So having decided to go cast iron rather than deal with the various mod-con issues, I have received the following proposal from a very competent installer. I have to choose between the Peerless MI85-03, Buderus GC144-3 and Burnham ES23. I am leaning towards the Peerless not only because of its extra-thick cast iron construction, reputation, parts availability and because the 60Kbtu firing rate, 51K btu DOE and 44Kbtu net IBR is closest in line with my 38Kbtu heat loss, which is likely actually a bit lower than that. Trying to keep the system simple.
I’m glad to receive your opinions on this. (See attached rough diagram.)
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Existing System info:
Lower Hudson Valley, NY, 1924 Colonial, 3-zone gravity converted system into series ¾” copper.
Main and 2nd Floor, cast iron rads more than sufficient EDR; basement baseboard less than sufficient EDR.
6” spray foam insulation under roof rafters; 4 inch spray foam gable walls; 4 inch dense pack cellulose in house walls.
House Loss @Design Temp: 38,640. Total Existing House Gain @Design Temp: 34,480btu .
Lowest loss Zone 2 @50ºF 1349BTUs.
68º indoor set temp; design temp 10degrees. Supply-return ∆T 20º;
Current boiler is 1981 WM 210Kbtu, de-rated to fire at 170Kbtu. Most cycles less than five minutes. HWH by direct 30kbtu 50 gallon HWH.
System water is hard and fairly high in chlorides.
Proposal
(Work done by others is not included in the estimate: Installation of a chimney liner.)
• Cut out and remove the existing hot water boiler, hot water heater and all the existing near boiler piping.
• Pour a new 4" depth x 24" wide x 24" length concrete pad for the Burnham ES23.
Install either a Burnham ES23, Peerless MI85-03 SPARK-WPC-N or the Buderus GC144-3 cast iron
hot water boiler with near boiler piping and controls containing:
• Isolation drain and purge valves.
• Air and dirt magnet separators.
• High efficient ECM Delta T VT2218 circulating pump with isolation pump flanges.
• High efficient ECM circulating pump with isolation pump flanges. _________
• 3- Low Energy draw zone valves.
• 3- Quicksetter flow control valves.
• Hydronic expansion tank with support bracket.
• Back flow preventer and auto regulator combo unit.
• Inline sediment and De-mineralized filters.
• Zone Control Box.
• Outdoor Reset Control.
Pipe the Flue pipe into the chimney.
Install a Turbomax 23 Reverse Indirect Tank.
• Cold and Hot water potable water side:
• Isolation valves.
• Thermostatic mixing valve
• Thermal expansion tank with support bracket.
• Set up with DHW priority with 30min max before returning to heat call.
(It will be piped primary/secondary via the Turbomax working as a buffer tank. The water temps will be set at a minimum of 160 on the supply side. DHW yield ––given mixdown to 120––will be 88 gallons for the 1st hour and 75 gallons continuous flow.
• Run an 18-gauge wire from the boiler to the north side of the house to install the outdoor sensor.
• Pipe the 3/4" cold and hot water lines from the existing location of the old water heater to the new location of the new Turbomax Reverse Indirect Tank.
• Install a Field Control CAS- 4 Fan In A Can Combustion In Take Unit.
• Pipe 4"x 10' 18 gauge galvanized pipe from the fan in a can to the ouside of the house with a termination hood.
• Wire the Fan In A Can with boiler.
• Fill the heating system with water and system cleaner.
• Power flush the system with Fernox F5 and remove any debris that is in the radiators and baseboard.
• Re-fill the heating system with de-mineralized water and Fernox F1 conditioner/inhibitor and power purge the air out of the entire heating system (radiator, baseboard).
• Perform a combustion analysis and make any adjustment if needed to insure the boiler is within the manufacturers combustion numbers.
Questions, Issues:
• I regret that we can’t get supply temp down to 150, but contractor wants to ensure return temps don’t get below 130. Were this a modcon and with our fairly well insulated house we’d be looking at 140º supply temps on a design day of 10ºF. Contractor says to get the lower temps it would have to piped like an injection setup but still the boiler water would have to be at a minimum of 160. Obviously ODR is kind of limited here. We could add an ODR mixing device to get heating supply temp down.
• Concern about Taco ECM VT-2218 overpumping. By estimated head loss method, I measure 12ft head @4gpm for the longest Zone 2; by actual calculated method based on the 1gpm required, head loss for Zone 2 is .711ft of head. Perhaps all this falls within a general range and should not be a concern. Current circs with oversized boiler are Grundfos 3-speed Brute for Basement Zone and Zone 2—both on slowest setting––and Taco 007 for Zone 1.
I’m glad to receive your opinions on this. (See attached rough diagram.)
Existing System info:
Lower Hudson Valley, NY, 1924 Colonial, 3-zone gravity converted system into series ¾” copper.
Main and 2nd Floor, cast iron rads more than sufficient EDR; basement baseboard less than sufficient EDR.
6” spray foam insulation under roof rafters; 4 inch spray foam gable walls; 4 inch dense pack cellulose in house walls.
House Loss @Design Temp: 38,640. Total Existing House Gain @Design Temp: 34,480btu .
Lowest loss Zone 2 @50ºF 1349BTUs.
68º indoor set temp; design temp 10degrees. Supply-return ∆T 20º;
Current boiler is 1981 WM 210Kbtu, de-rated to fire at 170Kbtu. Most cycles less than five minutes. HWH by direct 30kbtu 50 gallon HWH.
System water is hard and fairly high in chlorides.
Proposal
(Work done by others is not included in the estimate: Installation of a chimney liner.)
• Cut out and remove the existing hot water boiler, hot water heater and all the existing near boiler piping.
• Pour a new 4" depth x 24" wide x 24" length concrete pad for the Burnham ES23.
Install either a Burnham ES23, Peerless MI85-03 SPARK-WPC-N or the Buderus GC144-3 cast iron
hot water boiler with near boiler piping and controls containing:
• Isolation drain and purge valves.
• Air and dirt magnet separators.
• High efficient ECM Delta T VT2218 circulating pump with isolation pump flanges.
• High efficient ECM circulating pump with isolation pump flanges. _________
• 3- Low Energy draw zone valves.
• 3- Quicksetter flow control valves.
• Hydronic expansion tank with support bracket.
• Back flow preventer and auto regulator combo unit.
• Inline sediment and De-mineralized filters.
• Zone Control Box.
• Outdoor Reset Control.
Pipe the Flue pipe into the chimney.
Install a Turbomax 23 Reverse Indirect Tank.
• Cold and Hot water potable water side:
• Isolation valves.
• Thermostatic mixing valve
• Thermal expansion tank with support bracket.
• Set up with DHW priority with 30min max before returning to heat call.
(It will be piped primary/secondary via the Turbomax working as a buffer tank. The water temps will be set at a minimum of 160 on the supply side. DHW yield ––given mixdown to 120––will be 88 gallons for the 1st hour and 75 gallons continuous flow.
• Run an 18-gauge wire from the boiler to the north side of the house to install the outdoor sensor.
• Pipe the 3/4" cold and hot water lines from the existing location of the old water heater to the new location of the new Turbomax Reverse Indirect Tank.
• Install a Field Control CAS- 4 Fan In A Can Combustion In Take Unit.
• Pipe 4"x 10' 18 gauge galvanized pipe from the fan in a can to the ouside of the house with a termination hood.
• Wire the Fan In A Can with boiler.
• Fill the heating system with water and system cleaner.
• Power flush the system with Fernox F5 and remove any debris that is in the radiators and baseboard.
• Re-fill the heating system with de-mineralized water and Fernox F1 conditioner/inhibitor and power purge the air out of the entire heating system (radiator, baseboard).
• Perform a combustion analysis and make any adjustment if needed to insure the boiler is within the manufacturers combustion numbers.
Questions, Issues:
• I regret that we can’t get supply temp down to 150, but contractor wants to ensure return temps don’t get below 130. Were this a modcon and with our fairly well insulated house we’d be looking at 140º supply temps on a design day of 10ºF. Contractor says to get the lower temps it would have to piped like an injection setup but still the boiler water would have to be at a minimum of 160. Obviously ODR is kind of limited here. We could add an ODR mixing device to get heating supply temp down.
• Concern about Taco ECM VT-2218 overpumping. By estimated head loss method, I measure 12ft head @4gpm for the longest Zone 2; by actual calculated method based on the 1gpm required, head loss for Zone 2 is .711ft of head. Perhaps all this falls within a general range and should not be a concern. Current circs with oversized boiler are Grundfos 3-speed Brute for Basement Zone and Zone 2—both on slowest setting––and Taco 007 for Zone 1.