Personal background - 10 yrs Navy Electronics Technician + 25 yrs trash to energy power plant. Good working knowledge of electro-mechanical, digital and hydronic systems.
Built the house in '96, been here ever since. Appliances are all vintage with very few repairs / replacements, so most everything is 28.5 years old.
Burnham oil boiler with internal DHW coil, Beckett burner, Honeywell L 8124 A/C triple aqua stat set to 150 low, 10 diff, 180 hi limit and 2 zones of baseboard heat. This works well for us 24/7/365. Oil does the DHW and shoulder season heat with T-stats set to 69. When below 40 deg we have the wood stove going. Typical oil usage is about 1 gpd. During extreme cold snaps (teens and below) the oil will help out as needed.
Everything has been normal so far this fall and winter, although I have heard a bit of buzzing/vibrating noise from the circulator relay at times. It has a little counterweight on it that may be causing the noise, but the relay contacts themselves have not been chattering.
Recently went through a warm spell for several days in SE CT so the stove was cold and we were on oil. No issues.
No issues with my shower Thurs morning at 0400 but wifey said hers was a bit chilly at 0600. She got home at 1715 to a house at 58 deg with high winds and a cold front moving in and said WTF? and lit the wood stove. I got home at 1900 and heard the bad news. Investigation reveals the oil boiler stone cold at 70 with the fire eye tripped. Reset fire eye and it took off ok, heated up ok, got above setpoint, then circulator started ok since the house was still at 64 but it continued to fire to over 200 when I shut it down.
Cycled the low limit setting. It clicks on and off.
Cycled the hi limit setting. It doesn't click on/off, so it seems like it's stuck on and allowing the boiler to overfire to a high temp.
Opened breaker, pulled knobs off aqua stat, removed 3 screws, removed cover, found white crusties, (evidence of slight water contamination from a slightly leaky DHW fitting) and a brown sticky substance (solder resin?). Cleaned this up with electrical contact cleaner. Looks brand new again. Re-assembled. Low limit seems to work ok. High limit seems way off, it still wanted to overfire to 200 deg. Shut it off for the night.
Turned it on and watched everything as she showered Fri morning. Low limit / diff seem to be working ok. Still not sure if high limit is AFU / reliable since the house is warm due to wood stove.
Question - Replace 28.5 year old Honeywell L 8124 A/C triple aqua stat with identical replacement? Maybe more reliable. Maybe longer lasting but looks like about $100 more.
What to use? Replace with newer digital/electronic version? Apparently, Honeywell is now going by Resedio. What's up with the name change? New ownership or what? Are they still any good?
What's better, old school electro-mechanical or new school digital/electronic. Probably got my $$$ worth out of a 28.5 yrs unit but what should I replace it with?
Built the house in '96, been here ever since. Appliances are all vintage with very few repairs / replacements, so most everything is 28.5 years old.
Burnham oil boiler with internal DHW coil, Beckett burner, Honeywell L 8124 A/C triple aqua stat set to 150 low, 10 diff, 180 hi limit and 2 zones of baseboard heat. This works well for us 24/7/365. Oil does the DHW and shoulder season heat with T-stats set to 69. When below 40 deg we have the wood stove going. Typical oil usage is about 1 gpd. During extreme cold snaps (teens and below) the oil will help out as needed.
Everything has been normal so far this fall and winter, although I have heard a bit of buzzing/vibrating noise from the circulator relay at times. It has a little counterweight on it that may be causing the noise, but the relay contacts themselves have not been chattering.
Recently went through a warm spell for several days in SE CT so the stove was cold and we were on oil. No issues.
No issues with my shower Thurs morning at 0400 but wifey said hers was a bit chilly at 0600. She got home at 1715 to a house at 58 deg with high winds and a cold front moving in and said WTF? and lit the wood stove. I got home at 1900 and heard the bad news. Investigation reveals the oil boiler stone cold at 70 with the fire eye tripped. Reset fire eye and it took off ok, heated up ok, got above setpoint, then circulator started ok since the house was still at 64 but it continued to fire to over 200 when I shut it down.
Cycled the low limit setting. It clicks on and off.
Cycled the hi limit setting. It doesn't click on/off, so it seems like it's stuck on and allowing the boiler to overfire to a high temp.
Opened breaker, pulled knobs off aqua stat, removed 3 screws, removed cover, found white crusties, (evidence of slight water contamination from a slightly leaky DHW fitting) and a brown sticky substance (solder resin?). Cleaned this up with electrical contact cleaner. Looks brand new again. Re-assembled. Low limit seems to work ok. High limit seems way off, it still wanted to overfire to 200 deg. Shut it off for the night.
Turned it on and watched everything as she showered Fri morning. Low limit / diff seem to be working ok. Still not sure if high limit is AFU / reliable since the house is warm due to wood stove.
Question - Replace 28.5 year old Honeywell L 8124 A/C triple aqua stat with identical replacement? Maybe more reliable. Maybe longer lasting but looks like about $100 more.
What to use? Replace with newer digital/electronic version? Apparently, Honeywell is now going by Resedio. What's up with the name change? New ownership or what? Are they still any good?
What's better, old school electro-mechanical or new school digital/electronic. Probably got my $$$ worth out of a 28.5 yrs unit but what should I replace it with?
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