Post By WhatEverBeansNecessary
Is there any defininitive word on using a PID and insulation in conjunction?
I'm doing a rebuild of my silvia today, including adding a PID and maybe insulation. I'm getting mixed info on the topic of insulation .
I see a PID as a "learning" box and should work perfectly given then parameters. I can also see that a machine may be less capable of "shedding" excess heat when the boiler gets above optimum temp. However, surely:
1) a PID should never allow the boiler get too hot. It should raise it to max temperature at exactly the right speed to not overshoot. If it never gets too hot, why would it need to shed heat?
2) a boiler might go below temperature as the shot pours, and insulation will help warm it up faster
A properly calibrated PID should mean it won't need to shed heat ever. If it is 100%dialed in it will shoot up to the right temp.
The insulation will help heat faster and hold the heat better.
Your troubles will be making sure you can set the right parameters. Often they have an auto tune feature which will be a good starting point and dial in from there. If the PID is incorrectly calibrated then it could well over shoot the temp and take ages to cool down due to the insulation. I wouldn't be too worried though.
Unless you have a single boiler. Embodied heat in the metal boiler can mean longer flush times. But personally I prefer insulation and pid especially when sitting hot waiting for the next cup