Both space and water heating are almost always better served with a condensing boiler and indirect water heater. In used combi water heater/boilers one has to know the loads and the design temperatures of those load terminals. Be sure your boiler/water heater is capable of producing water hot enough for a high temperature emitter such as fin tube baseboard. As for piping. One should know before putting in the order, how any gas-fired appliance is going to be piped. The installation manual should be on line. Finally, there is the regular maintenance and support.
Professionals normally buy products from local distributors with direct or nearly direct access to the manufacturer. The distributor has hundreds of professional customers and a vast experience with the appliances he sells. Issues can be taken care of quickly. Before you jump in, perhaps a few phone calls to local contractors that service the Rinnai combi you are looking at and another to a local distributor for available parts...say a flow switch.
Just thinking... |