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Digging up an old thread I thought a few of you might like this gadget.Quote:
Originally Posted by MrFixIt
http://www.rinnai.com.au/hotwater/ho...?whs=home&pg=6
I'd like to know the cost of them - certainly cheaper to install one of these rather than two hot water heaters and there's no wasted water waiting for the water to heat up.
What the? Probably worth reading complete posts - installing two of these is what the latter part of the discussion has been about . . . :o))Quote:
Originally Posted by null & void
I have had a Rinnai 2400 for 8 years and it is superb and saved a fortune on the electric Off-peak storage HWS we had before that - and we never run out of HW.
We are doing renovations and I had though of adding a new smaller one nearer the new ensuite, but instead used insulated pipe then additionally insulated using zip on black foam all the way.
A little loss from water in the pipe (but applies to all types as has been said), but works very well.
Huh, I'm referring to the Smartstart below the gas hotwater system in the picture - I've never seen it mentioned in the numerous gas hot water discussions here.Quote:
Originally Posted by Bloss
Does away with the need for two hot water systems by preheating the hot water in the pipes without wasting any water. So turn on the hot water tap and you have hot water. In my kitchen I can waste almost a minute of water before the water coming out is hot, and it's a common compliant from people with instantaneous gas systems.
Aaah - should take my own advice and read the full article eh! :doh: :doh: :doh:Quote:
Originally Posted by null & void
Looks an OK idea, but as has been said above this is a non-issue really. The water in the pipes will be cold for all HWS not just instantaneous ones and the longer the run the more there will be sitting in the pipes hot when you turn off the tap too.
This is a trivial amount of water relative to the volumes most households use - 12mm or 19mm pipes hold little over the distances in most houses and this seems an expensive way to save a small amount of water.
If the user has already done the big saving things such as dual flush toilets, aerated outlets on taps, water-saving shower heads and made efficient all their garden and outside use (drippers, grey water etc) then this might be a further step, but will use more energy too - so more greenhouse gas and higher cost.
People tend to forget quickly what happened with their former system - and often the new one is in a different location. The first use of hot water takes time to clear the cold then less time on each subsequent use within a reasonable time.
That's why the recommendation for all HW systems is that they be sited as close to the kitchen as possible - that's where most hot water is used most often (few use HW in the laundry now). Since most blokes use the kitchen not all that much they tend to think the shower is more important.
Better insulated pipes improves the perceived re-heat time after the first use, but has no effect on the heating itself. In cold climates insulating inlet pipes can help a little if the under-house temperatures are very cold and the pipes are exposed to the air.
In a place like Canberra where the inlet water temperature can be around 12 degrees or less in winter so the Rinnai would be working harder to deliver at full capacity then - in summer the inlet temp can be up to 20 - so insulation and closeness to most used outlet becomes even more important.
IMHO a gimmick really, but I should have read it more closely before posting last time.
Interesting idea though NOT VERY PRACTICAL!Quote:
Originally Posted by null & void
This will now waste gas heating ALL the WATER in ALL of the hot water reciculating line, NOT just the water between the heater and the tap that is turned on.
This NOW also means that ALL the water existing in the pipe is hot. When the hot water is turned off, ALL the water in the reciculating line cools down, waiting to be reheated AGAIN :doh: The priciple behind this provides a miniscule "storage" HWS which we are attempting to avoid, this is the reason the Instant HWS are being used.
In (my guess) 90% of the time, the cold water within the pipe is "used" within the mix of hot water for the purpose for which the tap is turned on.
The only way this device could be considered practical is if the recirculation is between the tap in use and the heater. This would mean a SEPARATE recirculatory line for EACH tap, NOT a ring main, obviously NOT practical :o
We have just moved into our new home (2 weeks ago) and I'm ready to rip the bloddy thing off the wall (Rinnai Infinity 26). The water pressure is useless. I ripped the water restrictors off the taps to increase the flow from a tricle (you couldnt even rinse you hair of shampoo) but its still crap. The actual water presure of the cold water is great but I'm assuming the Instantaneous system needed to reduce the pressure in order to heat it properly. I'm not one for water saving or more efficient HWS just gimme a decent shower!
End of Rant!
I will be talking to a plumber to see what can be done about is as we installed 2 shower heads in one shower so we could both have a shower at the same time. It turns out it was a waste because of the water pressure only one tap can be going at any one time.
just on the heat pump type mcblurter there is a brand on the market call Quantam Hot Water check em www.quantumenergy.com.au out I think from memory they have an excellent operational ranges they are expensive but from what I understand they are the most energy efficient on the market
Sound like you have a pipe sizing problem........Quote:
Originally Posted by Tubby2
How old is the house?
Tubby2, how did you go regarding this, I am currently investigating instant gas hot water, and this is one of the ones I was looking at gettingQuote:
We have just moved into our new home (2 weeks ago) and I'm ready to rip the bloddy thing off the wall (Rinnai Infinity 26). The water pressure is useless. I ripped the water restrictors off the taps to increase the flow from a tricle (you couldnt even rinse you hair of shampoo) but its still crap. The actual water presure of the cold water is great but I'm assuming the Instantaneous system needed to reduce the pressure in order to heat it properly. I'm not one for water saving or more efficient HWS just gimme a decent shower!