Wikipedia:Reference desk/Archives/Miscellaneous/2017 April 13

= April 13 =

Plummer or Electrician (UK) ?
Hi. I have an immersion heater, and now when I turn it on, all the electrics short out. Assumed it was a fuse, but couldn't find one. As a call-out charge is a not inconsiderable expense, do I first call an electrician: assuming it's a problem with that; or a plummer: assuming it's a problem with the heater? Know this is not a regular ref-desk question, but thanks for any knowledgeable answers. 109.158.132.183 (talk) 15:10, 13 April 2017 (UTC)


 * If it was me, I would call a plumber (note spelling) on the assumption that there is a problem with the immersion heater which will likely mean it needs replacing, which a plumber would do. However, it's not me, it's you, so it's entirely your decision and if you follow what I would do and it involves extra expense, that's not down to me... --Phil Holmes (talk) 15:20, 13 April 2017 (UTC)
 * Unless the OP wants Christopher Plummer to make a house call. ←Baseball Bugs What's up, Doc? carrots→ 18:09, 14 April 2017 (UTC)


 * Immersion heater is our article. I suspect that the unit has developed a leak and will need to be replaced.  Be absolutely sure to unplug it first, then, if you can remove the unit yourself and take it in for replacement, that would be your cheapest option (be sure to have a water-proof vat to place it in, or at least a garbage bag).  Keep the old unit until you install the new unit and verify that it works, in case the problem is elsewhere (like the wiring in the wall).  If you can't do that and don't know anybody who can, I'd go with the plumber first, but talk with him over the phone and ask if an electrician is needed first (you don't actually need a Plummer unless remaking The Sound of Music). StuRat (talk) 15:24, 13 April 2017 (UTC)


 * “all the electrics short out” uh. Depends on how old your home is. Sounds although you have distribution board with modern ELT's etc. There may by a fuze under a little plastic clip on the switch to the tank– check – but that should still be OK if “all the electrics are shorting out” . It will probably be just the element gone, rather than the thermostat as well and thus that is all you need to buy, along with a spanner and some PTFE tape. How to replace an immersion heater element  All can can be bought at same plumber merchant or DIY store. There are two grades of PTFE tape – go for the thinner one, as you will have more chance of the gasket sealing at first try (although one shouldn’t really need it at all).  Remember to wind the tape  round the right way, otherwise it will try to unravel itself as you screw it in. Redring is a good brand to go for in the UK.  Obviously, take precaution such as making sure that the fuze/distribution board is OFF. Don't do in bare feet – ware Wellington’s if you have a pair and have torch handy. You can tell when the tank is empty enough by tapping it.  The sound will indicate the water level. Go easy with the spanner, as the tanks are very thin copper and you don't want to tear them. Estimated time less than 20 minutes but as this is your first time of doing it – say 40. Also consider buying some 'silicon grease' at the store. Not for this job -but the plumbers merchant will be happy to tell you about all the uses it has in the modern home. Oh, and in answer to your question its a plumbers job not a sparky's. --Aspro (talk) 17:09, 13 April 2017 (UTC)


 * You need to replace the immersion heater as Aspro says but don't use PTFE, it won't work. The immersion comes with a fibre washer which under normal circumstances will do the job but I always wipe some water hawk jointing compound around the thread. Also, running the tap won't empty the tank, it will only relieve the pressure so there will still be water coming out when you remove the immersion while the water in the draw off and the top of the tank runs off. Therefore you need to drain down. If there isn't a gate valve, you can bung up the hot water supply in the water storage cistern in the roof or tie up the ball valve (but this will take longer by some fifty gallons), run the hot water tap on the bath (or both taps, if you tied up the ball valve) until the water stops, then attach a hose to the drain off at the bottom of the feed pipe (enters at the bottom) and drain off a further 8 to 10 gallons. With regards to the wiring, it used to be okay to connect to the ring main via a fused switch spur, which must be the case with yours if it is knocking out all the power points, but the practice now is to give it its own dedicated supply. However, you are allowed to connect it as was. The hardest part will be getting the old one out without buckling the cylinder so good luck with that twenty minute window!--Ykraps (talk) 16:33, 14 April 2017 (UTC) (a plumber)


 * Jointing compound is bad for this application ( yet good for the plumber as it will provide more work for him in the future). After time, jointing compound sets hard and makes a future replacement more problematical, since more force will be needed to unscrew the old element.  This  can tear the very thin copper tank. PTFE tape should not be necessary to create a seal but the advantage of using this tape   is that it reduces the metal-to-metal contact and reduces the corrosion bonding between the male and female threads, thus making it easer to remove the element when it needs replacing again. On the same site I gave you is: How to prepare to change an immersion heater element which describes how to drain the system down. After all, plumbers are hardly the sharpest tools in the box (otherwise, they would not be just doing plumbing). So, if they can manage to replace an element so can you and you can do it properly and ovoid having to pay for a whole new tank.. As Ykraps suggested. The heater may be on a spur of a ring main (which is OK). But the previous owner may have done something daft. If it is a spur, it should have a switch (or plug) with fuse of no more than 13 amps. If not, then get it replaced by a sparky if you can't tackle it yourself. Your report that “all the electrics short out” suggest that you have Earth leakage circuit breakers and they are working. If so, it should be the little switch labeled  RCD  on your board/box that trips – as it should in this situation.  The ingress of water through the copper sheath of the element causes a leak of current to earth – hence the name 'earth leakage circuit breaker'.  Let us know if it takes you more than 20 minutes.Aspro (talk) 21:13, 14 April 2017 (UTC)


 * PTFE does not do well at high temperatures and the water inside the cylinder is kept at 60 degrees centigrade. Yes, jointing compound goes off but not so hard it won't crumble under pressure, I think Aspro must be thinking of the white lead putty which was used back in the 70s. Why on earth would plumbers want to make life difficult for themselves? And if Aspro knew what was involved when working out heatloss calculations, drainage invert levels, flow rates and so forth, he wouldn't have made such an ill-informed comment about the intellect of plumbers. At the end of the day, you can trust someone with a CGLI and thirty-five years experience, or you can trust in something read on the internet and reguritated here.--Ykraps (talk) 06:17, 15 April 2017 (UTC)


 * PTFE does just fine at these temperatures PTFE Specifications. Not thinking of white lead putty but modern  Water  Hawk (note: not Hawk White; which you did not point out the difference of). It may crumble (like your argument) but it is the torque required in extracting the old element that is the problem. On an uninsulated tank you can see the copper buckle in the effort to unscrew the element when this stuff has been used. Second:   On large contracts like putting in central heating in a nursing home etc, sure the client will ensure the contractor is competent. Yet  the OP comes across as your average Joe  who needs advice and may not know how to differentiate between the competent tradesman and the less so and wants to avoid unnecessary expense. Also, didn't say that plumbers make things difficult for themselves, there are quite a few however, that can make what should be a  simple fix more expensive for their client. It is a bit like getting your car fixed by a mechanic with just a C&G qualification who says “sorry Gov. Your alternators gone, so that will be £xxx plus labour charges for a new alternator. Have the  job done  by next Tuesday. Come back for it then” compared to someone  with an Automotive Engineering Degree that says “ just the regulator gone- not expensive – just unscrew the cover yourself an pop this new one in.”  Have had  more than 35 years of dealing with con artists & the misguided,  whom insist, their way is the right and only way. To the OP:  if a jobs worth doing, it is worth doing well! Aspro (talk) 14:51, 15 April 2017 (UTC)


 * The OP only wanted to know whose job it was but, in what I can only assume was an attempt at showing off, and without a full understanding of what the job involves or the potential problems, you encouraged them to undertake the task themselves, concluding that it was an easy twenty-minute job. I have lost count of the number of immersions I have replaced but very few have been twenty-minute jobs (I would be surprised if you have replaced more than one). Unlike you, it was never my intention to tell the OP how to do the job, only to point out that it might not be so easy (a drain-down, if required, would take tweny minutes). Contrary to what you believe, most people are not out to rip you off, a loyal customer base is key to a successful business, but if you are having trouble with tradesmen it is probably because of the same ill-informed and supercillious attitude that you have demonstrated here. By the way, I did point out that water hawk ought to be used, and there are at least four different types of PTFE tape, not two.--Ykraps (talk) 08:21, 16 April 2017 (UTC)


 * Thanks for all the comments.109.158.132.183 (talk) 11:30, 16 April 2017 (UTC)


 * You need a good and trustworthy plumber. A plumber, not an electrician.
 * The reason is that this is a "5 minute" job on a bench, but an awkward one in a house can take ages, or can go expensively wrong. Will the heater unscrew?  Most are old and well siezed into place. If you force it, it's very easy to simply rip the top off the immersion heater cylinder. Is there even enough space above to remove the heater? Some just can't be removed that way, without disconnecting the tank pipe connections and moving the whole tank out of the cupboard - or (often easier) dismantling the wooden airing cupboard shelves above it.
 * A bad plumber will look at it, then bill you for a new tank. Which isn't actually that expensive, or that hard to change, but it's a classic job for a cowboy plumber to then rip off the unsuspecting.
 * Also this electrical work will fall under Part P (immersion heaters rarely, and shouldn't, be on plug-in circuits), so it needs to be done by someone who can issue this Part P paperwork. Any electrician, most plumbers.
 * It's a cheap DIY job, but can turn itself into a real nightmare and wrestling match, if the old heater doesn't want to come out. Especially if you're in hard water.
 * While you're in there, improve the timing control for the tank. Electricity is expensive! An electronic "run back" timer can be one easy addition (Press button once, water gets hot, nothing to turn off afterwards). Andy Dingley (talk) 12:18, 18 April 2017 (UTC)

KCTV (Korean Central TV)
÷ Why does the North Korean TV station only broadcast 8 hours a day? Why can't they broadcast 24 hours a day, like a real station? Rmaster1200 (talk) 16:57, 13 April 2017 (UTC)


 * The cost of broadcast and the lack of listeners. When I was young almost all TV stations went off the airaround betime, and came back on at six.  We must have a history of television article. It says RCA broadcast 58 hours a month to NYC in 1937.  Considering the audience, that's paltry.  But there would also have been a lack of set-ownerss. μηδείς (talk) 17:17, 13 April 2017 (UTC)


 * Considering the paltry size of the NK economy and the huge proportion they spend on the military, they have very little left in the budget for anything else. StuRat (talk) 17:29, 13 April 2017 (UTC)


 * In addition to what others have said, if your populace is regimented and citizens should be in bed resting for the next day's work, then why have anything on later than 22:00 or so. † dismas †|(talk) 18:06, 13 April 2017 (UTC)


 * Yeah, The North Koreans should to be treated to modern TV, were one has 57 Channels (And Nothin' On). Subjected to that mush day-in-and-night-out, might cause the middle class to revolt and declare war on the US. Of course, most NK's don't even have radios nor electricity.--Aspro (talk) 19:07, 13 April 2017 (UTC)


 * Yes, and 70 storey highrises with no hot water. μηδείς (talk) 20:52, 13 April 2017 (UTC)
 * The Daily Mail is not a reliable source, in fact it's more like a comic, probably best to ignore anything it has ever said.  The Rambling Man (talk) 02:34, 14 April 2017 (UTC)


 * I am not adding this as a claim to an article, but there are hundreds of foreign journalists The Daily Mail is not blacklisted..  There's nothing wrong with my using the attributed source, and you are free to find another. μηδείς (talk) 03:54, 14 April 2017 (UTC)


 * The Daily Mail has been utterly discredited and is now declared as unreliable by Wikipedia. So yes, it has been blacklisted.  Cheers!  The Rambling Man (talk) 03:56, 14 April 2017 (UTC)
 * If it helps, and I know you like RFCs, please see WP:DAILYMAILRFC. Thanks so much! The Rambling Man (talk) 03:57, 14 April 2017 (UTC)


 * Also, keep in mind the inverse-square law To broadcast twice as far you have to use four times the power.  (I think I have that right, although reflection of the cloud cover may increase the range--a physics wonk can correct me if it's another one of the power laws..)  So, basically the power to broadcast just a little further increases exponentially in general.  That's why some stations advertise their wattage, not their broadcast range. μηδείς (talk) 02:29, 14 April 2017 (UTC)

Cutting back to the chase, where do we have any evidence that the NK national television service does only broadcast for 8 hours a day? Our own article on Korean Central Television is entirely unreferenced in this regard. While the speculation above is all very interesting, we should address the initial question at source, i.e. how do we know that they only broadcast 8 hours per day, and what's a "real station"? e.g. CBeebies only broadcasts from 6am to 7pm (I should know), and that's a "real station". The Rambling Man (talk) 02:38, 14 April 2017 (UTC)


 * We normally assume good faith from questioners excepting obvious trolling, such as the recent question about Anne Frank's supposed'immortality. Otherwise take it to ANI. No one above has done anything inappropriate. μηδείς (talk) 03:48, 14 April 2017 (UTC)


 * That's a non sequitur. I don't understand why we need to take anything to ANI.  I have asked some questions of the OP, you don't need to respond to those unless you can add constructively to the discussion.  The Rambling Man (talk) 03:52, 14 April 2017 (UTC)


 * Of course, Wikipedia's article on Radio propagation will be a good place to start if you wish to know more about how signals propagate and diminish in strength. The Rambling Man (talk) 18:15, 14 April 2017 (UTC)


 * So, I was indeed correct, Radio_propagation, barring other effects, radio waves follow the inverse square law I mentioned yesterday. Thanks. μηδείς (talk) 18:55, 14 April 2017 (UTC)
 * Never in doubt or in dispute. Why you felt the need to take this to two other ref desks and not answer the OPs actual question, I know not.  The Rambling Man (talk) 19:01, 14 April 2017 (UTC)


 * There are some references about transmission times on that equally unreliable source called err, hum what’s its name... Ah, remember now – Wikipedia Media_of_North_Korea ;-) Look at the satellite images of light pollution - NK is black. Their electric generation capacity is  minimal. Mind you, their Programming and schedules appear exiting and  the (few viewers)  also have  extended treats for special events. Korean Central TV output during the party congress. Aspro (talk) 19:36, 14 April 2017 (UTC)


 * I haven't got any sources, but I've watched online streams, and they definitely switch over to a test pattern at the end of a broadcasting day. I seem to recall a few sources out there talking about how "weird" NK's television broadcasts are, but I really would hesitate to use most of those clickbaity sources. It seems probable, however, that those sources would at least quote somebody who is an authority, and whose works can be relied on to improve our article. Anyway, the reason you don't broadcast 24/7 is not so much because of transmission power (though there is absolutely a cost associated with that), but because of personnel. It takes people to run a station overnight. Especially to ensure that nothing controversial gets broadcast. In the US and other western nations, the income from late night advertising, and advances in station automation and standards and practices procedures really mitigate the added labor costs (and regulatory risks) of running the station overnight. I miss those days. There's a scene in the French film The 400 Blows where the protagonist is taking out the trash from his family's apartment, and in the background you can hear an instrumental "La Marseillaise" playing over people's radios. At the time, of course, it gave the the impression that it was quite late at night for a young boy. When I saw the film more recently, I realized the youth of today probably have never heard a station sign off, playing the national anthem, and might not understand the significance of the sign-off. It seems so strange. —/M endaliv /2¢/Δ's/ 19:43, 14 April 2017 (UTC)


 * Yes agree, that the absence of private enterprise in NK means there is no economic driving force for longer viewing hours. Like Mendaliv, I too  miss those days of the national anthem playing (even in the cinema). It denoted the end of the day when one could switch off as everything shut down. Now life is 24/7.Aspro (talk) 21:37, 14 April 2017 (UTC)


 * There are ways of reducing the bill.  BBC Radio 4 broadcasts the BBC World Service overnight while BBC local radio switches to Radio 2.   BBC1 transmits the BBC news channel.   Nighttime BBC2 consists of pre - recorded lectures for Open University students.   When Radio 4 began broadcasting 24 hours it would sign off one day's programmes with the National Anthem and immediately move on to the next day's schedule.   It has an unofficial national anthem, "Sailing By",  which preceded the late night shipping forecast.   The shipping forecast moved elsewhere but "Sailing By" has recently been brought back. 86.176.19.41 (talk) 09:27, 15 April 2017 (UTC)
 * Right, that's the general gist of how they reduce the personnel costs of running overnight: Front-load all the management and quality control work to the day shift and only air prerecorded, heavily vetted material. Ideally running through an automated tape library. Night shift is kept to a skeleton crew of a couple techs, a low-level manager, maybe a censor, and the support and security staff required for them. There are increased equipment costs as well; 24/7 broadcast equipment needs to be more robust, and you need to be able to cut over seamlessly when something fails. That probably requires more day side staff as well, or at least better-trained tech staff generally. It's not rocket science, but at the same time there's no secret to why it's done in the west: There's viewership to support it. —/M endaliv /2¢/Δ's/ 14:23, 15 April 2017 (UTC)
 * The beloved leader approves of continual recorded broadcasts of himself in order to avoid overworking the smiling sympathetic personality of the KCTV announcer. Blooteuth (talk) 14:57, 15 April 2017 (UTC)