Alaxa Water meter for Central Heating

[joba]

Hello guys, totally fresh and new in this forum, so be a bit gentle with me [:I]

Im thinking of some monitoring of my central heating system. Where does the heat come from (thermal solar or central heating system) and where is it going to (living, first floor, or just the non-isolated pipes). The purpose of the project is even beyond that (also balancing of the central heating system with a "speksteenkachel") but for the moment thats not the issue.

I figured out that with a water meter and with 2 temperature sensors you can calculate the consumption of energy over a certain part of a cv-circuit. Or you can calculate the added energy by the thermal solar system or the central heater.

My question for you guys: has anyone tried this? What will be the biggest issues to solve?

My guess: one alaxa watermeter per cv-circuit (we have two main circuits), a couple of thermosensors (I counted 7 interesting points), some stuff for countering the pulses and getting the temperatures, a cheap (homemade?) datalogger, and im ready to go!

Any ideas?

[Digit]

For collecting data you could consider a HA7Net (http://embeddeddatasystems.com/page/EDS/PROD/HA/HA7Net)

With a DS2423 to count pulses from the water meter(s) and 1-wire temp sensors. I use that setup.

Although to get accurate energy calculations i think you'll need temp sensors <b>inside</b> the pipes, not fitted on the outside of the pipes. That's the challenge i think.

[joba]

I think indeed that i need to put the sensors in the pipes. Not much found so far on the internet for doing this. Of course there are temperature sensors for central heating systems, but im not sure how difficult it will be to combine this with the logging system. For logging system HA7net is a good candidate.



Als je een hamer hebt lijkt elk probleem een spijker

[iamjwk]

I have put the sensors on the copper tubes. First cleaned the location where I wanted to stick the sensor, then used <u>computer processor heat transfer paste</u> & metal tape to bound the sensor to the tube. Then covered it with insulation.

Even in the process industry it is very common to use a thermowell to stick a temperature probe in; its in a pocket in the pipeline and no direct contact with the liquid.

This way I am monitoring my central heating (floor heating in/out. Hot water, boiler in/out temp, etc).

Jan-Willem

[Herbus]

Jan-Willem,

Can you tell something more about the hard- and software? What sensors, transmitters and logging are you using for this solution.
Seems an interesting solution to manage power consumption.

Grz

Jos

[iamjwk]

Herbus; be aware I am just a beginner!

Last year bought a RFXCOM receiver and some sensors to play around. This month started to get serious with home automation. Screened ready available software and came to homeseer; programmed a script to store received data in a ms-access database. Then a website displays some charts. Spend a lot of time reading this week to make the best hardware choice from all systems available. Coming months I can gradually extend the devices/switches etc. Think will buy Xanura stuff. But first priority is energy monitoring as for the first time since 4 years we had to pay additionally to the energy company; 320 euro's (could have bought some nice devices for it).

Coming week I will probably buy the RFXCOM transmitter.

But you can find a lot of info on this forum, the RFXCOM.com website, and in the homeseer.com forum. And of course bwired.nl

Jan-Willem

[Herbus]

Jan-Willem,

Seems we are at the same stage. Im starting with domotica right now. Has also chosen Homeseer as the central sw-engine. Looking at some of the domotica-experts on this forum we have a long way to go.[:)]
What kind of sensors have you attached on the tubes?

Jos

[Bwired]

check this also this topic http://www.domoticaforum.eu/topic.asp?TOPIC_ID=992
regards Pieter

[iamjwk]

RFXCOM External Water Tight Temperature sensor Order code: 60014. This coupled to a RFXsensor. Signal received by the receiver. For room temperature measurements I use the Oregon devices (even just bought the "weegschaal"), which are also received by the RFXCOM receiver. I also discovered it receives X10 codes from a cheap remote control with 3 switches from the brand Desa (found it at the shop "onderdelenhuis").

http://www.rfxcom.com/sensors.htm#Additional

Jan-Willem

[Bwired]

This is the Oregon THC138 It has a separate temp-sensor and can be installed easy on pipes, cooler, fridge etc. The nice thing about it that you can read the temp also on the digital display and the RFXcom receiver can receive these sensors. Much easier then 1-wire, I have 6 of these installed right now.

[iamjwk]

Bwired, where can you get these? Searched for these in several stores but could not find them.

And I agree, they are much simpler and cheaper. I am collecting them and just discovered somebody nearby has bought them today and I receive them for free [:D]

[Bwired]

http://www.ukweathershop.co.uk
not available in the Netherlands yet, shipping is only 5 pound.

[iamjwk]

Ok. will try that.

Jan-Willem