Sunseeker 75 calorifier thermostat

[starfire]

Sorry,
My bad.
I missed the stainless jacket bit
?

 

[plumbob]

As I’ve said in various number of my posts and in my photos that calorifier is completely clad in a stainless steel jacket.. other than cutting a reasonable amount of the stainless external cladding to gain access to the internal copper tank how do you suggest I “tuck” a new capillary bulb inside the tank?

Just had a careful look at your photo. It's astonishing to think such a great quality item has no way of accessing the cylinder itself. Unfortunately the little capillary tube is gas filled so you can't join another one to it. I'm sure you've looked but is there no way of loosening the bands that hold the s/s sheet, which must be split, to remove the old one? Your only other option is to try it on the tank outlet pipe with a cable tie but that's only going to be able to sense water temperature when an outlet is on. Last resort. Drill a hole in the stainless. It must have foam under there which you can dig out and fit the new sensor.

 

[Timeless 2]

In your original picture there is a capped off connection next to one of the immersion heaters. I would unscrew that and see if a sensor pocket and bush could be fitted into that tapping which the capillary sensor can be fitted. The sensor is only about 25mm long and 5 mm diameter