Solo 40 Aquastat question

[lawandorder]

My solo 40 has two aquastats in the rear of the unit. One is next to the junction box which i believe is for the overheat loop. The second is attahched to a pipe coming from the relief valve. The overheat aquastat is a l4008 and is set at 160 the other is a l4006 which is set at 190 any idea if these are set correctly??? If not what should they be set at. When I look at the Tarm manual it shows the one overheat aquastat but say it should be set at 200. Not sure if that is why i have second aquastat at the relief valve. Any ideas would be great...

 

[Chris Hoskin]

The over-heat aquastat (mounted on the side of the boiler) should be set at 200 and dumps heat into your larges zone should boiler temp ever get that high. The aquastat at the back of the boiler is likely the unit that turns on the circ pump - this should be set at 165. If, on the other hand, this aquastat is used to lock-out a fossil fuel boiler, it is normally set at 140.

 

[lawandorder]

thanks chris as always...

 

[Birdman]

uh... I think my issue may be related to this post. I am noticing now that I am using my Tarm Solo 40 for the second year and my wood is much drier.... that the gauge on the front of the Tarm panel is reading 94 C. My aquastat is set at 205. Is this a bad thing? I have one other gauge... it is attached to the oil boiler( I am set up parrallel). It reads 195 F when no zones are calling. Are these temps too high? What is the hottest temp I want for hot water going through my pex?

 

[twitch]

I'm using 1 inch Viega FostaPEX (pex-al-pex) in my system and the only thing I could find was that it was good to 100 psi at 180 °F and 80 psi at 200 °F. I know all pex does not have the same characteristics, but could be ballpark.