Temperature of hot water

way forward

Hi
Have solar installed and its heating hot water. Have anybody came across a way to know what temp is in cylinder . Just if you wanted to have a shower in morning is there any way of checking temp
Thanks

Gumbo

way forward wrote: »

Hi
Have solar installed and its heating hot water. Have anybody came across a way to know what temp is in cylinder . Just if you wanted to have a shower in morning is there any way of checking temp
Thanks

I’ve been chasing this myself as I have an eddi.
Sometimes during winter, not a lot gets diverted but enough to heat for a shower.

I’ve resorted to manual method of putting my hand on the top pipe that leaves the cylinder. That pipe is directly touching the water in the cylinder, so if that’s hot, inside is scalding. If that’s warm, inside is hot etc

Think of it like a spoon in a cup of boiling water. Think of how the spoon heats up.

db

Do you not have a sensor at the top of the tank to give you the temperature?

graememk

You can get a thermometer that can be mounted into the tank. My dad has one on his.

If it's a copper tank with foam insulation you could get this and push it under the insulation at the top.

https://www.amazon.co.uk/Thlevel-Thermometer-Temperature-External-Refrigerator/dp/B07TY6HRL4/ref=mp_s_a_1_4?dchild=1&keywords=thermometer+with+probe&qid=1619074600&sprefix=themometer+with+pro&sr=8-4

Or zip tie it to the pipe coming out but allow a few degrees as Gumbo says. As soon as you turn water on it will shoot up to the actual temperature

mun1

I’m using 3 of these sensors to see if i can tell how much hot water is in the tank.
One is placed on the pipe coming out of the top of the tank.
One is on the middle pipe (mid way down the tank) and one is just for ambient temperature in the hot press.

Been looking at this the past 2 weeks and it looks like the one attached to the middle pipe gives a good indication when you are running out of hot water.

I used to try to judge it by the power consumed so if the tank got 7-8kw in a day it would be full of hot water (the iboost cuts out)
Get about 35-40 mins of hot water for showers out of a full tank.

Duine_Eigin

Gumbo wrote: »

I’ve been chasing this myself as I have an eddi.
Sometimes during winter, not a lot gets diverted but enough to heat for a shower.

I’ve resorted to manual method of putting my hand on the top pipe that leaves the cylinder. That pipe is directly touching the water in the cylinder, so if that’s hot, inside is scalding. If that’s warm, inside is hot etc

Think of it like a spoon in a cup of boiling water. Think of how the spoon heats up.

You could get the optional relay board for the eddi which will give you the temp in the tank. You need a PT1000 temperature probe too, I got mine on amazon. The temp is shown on the screen of the eddi and also in the app (if you have the myenergi hub installed). It's a simple install; just a matter of opening the eddi, fitting the relay board and plugging in the connector. It will also give you additional relay outputs for the eddi to control devices other than the immersion.

https://myenergi.com/product/eddi-relay-sensor-board/

way forward

Hi
Dont have a eddie or a sensor at top of tank . Will take a look at amazon.

Gumbo

db wrote: »

Do you not have a sensor at the top of the tank to give you the temperature?

I don’t.

Gumbo

Duine_Eigin wrote: »

You could get the optional relay board for the eddi which will give you the temp in the tank. You need a PT1000 temperature probe too, I got mine on amazon. The temp is shown on the screen of the eddi and also in the app (if you have the myenergi hub installed). It's a simple install; just a matter of opening the eddi, fitting the relay board and plugging in the connector. It will also give you additional relay outputs for the eddi to control devices other than the immersion.

https://myenergi.com/product/eddi-relay-sensor-board/

Cheers. Seen that but don’t have the hub either.
It may be something to consider if I ever change my car charger to a zappi as I’d require the hub at that stage.

way forward

db wrote: »

Do you not have a sensor at the top of the tank to give you the temperature?

What is the sensor at top of tank ?

championc

way forward wrote: »

What is the sensor at top of tank ?

Normally some sort of probe, touching the copper cylinder, and relaying the information to a digital readout

Ha Long Bay

Sorry for bumping an old thread just wondering have many fitted the relay board and thermostat sensor to their Eddi?

Recently replaced the old small cylinder to a new Joule Cyclone and would like to get accurate temperature information.

silver_sky

https://www.boards.ie/discussion/comment/120449519#Comment_120449519

I have, it's easy enough to do. Just a little fiddly trying to seat the ribbon cable for the board. A tweezers would be a help.

Ha Long Bay

https://www.boards.ie/discussion/comment/120449589#Comment_120449589

Thanks for the reply. Do you find it was a good addition to the setup? Board and probe are relatively cheap so thinking it could be useful for automation.

silver_sky

It's interesting having the information but haven't found much other use for it yet.

Ha Long Bay

https://www.boards.ie/discussion/comment/120449629#Comment_120449629

My use case would be to know if the water is hot enough the next morning to have a shower or do I need to boost via the Eddi or Gas. At the moment its a bit more manual by running the hot tap to check.

Jonathan

https://www.boards.ie/discussion/comment/120449747#Comment_120449747

I'm not using the Eddi relay board, but pulling similar information from my Solar Thermal controller. I have a daily hot water boost to heat the water to a set temperature in HA (she increases the temp slider on the days she's washing her hair).

unkel

What solar thermal controller to you have @Jonathan? I have a Kingspan SC400 that also shows me top cylinder temp, bottom cylinder temp and roof collector temp. Would love to get that info into home assistant

Jonathan

https://www.boards.ie/discussion/comment/120452388#Comment_120452388

Resol DeltaSol BS/3. I have the VBus output connected to a Raspberry Pi Zero.

graememk

https://www.boards.ie/discussion/comment/120452957#Comment_120452957

Is the vbus hard to setup? Mine has vbus too. Once I figured out it was a rebadge.

Jonathan

https://www.boards.ie/discussion/comment/120453234#Comment_120453234

VBus is similar to RS485 in that is is differential, but it uses different voltage levels so you need some circuitry to convert to appropriate levels. I'd recommending having a look at the Resol controller first. It seems some of the controllers output TTL level and use a different board to convert to VBus levels. My controller is newer (older?) and only outputs VBus levels, so I used this to convert. There are other circuit examples here and here. Once you have the hardware sorted, you are ar muin na muice.

As for the parsing side of it, because I used the rpi0 board, I used pyvbus to parse and serve the results as JSON over HTTP (this predated my use of HA). If I was starting again I'd push over MQTT but the REST sensor in HA integrates with this just as well.

graememk

https://www.boards.ie/discussion/comment/120453283#Comment_120453283

Thanks for the that,

Looks like mine is a sonnenkraft SKSC2. If I stick a multimeter on it, I should be able to see if it's TTL or not.

I do have rs485 boards but by they sounds of it I don't think I can use that directly

Jonathan

https://www.boards.ie/discussion/comment/120453710#Comment_120453710

Looks like a rebadged DeltaSol CS/2. Sonnenkraft were clearly very imaginative in their new name. 😂

graememk

https://www.boards.ie/discussion/comment/120454040#Comment_120454040

Turtles all the way down, the actual label is pro solar ps c104 😂

graememk

https://www.boards.ie/discussion/comment/120454052#Comment_120454052

Good job I took the cover off..

No vbus terminal.

Also no voltage on it either, solar tubes have been in since.. 07/08ish

Jonathan

https://www.boards.ie/discussion/comment/120457199#Comment_120457199

Anything on the back of the board?

graememk

https://www.boards.ie/discussion/comment/120457219#Comment_120457219

No time today for a full disassembly, I'll have a check another time,

oaklands

https://www.boards.ie/discussion/comment/120457310#Comment_120457310

If all else fails, you could look into tapping the voltage levels of the PT1000s at the terminals using an ESP32's ADC or similar & report values over WiFi.

You would just have to calibrate the readings once against the water temp in the tank or if you could check how the resistor divider is laid out on the existing PCB you could be more confident of the values.....

However, you would want to be sure of what you were doing. I suspect the warranty is long gone.😁

graememk

https://www.boards.ie/discussion/comment/120457909#Comment_120457909

I do have one shoved under the insulation at the top (the ds18b20 ones) and using it to control pump on the stove too.

I did hope to pull run time from it to calculate kwh too.

No stranger to pulling electronics apart.

zarker

https://www.boards.ie/discussion/comment/120452388#Comment_120452388

Hello there! I too have an sc400 and would love to be able to push this info into Home Assistant.

Have you had any luck in doing this yourself? Many thanks!

championc

https://www.boards.ie/discussion/comment/121140849#Comment_121140849

Is it the big SC400 which has the SD Card in the side ? If so, that's the rebadged Steca TR0604 and has an RS232 which I have connected to a Raspberry Pi and sends the data via MQTT to my main Node-Red