Solar thermal - servicing / upgrades (Cork metropolitan area)

donal.hunt

Any recommendations for servicing an existing solar thermal installation (solareg ii controller + grundfos pump) for Cork city area?

Also interested in recommendations for company to upgrade the existing controller so I can collect data from the system remotely (vbus seems to be the way to go). Is that something one could do themselves? Recommendations on a better controller welcomed (will likely be installing solar PV in near future too so if there is a particular platform that works well, will likely try and stay consistent).

Thanks!

TerraSolis

I retrofitted the SR208C Wifi controller from Aliexpress and have it connected to Home Assistant via Tuya. Only complaint is the SR208C controller doesn't leave a lot of room for the sensor cables coming in, so it's difficult to get the sensor cables in neatly. Still playing with the interface - need to tidy it up a bit.

https://www.aliexpress.com/item/1005005311362138.html?spm=a2g0o.productlist.main.17.42982d3c1gG4Qx&algo_pvid=12e84d04-0d54-4e06-9abd-a59dc20054e0&algo_exp_id=12e84d04-0d54-4e06-9abd-a59dc20054e0-8&pdp_npi=4%40dis%21EUR%21157.27%2173.92%21%21%211210.69%21%21%40210318b816942501645523997e67f6%2112000032585734436%21sea%21IE%212664658932%21S&curPageLogUid=HsG5RtYTaLLy

graememk

https://www.boards.ie/discussion/comment/121088488#Comment_121088488

I'm gonna look into this too. Could be a nice upgrade.

TerraSolis

https://www.boards.ie/discussion/comment/121089597#Comment_121089597

Cool - let me know if I can be of any help. Straight forward enough though. One thing to double check is the type of temperature sensor you currently have on your system. I had to swap one NTC on the panels themselves for a PT1000. Even easier if I didn't have to do that.

randombar

https://www.boards.ie/discussion/comment/121096337#Comment_121096337

I've a kingspan sc100 controller. Love the idea of this project to be honest, any idea if it's a simple swap out for my controller?

@donal.hunt I've a guy that serviced mine in cork if you want to send me a PM

Jonathan

https://www.boards.ie/discussion/comment/121096469#Comment_121096469

If it's a rebranded Resol, then you probably have three PT1000 sensors. If your pump station is near your cylinder it should be easy enough to replace the two in the cylinder pockets with NTC sensors.

@TerraSolis I am assuming that the PT1000 is for the collector?

TerraSolis

https://www.boards.ie/discussion/comment/121096743#Comment_121096743

The SR208C controller linked works off PT1000 X2 (or X3 if you want a temperature probe both at the top and the bottom of the tank).

My previous set up had 2 PT1000 in the cylinder and one NTC in the collectors. Had to swap the NTC in the collectors for the PT1000 that came with the SR208C.

If you already have PT1000 in the collectors it's a very easy swap for nearly any controller. So sounds like it could be a straight swap for the Kingspan.

If you're going for it, make sure it's clearly marked as the WIFI version as there is a version without WIFI.

randombar

https://www.boards.ie/discussion/comment/121096825#Comment_121096825

I have a collector probe all right, any idea how to tell if it's a PT1000 or an NTC without taking roof apart or crawling through attics?

graememk

https://www.boards.ie/discussion/comment/121096853#Comment_121096853

https://www.manualslib.com/manual/1057777/Kingspan-Sc100.html?page=11#manual

Looks like it uses pt1000 sensors

@TerraSolis can the 3 sensors on that aliexpress one be pt1000? it seems that it comes with 1 pt1000 and 2 ntc ones

TerraSolis

https://www.boards.ie/discussion/comment/121096853#Comment_121096853

It's often written on the wires, or you can read the temperature, disconnect the sensor really quick and read the resistance across it with a multimeter and compare that to NTC / PT1000 graphs. Alternatively, a quick google of the Kingspan sc100 suggests it only takes PT1000s.

graememk

One more question, @TerraSolis

Its running tuya, It could be running an esp chip, did you see one when you had it open?

While I can deal with tuya, I am trying my very best to keep everything local. (eg flash it with tasmota or esphome!)

TerraSolis

https://www.boards.ie/discussion/comment/121096908#Comment_121096908

ESP will be my next learning adventure :) It's not something I've sat down with yet.

I can have a look and see if there's anything obvious when I get home later in the week. I do have it local though!

Connected to home assistant via the Local Tuya integration. A bit of a balls to set up, but runs grand with no cloud dependency.

graememk

Had a quick skim of the manual and the WiFi version seems to communicate via rs485.

Likely easier just to live with the tuya service

TerraSolis

https://www.boards.ie/discussion/comment/121096825#Comment_121096825

@graememk @randombar apologies I got that wrong/missremembered. The SR208C does indeed come with 2 NTC and one PT1000. I just remembered I actually had to swap all three sensors. It needs PT1000 in the collectors and 2 NTC for the cylinder. So you will have to swap the cylinder probes on the Kingspan controller (but thankfully not the collector probes).

I got confused because my original solar controller was the inverse (NTC in the collector and PT1000s in the cylinder - twas unfortunate!).