[mark15]

apologies if this has been asked before but im fitting a corwoods heater tomoz... does hot water affect the tds reading?

[Jonny 87]

Yes. It raises it.

It's a false reading though. Measure the water cold and that is it's true reading.

[LWC]

Yes. It raises it.

It's a false reading though. Measure the water cold and that is it's true reading.

Didnt know that! ... you sure you aint got TDS meter set to "temp" 

[Jonny 87]

Yes. It raises it.

It's a false reading though. Measure the water cold and that is it's true reading.

Didnt know that! ... you sure you aint got TDS meter set to "temp" 

Haha, no I havnt.

Test it out yourself. Turn your tap on at home and take a TDS reading. Then turn your hot tap on and take a reading of that. It's always higher. But if you pour the hot water in a cup and let it cool, you will see the TDS drop too.

[slap bash]

The re is no way tds can rise in hot water it jut not possible as were would the  parts come from in the hot water.The only explanation might be, the were trapped on the boiler element and dissolved with the hot water.But then the would not undissolved solids.

[slap bash]

In the case of hot tap water all the undissolved solids are trapped in your heating system in the form of scale.When heating water should do the same in the heating of pure if the water was not 100 % PURE in the first pace so reducing tds. But it would not be so you would have a problem with cleaning glass.

[Jonny 87]

The re is no way tds can rise in hot water it jut not possible as were would the  parts come from in the hot water.The only explanation might be, the were trapped on the boiler element and dissolved with the hot water.But then the would not undissolved solids.

Hot water does something to the TDS readers. It doesn't actually raise the TDS it just reads higher, and then when it cools down it goes back to original TDS.