Good Morning all...first post here and hope I can get some help from the experts...apologies up front for long winded post....
Background....3400 sq ft house, heat loss of 85000BTU, heating is all in floor radiant, both stories, pex in gypcrete slabs. Heating source is a Benjamin cc500 wood/oil combo unit, pressurized. System is 5 years old.
The system works very well on oil but sucks it back huge....approximately 1200 gallons year....however we do not use the oil unless really cold, only use the wood as we have 40 acres and a lifelong supply of wood. The benjamin is not designed and cannot keep up with heat load using just wood as it cannot get hot enough. We have managed for 5 years, but the fire has to be stocked every 2 to 3 hours and ashes removed every 2 to 3 days...a pain. The boiler is currently in our attached garage in a mechanical room.
Several neighbors have switched to OWB recently and love them so this year we invested in the Central boiler 6048, (397 gallons), we run 100' thermopex to the mechanical room. We put a sidearm HX on the hot water tank, (40Gallon), and then used a sheel and tube HX to tie in to the pressurized system. The HX is rated to 150,000 btu which is a little more than the oil output on the benjamin which is 125,000.
The central boiler unit is terrific...in -15 C weather we are filling twice per day....and it is putting 175 degree water into our mechanical room. Hot water is excellent, but we are not satisfied with the HX which ties into the existing pressurized system and radiant floors. In the past using the benjamin on oil....our supply lines to the radiant ran at 110 to 120 degrees....with the new system we cannot seem to get much over 100 degrees....(we had hoped that having a supply temp of 150 degrees minimum from the new central boiler we would just have to temper with cooler water). It appears that the return loops from our radiant system into the HX are cooling it down so that the supply temp is not getting as high as we hoped.
Ok questions:
1. Can we depressurize the Benjamin boiler, eliminate the shell and tube HX, and just tie new supply from the central boiler into our radiant floor system?
2. How difficult is it to depressurize and what are the pros and cons....?
3. Would we still be able to use the Benjamin boiler as our back up with the oil burner?
4. Would we be better to just sell the benjamin unit, tie into the radiant floor with the new boiler and go to electric baseboard etc...for back up?
We must have some form of back up heat for when we go away....
Thanks in advance for any advice
Mike
Background....3400 sq ft house, heat loss of 85000BTU, heating is all in floor radiant, both stories, pex in gypcrete slabs. Heating source is a Benjamin cc500 wood/oil combo unit, pressurized. System is 5 years old.
The system works very well on oil but sucks it back huge....approximately 1200 gallons year....however we do not use the oil unless really cold, only use the wood as we have 40 acres and a lifelong supply of wood. The benjamin is not designed and cannot keep up with heat load using just wood as it cannot get hot enough. We have managed for 5 years, but the fire has to be stocked every 2 to 3 hours and ashes removed every 2 to 3 days...a pain. The boiler is currently in our attached garage in a mechanical room.
Several neighbors have switched to OWB recently and love them so this year we invested in the Central boiler 6048, (397 gallons), we run 100' thermopex to the mechanical room. We put a sidearm HX on the hot water tank, (40Gallon), and then used a sheel and tube HX to tie in to the pressurized system. The HX is rated to 150,000 btu which is a little more than the oil output on the benjamin which is 125,000.
The central boiler unit is terrific...in -15 C weather we are filling twice per day....and it is putting 175 degree water into our mechanical room. Hot water is excellent, but we are not satisfied with the HX which ties into the existing pressurized system and radiant floors. In the past using the benjamin on oil....our supply lines to the radiant ran at 110 to 120 degrees....with the new system we cannot seem to get much over 100 degrees....(we had hoped that having a supply temp of 150 degrees minimum from the new central boiler we would just have to temper with cooler water). It appears that the return loops from our radiant system into the HX are cooling it down so that the supply temp is not getting as high as we hoped.
Ok questions:
1. Can we depressurize the Benjamin boiler, eliminate the shell and tube HX, and just tie new supply from the central boiler into our radiant floor system?
2. How difficult is it to depressurize and what are the pros and cons....?
3. Would we still be able to use the Benjamin boiler as our back up with the oil burner?
4. Would we be better to just sell the benjamin unit, tie into the radiant floor with the new boiler and go to electric baseboard etc...for back up?
We must have some form of back up heat for when we go away....
Thanks in advance for any advice
Mike