I have a 3 story house with old galvanized heating piping and hotwater heat system. Aquastat just replaced by pumber, also new bladder expansion tank set at 15psi. Today I checked the guages and the pressure was 20. Only change I had made was to increase the temp so that the boiler cycled between 190 and 160 degrees F, since we are having a cold snap and the house wasn't getting warm enough. I drained off some water through the over pressure release valve and now the pressure fluctuates with the temp. At its lowest it is 10 and highest is 16. There is an adjustable valve on the water intake that the plumber said he adjusted. Another plumber from the same firm said I should turn off the water intake all together to get a stable pressure since the intake valves don't work all that well. Questions: With the new bladder tank should the pressure fluctuate at all or should it stay at the 15 mark since that is what the bladder tank is supposed to be at? Does pressure normally fluctuate as described with the temperature? Should the water intake be off all together or should that darn intake valve pressure controller work better. Thanks for your help, Luke

With the onset of this nasty cold weather it seems like my system will keep the house at the current temp but won't go up. Hi limit 180 Low limit 165 Differential 15 Should I raise my limits up or lower the differential to 10 or 5 on these frigid days ? Thanks