I was just advised by an HVAC person than my hot water boiler heating system should be drained and refilled and air purged at least twice a year. I do not understand why. It originally had glycol in the system and still has some (much has been replaced with makeup water as parts were replaced over the last 4 years). I do not hear any air in the zones as they operate and the Taco air vent or separator seems to work, meaning it is not leaking and not corroded. All zones seem to heat properly. Is this a normal maintenance procedure?

Hi, I have a unique issue here. The controls are L8148A aquastat and R4184D1027 Primary control both are Honeywell. The boiler doesn't fire by itself all the time. I took the igniter out and showed a professional and he said it was good. I checked the voltage leading from the aquastat to the primary and when it's trying to light there is 120 VAC. The circulating pump pumps the water fine, and the jet blows fuel perfectly. When I check for voltage to the igniter it reads 0, but EVERYTHING ELSE works perfectly. Sometimes, usually 1st thing in the AM, or after being off all day I can hit the reset and have it light and occasionally it'll re-ignite when it needs 2 or 3 times...nothing more. So, I hit it with a torch and light it that way. Not smart, but a little desperate. If someone could point me in the right direction I'd REALLY appreciate it!!