sometimes awarded to recognise the fact as with Fred Dibnah and in history many of the greats were self taught but they all were given some bit of paper as you put it the recognise their skills. But of course things do change the only true Plumbers now are organ builders as the only trade still allowed to work with lead but we now expect a Plumber to work with copper and plastic and to try to rename would only confuse people especially when the name pipe fitter is already used for those working with ferrous pipes of large diameters such as found in power stations. But to me you are a heating and ventilation fitter if under level 4 and a heating and ventilation engineer if level 4 and above. The guy who redirected to job to an electrician to me was a heating and ventilation fitter where as even if you have not passed the exams I am sure you could apply for the equivalent in your trade of CEng / IEng / EngTech so you would be a heating and ventilation engineer the fact you haven’t paid your dues to get the letters is immaterial to me you could get them if you applied I am sure. Don’t under rate yourself from your posts on here your are very clever and deserve the title. The only difference in level 3 and levels above that really is the maths being able to work with imaginary numbers and calculus the latter I could no longer do anyway and never needed to use. I may still use Karnaugh maps from time to time but programs like electronics workbench will work them out anyway. I would expect the better systems you work on would have PLC’s and SCADA control which is really level 4 work and to work on PLC’s and SCADA means you have same or better skills to those who took the academic route. But the heating and ventilation guys I have met could not even work out what size of expansion vessel was required and used trial and error method until they had a big enough vessel so we didn’t have to re-fill the system every time it cooled down. Simple to you I am sure but we had three come to sort it out and non of them could do the maths. Neither could I but it was not my job sure there is a simple formula of length and diameter of pipe etc. So as one engineer to another don’t under rate yourself.
All best Eric

Postby TOPSPARK » Sat Jul 26, 2008 7:49 pm

Hi paul100 Topspark here. As a spark i am asked about a lot of different topics and called out for a lot of different reasons for letting agents and alike.Your best bet would be to find an electrician who knows about central heating systems and their plans wether it be c,y,w, or the most common s plan all of which can be found on the honeywell website. if the electrician has this knowledge and skill like myself he should solve the problem easily .
all the best
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