Well yet another heating season is upon us. If I was smart I would have
had my heating system serviced earlier in the year, but I didn't.

My heating system is a oil fired hot water boiler that provides my house
with both domestic hot water and hot water for the baseboard heaters, three
zones. Its a reasonably new furnace so the system works well with a couple
of exceptions. Here's the three issues I have;

#1. Occassionally the furnace doesn't turn on when it should. It takes a
press of the blower's "reset" button to get it started. This is likely a
job for a furnace technician, the cleaning, repair and adjustment of the
furnace blower. I'm not touching this job.

#2. There's air in the heating system, I can hear it gurgling through the
baseboards everytime the circulators kick in. I've looked for a "bleed"
valve which I should find on one of the baseboards but to avail. The system
has an expansion tank, would this be an alternate way to deal with the air
in the system? Can I simply recharge the expansion tank and if so, to what
pressure?

#3. The heating system is sealed, the same water has been circulating about
the house for at least the three years I've lived here. How often should it
be replaced?, flushed?

I'm going to call the service company today, its getting too cold
outside to risk it failing again. Perhaps he'll answer all these questions
for me.

One last thing, has anybody with a simular heating system put in a
mixing valve for the domestic hot water? At the moment the domestic hot
water is at the same temperature as the baseboard heaters, it makes for very
very hot showers.

Any advice you can provide me with would be appreciated.

Handi