Simon Mitchell wrote:

> as recommended by Valrhona) to begin the tempering process again, it
> becomes thick and somewhat lumpy.
>
> I have strained out the lumps and used it ok. But the lumps reoccur
> without fail each time the chocolate in my tempering vat is allowed
to
> cool and set after use and then is reheated to 58 degs.
>
> I had never encountered this problem before using the hairdryer, and
> have encountered it every time since.
>
> Any ideas, suggestions or explanations?
>
> Simon

58 degree C is too high to melt any forms of chocolate for tempering.
No wonder you got lumping problems .
It should be only in the range of 45-50 degree C.
A sair dryer is only used to soften chocolate that has started to set
after being tempered not to use it for melting chocolate.
Roy