JBurdman7
New Member
Cheat sheet:
69 degree temp differential indoor / outdoor
1969 Hydrotherm cast iron boiler Model R-180 NG burner runs 26.66% of the time
All? The details…
I live in East central PA where we go a little below zero on the dozen coldest nights of a typical winter. Double digit below zero windchills are about as bad as it gets.
Home is post WWII wood frame, blown-in insulation, new windows, nearly all leaks sealed etc.
Boiler is a Hydrotherm installed Aug 1969. 180,000BTU in, 144,000BTU out
Gas valve, thermocouple, and tank thermostat independently failed / replaced 20-30 years ago.
I vaguely recall measuring the stack temp at 550F but I don’t recall for certain if the boiler was set to 180 F.
Pilot light, millivolt system, can gravity feed in a power failure.
I typically shut the pilot off in the summer.
I set the flow valve to be always open in order to have the gravity feed at hand. That valve is probably from 1946. The zone valve I leave electrically trigger. I have to open that in a power failure.
Sqft maybe 2,300, not sure
Radiation is finned wall registers. There are plenty. The burner would probably run continuous, or just about, if the tank temp were set high.
The basement is on its own zone but if that zone is allowed to trigger independently, we get leaks. The theory is the sudden expansion-flexes. So the basement zone is set to trickle when the upper floors call for heat. Never a leak doing that.
Thermostat stays at 71-72 F main floor. Basement trickle is adjusted to maintain 64+-. All radiation upstairs (small knee-wall rooms) is shut off and varies in temp, generally 60F and up, depending on ambient.
Until the temps start going below freezing I leave the boiler set at 160F. Once we start regularly going below freezing I go to 180. Then when spring gets closer, back to 160.
Flu is terra cotta lined, with the opening placed oddly low on the wall. We use a short NG tank DHW. Some 30 gallon shorts won’t even fit. 4 bedroom house but only 2 occupants so no worries. Might ding the resale value tho unless I get a tankless (next owners problem IMO.)
I don’t mean to bore you but you know how it is… if I err and no one catches it, we could chase the wrong rabbit.
Early in the morning Jan 21, 2019 ; 3F 12?MPH winds; I measured the boiler circulator on time with tank set to 180F as:
1:03AM turns on
7 minutes, I was upstairs, not sure if all was all burn time. I couldn’t hear
1:10 turns off
off for 17min 15 sec
Turns on 1:27:15AM
burner comes on ~45 sec later
1:33:30AM all shuts off
so a 5min 30 sec burn
after 17min 30 sec off
burns for 5min 45sec
All off, for 16 min
Ergo burner is on an average of 6 min (worst case) for every 16min 30 sec off
or 6/ 22.5 of the time = 26.66%; 26.66X 144,000BTU = 38,400BTU demand
I only water the system right before the heating season and if I hear any gurgle I’ll shut the heat off off, let it cool, and turn the water feed on again for a bit. I’d rather do that than risk coming home to a nasty leak. All has been well but the place is pushing 70yo.
Is that everything? My apologies if I forgot anything useful.
I have a sense of what improves efficiency but not much of an idea about what will kill the boiler quicker.
I know enough to know that I want to set the boiler temp back, as I do, that is about all. I never pushed that because I don’t know how far would be too far. I don’t care for making the circulator run a lot anyway.
I suspect that I should fashion a delay to make the circulator run longer, but I have no idea what temps to shoot for.
I suspect that a flu damper would help, but I doubt I have the height to install one, I also suspect that doing such modification for a 50yo plant would not be wise.
Is there anything I can do that would make the plant more efficient? I’m a tinkerer so the parts and labor would be near zero.
Also, any suggestions as to what plant this should be replaced with when it finally springs a leak? Not sure what a building inspector might think of seeing a 40,000BTU system tho.
All tips and comments appreciated! Thanks!
69 degree temp differential indoor / outdoor
1969 Hydrotherm cast iron boiler Model R-180 NG burner runs 26.66% of the time
All? The details…
I live in East central PA where we go a little below zero on the dozen coldest nights of a typical winter. Double digit below zero windchills are about as bad as it gets.
Home is post WWII wood frame, blown-in insulation, new windows, nearly all leaks sealed etc.
Boiler is a Hydrotherm installed Aug 1969. 180,000BTU in, 144,000BTU out
Gas valve, thermocouple, and tank thermostat independently failed / replaced 20-30 years ago.
I vaguely recall measuring the stack temp at 550F but I don’t recall for certain if the boiler was set to 180 F.
Pilot light, millivolt system, can gravity feed in a power failure.
I typically shut the pilot off in the summer.
I set the flow valve to be always open in order to have the gravity feed at hand. That valve is probably from 1946. The zone valve I leave electrically trigger. I have to open that in a power failure.
Sqft maybe 2,300, not sure
Radiation is finned wall registers. There are plenty. The burner would probably run continuous, or just about, if the tank temp were set high.
The basement is on its own zone but if that zone is allowed to trigger independently, we get leaks. The theory is the sudden expansion-flexes. So the basement zone is set to trickle when the upper floors call for heat. Never a leak doing that.
Thermostat stays at 71-72 F main floor. Basement trickle is adjusted to maintain 64+-. All radiation upstairs (small knee-wall rooms) is shut off and varies in temp, generally 60F and up, depending on ambient.
Until the temps start going below freezing I leave the boiler set at 160F. Once we start regularly going below freezing I go to 180. Then when spring gets closer, back to 160.
Flu is terra cotta lined, with the opening placed oddly low on the wall. We use a short NG tank DHW. Some 30 gallon shorts won’t even fit. 4 bedroom house but only 2 occupants so no worries. Might ding the resale value tho unless I get a tankless (next owners problem IMO.)
I don’t mean to bore you but you know how it is… if I err and no one catches it, we could chase the wrong rabbit.
Early in the morning Jan 21, 2019 ; 3F 12?MPH winds; I measured the boiler circulator on time with tank set to 180F as:
1:03AM turns on
7 minutes, I was upstairs, not sure if all was all burn time. I couldn’t hear
1:10 turns off
off for 17min 15 sec
Turns on 1:27:15AM
burner comes on ~45 sec later
1:33:30AM all shuts off
so a 5min 30 sec burn
after 17min 30 sec off
burns for 5min 45sec
All off, for 16 min
Ergo burner is on an average of 6 min (worst case) for every 16min 30 sec off
or 6/ 22.5 of the time = 26.66%; 26.66X 144,000BTU = 38,400BTU demand
I only water the system right before the heating season and if I hear any gurgle I’ll shut the heat off off, let it cool, and turn the water feed on again for a bit. I’d rather do that than risk coming home to a nasty leak. All has been well but the place is pushing 70yo.
Is that everything? My apologies if I forgot anything useful.
I have a sense of what improves efficiency but not much of an idea about what will kill the boiler quicker.
I know enough to know that I want to set the boiler temp back, as I do, that is about all. I never pushed that because I don’t know how far would be too far. I don’t care for making the circulator run a lot anyway.
I suspect that I should fashion a delay to make the circulator run longer, but I have no idea what temps to shoot for.
I suspect that a flu damper would help, but I doubt I have the height to install one, I also suspect that doing such modification for a 50yo plant would not be wise.
Is there anything I can do that would make the plant more efficient? I’m a tinkerer so the parts and labor would be near zero.
Also, any suggestions as to what plant this should be replaced with when it finally springs a leak? Not sure what a building inspector might think of seeing a 40,000BTU system tho.
All tips and comments appreciated! Thanks!