contact between tank thermostat and copper hot water tank

[pushrod]

Hi, I want to improve the thermal contact between the hot water tank and the thermostat. The old one had some sort of silvery paste. Anyone know what it is and where to get it - or can i use any high melting point grease?

would the heat sink pastes for computers do the same job?

cheers

 

[happyflyer]

Why on earth do you need to do this, domestic hot water temperature control is the crudest control on the plant, it has a band of plus or minus about 5 Deg C set the thermostat at 60 Deg C could be 65 could be 55, the DHW strap on stats are mainly bi-metallic some paraffin, why do YOU need to be so accurate. High melting point grease will do or PC Processor grease will do.

 

[mjamie]

Heat conducting paste, I've got tub lying in van which was left over from sensors at an oil processing plant. Danfoss used to supply small sachet of paste with stats but can't say I've received one in a good while. Have a search online, should be easy enough to find if you're needing

 

[happyflyer]

Heat conducting paste, I've got tub lying in van which was left over from sensors at an oil processing plant. Danfoss used to supply small sachet of paste with stats but can't say I've received one in a good while. Have a search online, should be easy enough to find if you're needing

Send him some in the post, " handle with care don't squeeze" postman pat will wonder what the hell it is BOOOOM

 

[pushrod]

Problem is hysteresis (i think it's called) the delay between heating and switching, when just the hot water is on. By the time the thermostat switches it off, the boiler has overshot the temperature quite considerably so the hot water is too hot. (turning the the HWT thermostat down a touch means it often won't switch the water on in the morning until it is cooler than wanted). Problem not so noticeable with both CH and HW on, as water from boiler being shared by diverter valve. The old one (a danfoss) worked fine with the thermal paste so just thought sticking some more on would improve things.

Cheers

 

[happyflyer]

You are right it is called hysteresis but that's not what your problem is the the stat is crap, too much differential another sort of hysteresis, these stats are crude I would change it and hope you get a better one???

Tony