Posted by Harold Kestenholz - Hydronic Network on August 02, 2001 at 06:44:08:
In Reply to: Need advice on Laars Endurance gas boiler(formerly Trianco Heatmaker) posted by Paul from NH on August 01, 2001 at 22:58:09:
The boiler heat circuit holds 3 gallons of water, but the unit holds 20 gallons of water for the domestic hot water, so the heat stored is about what a small cast-iron boiler would hold.
The boiler must be installed according to factory recommendation. This means that the boiler is not to be vented into an unlined brick chimney as it will run condensed water from the combustion gases down the chimney and wreck the chimney. The stainless flue might be extended through the chimney and the water collected from the bottom, but it is less expensive just to direct vent it as directed.
Part of its cost is the modulating controls, the stainless chamber and the appliance-like appearance. The modulating controls make it more difficult to make the unit inefficient through oversizing. The copper heat exchangers are a design used for many decades.
The major concern is to have the water flow through the unit properly. This takes a careful water radiation circuit designer who follows established desigh procedures.