Adding temperature probe to hot water cylinder

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nickb800

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#2471367 26-Apr-2020 08:29

Thanks - I was using Thermocouple as a general term, but I've now learnt that I meant RTD. For control I'm looking at a Hotwire thermostat (normally used for heated flooring) with a contactor for the load and a 10K RTD sensor. I have IOT stuff installed around the place but want higher reliability for hot water.

Good to see a similar approach has been broadly accurate for others.

I think a pocket/thermowell would be first choice if I have a spare threaded nipple on the cylinder, if not I'll play with putting it by the element or under the outer casing.

Kickinbac

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#2472732 28-Apr-2020 11:58

nickb800:

Thanks - I was using Thermocouple as a general term, but I've now learnt that I meant RTD. For control I'm looking at a Hotwire thermostat (normally used for heated flooring) with a contactor for the load and a 10K RTD sensor. I have IOT stuff installed around the place but want higher reliability for hot water.

Good to see a similar approach has been broadly accurate for others.

I think a pocket/thermowell would be first choice if I have a spare threaded nipple on the cylinder, if not I'll play with putting it by the element or under the outer casing.

If you need a sensor pocket let me know, I've got a few in a box leftover from a project at work. Think they are 20mm BSP. I'm working from home at the moment but can check when I'm next there.

dukezoid

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#3308533 13-Nov-2024 14:56

Kickinbac:

If you need a sensor pocket let me know, I've got a few in a box leftover from a project at work. Think they are 20mm BSP. I'm working from home at the moment but can check when I'm next there.

Sorry to dig up an old topic, looking to add in some HWC smarts. @Kickinbac still have any leftover sensor pockets I could buy off yah?

Cheers!

timbosan

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#3308536 13-Nov-2024 15:01

nickb800: Hi, I'm planning out a major house extension and thinking about how I control the electric hot water cylinder. I'd like to have it set to heat overnight, with an automatic afternoon boost if the temperature gets below a certain point. I have a peak/off-peak/night power tariff so afternoon power is cheap, but not as cheap as night power. I'd probably have a temperature threshold of 65-70C overnight (set on the elements thermostat) then perhaps 50C for the afternoon boost threshold (set on controller). Will have a tempering valve set at or below 50C so temperature at tap would remain constant.

I'm not super familiar with how water cylinders - does anyone know how I could add a temperature probe? Are there thermowells in the elements? I'd be looking at a pretty basic cylinder so wouldn't have all the extra threaded openings found on solar/wetback cylinders. Worst case would be strapping the probe on the outlet nipple, but I'd imagine the temperature would fluctuate depending on whether hot water is being drawn or not.

Thanks

I have recently installed a heat-pump HWC and it displays the temp on the display (along with the menu for setting the timer, temp, etc.). Perhaps hooking into that may be easier than physically trying to measure the temp? But would mean changing the cylinder - depends on how major your renovations are!

Kickinbac

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#3309499 15-Nov-2024 23:04

dukezoid:
Kickinbac:

If you need a sensor pocket let me know, I've got a few in a box leftover from a project at work. Think they are 20mm BSP. I'm working from home at the moment but can check when I'm next there.

Sorry to dig up an old topic, looking to add in some HWC smarts. @Kickinbac still have any leftover sensor pockets I could buy off yah?

Cheers!

I have one spare! PM me if you want it and we can sort it.

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