In a few months I will be getting a Rinnai Solar HWS and I would like to know if anybody has seen a Data Logger that works on their units, as Rinnai don't seem to have one.
Bit of a nerd so I like collecting data.
Solar HWS Data Logger
(10 posts) (6 voices)-
wlb
MemberI've been using temperature data logging for 30 years, starting with the old Chessell plotting z-fold chart recorders, then multi-channel hand-held Anritsu instruments, to serious Datataker products. But for cost, versatility, and shear convenience it's hard to go past the little iButton Thermochron.
Talk to David at Techbits http://www.techbits.com.au
These things are brilliant. It's a self-contained temperature logger built into a button cell battery case. You can buy plastic clips and accessories to use to attach them in various locations. You download them by inserting them into a little USB stick. You download the software and send the data to programs such as MS Excel for graphing etc.You can use them for other application too. For example, I have a eutectic fridge where the compressor and condenser unit is outside the house and when I finished the conversion several years ago, I was curious to know how often and when it cycled. So I dragged out the iButton and sat it on top of the condenser fan's grille. I wasn't interested in the air temperature, just the graph profile showing me when and for how long the compressor was running. (It was running on Black Saturday when the Bunyip fire arrived at the front gate. The fridge worked hard that day.)
I've also used it to monitor when a ski lodge was occupied. It was placed at the main heater and logged room temperature for a couple of minutes every few hours for 6 months.
Posted Thursday 13 Dec 2012 @ 2:00:58 am from IP # -
Baldrick
Memberjohnmath said:
What data did you want to capture?Well thats an excellent question. For some strange reason I expected that Solar HWS would be the same as most of the Solar PV systems. That is, its all built in and all you need to do is connect everything up.
Well I'm a nerd and I expect a lot of technology with everything I buy.
After thinking about it for awhile how does this sound:
o Collector in & out Water Temps
o Collector flow rate?
o Water Temp to gas booster (if different from collector out water temp)
o Gas booster running.
o RTCI figure that this would provide me with an idea of how much Solar Boost I'm getting, how often the Gas Boost is required and how long it runs.
Would want to be able to add these sensors with causing warranty problems.
Posted Thursday 13 Dec 2012 @ 4:22:18 am from IP # -
wlb
MemberIn that case you'll need to be looking at a serious data logger like the Datataker.
http://www.datataker.com
Unless you can find modules that will work with a PC. Temperature is easy but for flow you'll need to find a suitable sensor, and they are unlikely to be cheap. It will be an industrial component.Posted Thursday 13 Dec 2012 @ 4:35:33 am from IP # -
ghostgum
MemberI'm using Dallas 1-wire temperature sensors connected to a Linux computer to measure room, garage, roof, outside and solar air heater temperatures. A colleague had his also measuring the hot water temperature. These sensors are similar to the iButton but without battery and internal storage. The hardware to read an iButton can usually also talk to a string of these 1-wire sensors.
You can get water meters that can handle hot water and have a pulse output for about $300. I've been thinking about putting the cold water version on the output of my rain water pump, but there are other jobs to do first.
The bit I've never figured out is how each component adds to the delay in getting hot water from the tank to the tap. My parent's house had the briquette and then gas HWS backing onto the shower, giving a quick warm up time. With my Rinnai solar HWS with instantaneous gas boost and a low flow shower rose, it takes almost a minute for the water temperature to stabilise. Some is due to the copper pipes outside, some due to warming up the heat exchanger in the Rinnai gas booster, some due to warming up the plastic pipes under the house, and some for the piping in the wall and the metal tap before it comes out the spout/rose. Bosch have a thermostatic valve that diverts water around the instantaneous gas booster if the tank is is already hot.
Posted Thursday 13 Dec 2012 @ 5:21:24 am from IP # -
wlb
MemberThere are probably low cost flowmeters designed for garden use, but you would have to be prepared to sacrifice one to see what hot water did to it.
The iButton is made by Dallas. I wish they had a version that simply logged contact closure connecting each side of the case, through a resistor if necessary. That could be very useful.
Posted Thursday 13 Dec 2012 @ 5:32:28 am from IP # -
alfresco24
Membercheap flow sensors and other bits from http://www.futurlec.com/Flow_Sensor.shtml
Posted Friday 14 Dec 2012 @ 5:13:21 am from IP # -
Bushwalker
MemberAlso: http://www.seeedstudio.com/depot/-p-635.html?cPath=144_151
Hall effect, 1-30L/min, liquid temp <120C, pressure under 1.75Mpa $9.50ea
Posted Friday 14 Dec 2012 @ 6:21:55 am from IP # -
Baldrick
MemberAfter even more thinking about it:
Flow rate is not required because there is a circulation pump for the collector, I only need to know when its running (assuming its a constant flow pump).
o Collector in & out Water Temps
o Water Temp to gas booster (if different from collector out water temp)
o Gas booster running.
o RTCSo that will be:
2 (or 3) water temp sensors
2 Contacts (1 for the pump and 1 for the boost)
1 RTCThis should be a very simple system, now the hard part, does anybody have a schematic for a Rinnai system?
Posted Friday 14 Dec 2012 @ 6:43:18 am from IP #
