View Full Version : Aquastat setting

11-06-2007, 05:19 PM
I recently purchased a 1200 sq ft. ranch style house with an old Crane 70 Series oil fired boiler. I'm probably going to replace it down the road. In the meantime, I want to get it running as efficiently as possible. I did have an oil company clean the boiler and the tech said that it was running well for an older boiler.

My question concerns the aquastat setting. The aquastat is a Honeywell 8124. The settings are hi 180, lo 160, and differential 20. The boiler originally had a tankless coil for heating hot water; however, now there is a separately gas fired hot water tank.

The system seems to occasionally (every 15-30 minutes) come on for a minute or two and then shut off. It also seems to take a long time for the system to come to temp. I know the aquastats can vary over time. I can't confirm the hi temp as the boiler temp guage doesn't seem to working.

I have a few questions:
1) Since the boiler no longer is supplying hot water, can the low setting be reduced;
2) Should I raise the hi setting so that the system can run a little higher which should reduce cycling and heat up time.
3) Since the temp guage doesn't seem to be working, should I attempt to take the water temp from the water in the pipes. I know it it gets colder as it goes through the system but at least I can get tell if it is any where near the hi temp.

Thanks for your help.