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Thread ID: 115189	2011-01-06 08:19:00	Water heating elements... Reality check?	The Error Guy (14052)	PC World Chat

Post ID	Timestamp	Content	User
1167694	2011-01-06 08:19:00	Ok, time for onother one of my useless threads that probably no one cares about :p I just got hold of a hot water cylinder thermostat so I now need a heating element. Checked trade me and didn't see many elements, I wasn't very thorough but all I saw was a guy selling 5 2000w for $50 Its heating approx 300l of water from 30-45 degrees, now the interesting part (as usual with my unusual projects) for a spa DIY (with help from mates) job for another mate. got two sparkie mates to do the wiring. Cousin welded a tank and i'm doing the lighting and spa side computer and pumping. I was also in charge of finding a spa heater. they cost a LOT, well too much for him. So we welded a tank, boxed it in pink batts insulation. To heat I thought a HWC element might work. thermostat goes from 30-80 degrees and is rated at 1100 micro farads so we have a cut off temp wise. In theory it will work (I think) So it this possible or will the guy just have to front up to about $600+ for a spa heater. basic plan was, power supply> RCD > thermo cut > element Cheers!	The Error Guy (14052)
1167695	2011-01-06 18:20:00	Sounds reasonable to me, but I have to confess to some added paranoia about safety when you've got electricity and bodies in water... however, your sparky mates should know the score. The whole arrangement is kinda a closed loop as far as the volume of water is concerned. Once filled it is just a case of recirculating the water. However, it'll need an occasional top-up somehow, and presumably some added chlorine or similar to keep the slimes at bay.	Paul.Cov (425)
1167696	2011-01-06 19:52:00	Got a centrifugal pump capable of moving the volume of water around at about 3-4x an hour. Also have a small filter array with chlorine tablets. Pool water will be dumped monthly (or bi monthly) for refill and re chlorinate. Only design problem we are having with the heating is where we put the coil, the tank is 24L atm.	The Error Guy (14052)
1167697	2011-01-06 20:07:00	I can see a couple of problems with the 24ltr tank ... you're going to have to make sure there's continuous water circulation at all times when the element is active ... and possibly for a few minutes after the circulating pump is switched off so that any residual heat in the element id dispersed. Not to mention a cut-out system should the pump fail ... :D ... :2cents:	SP8's (9836)
1167698	2011-01-06 21:41:00	I am not sure whether what you have done is legal. It would pay to check because if it isn't then your insurance will not pay up if there is a fire caused by the heater.	FoxyMX (5)
1167699	2011-01-06 22:41:00	Don't worry SP8's thats all factored into the design, heat will not turn on until pump is running, if the flow rate is less than value X then heat shuts off and some warning lights come up on the CP (we were thinking of a klaxon but the neighbors disagreed :p) We are still going to test how hot it gets if the heat and circulation are switched off at the same time. if its too much then i'll make a circuit the causes the floor drain solenoids to open so fresh water will be dumped into the heater. as for legality, technically we have made a constant flow hot water cylinder. as long as approved by an electrician then (as far as we know) its good to go. In principal its the same as a spa heater, only difference is price and size/efficiency. Just for interest. total cost comes to about 5k, BUT a spa of the size, shape and technical aspect was quoted at more than 8k so since we get to use it at all hours, because we built it I think its worth it!! I don't know if we are still building it yet though, the tank is the only bit we currently own and have finished. the rest is planned and budgeted but not final. still, it will look awesome.	The Error Guy (14052)
1167700	2011-01-06 23:17:00	Sounds very cool...I would love to 'build' a spa one day, al la Hanmer Springs, overflowing into a larger pool below. All set in concrete with rocks and tussocky grasses and stuff. Would be awesome. When there is $50,000 sitting around I'll do it. :lol: Kinda like this but more 'kiwi'. And the larger pool would be >2m deep, have colour changeable recessed LEDs all over the place, and a mean outdoor sound system, and a diving board, and it would be properly salt treated, not chlorine, and jessica alba would be in it.... Sorry where was I? Right. :D www.naturalspringspools.com www.naturalspringspools.com www.naturalspringspools.com	wratterus (105)
1167701	2011-01-06 23:30:00	heck wratterus that's not even hard to make! The waterfall is the easy part TBH! Pool looks like its straight 'crete with blue flexi pool paint and the spa looks like it's the same. big cost there will be heating yonder spa in its current situation because the allready heated water flows back into the pool, that meant the intake would be pool temp and require plenty of heating. The pool would also get warm too. I'd give the spa a waterfall into a small catchment so id didn't go into the main pool. On 2nd looks it seems that the spa is actually overflowing :p and the waterfall on the spa was not intended design :D 50k well yeah, that would cover it. Pool + spa 10-12k sound + lights 5k I'd say 30k at most. keep the change from ya 50k check to maintain it :stare:	The Error Guy (14052)
1167702	2011-01-06 23:36:00	keep the change from ya 50k check to maintain it :stare: Yeah exactly. :(	wratterus (105)
1167703	2011-01-06 23:48:00	Ya might just have to make do with an old cast iron bath with a fire pit underneath it and the missus blowin' bubbles thru a staw for a while wratterus ... :D	SP8's (9836)
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