Temperature differences on equipment

[martyjhuebs]

I am running a insulated keg mash tun with a thermometer on the outside. I also run a RIMS tube to maintain the temperature. Last brew day my RIMS was registering a significant temp difference than my mash tun, I'm talking 142 on the RIMS and 154 on the mash tun. Has anyone experienced this before?

 

[FourSwitch]

are the temps stable with the system dry and at room temp? (if the thermistor is bad it should be 12 degrees out still at room temp) might just be a thermistor that needs replacement. other thoughts are if you took that measurement right at the start of mash and the rims tube was still room temp so you are losing a few degrees to warming the metal of the rims. but most likely its a thermistor thing

 

[TLaffey]

I am running a insulated keg mash tun with a thermometer on the outside. I also run a RIMS tube to maintain the temperature. Last brew day my RIMS was registering a significant temp difference than my mash tun, I'm talking 142 on the RIMS and 154 on the mash tun. Has anyone experienced this before?

I have about a 4 degree F offset between mash tun (measured with a thermapen) and the RIMS controller temp. The controller has a setting for this offset, so I made that adjustment and all is well. Assuming you have an accurate thermometer in the tun, go with that and adjust your RIMS to maintain your mash temp.

 

[LarMoeCur]

Are you using an RTD on the RIMS? A few brews back I had a cable on my RTD probe that shorted out causing weird readings. Super easy to check with a voltmeter. I had to resolder the connections. They are super fragile.

 

[martyjhuebs]

Well... I checked my thermocouple with ice water and it read 33.2F. I'm thinking my my mash tun may be off. I've always taken it for accurate because it is the same as the ambient temperature when I start brewing.