Space Heating and DHW combo: Is this efficient for DHW alone?
user-869687
| Posted in Mechanicals on
In a climate where the heating season is less than half the year, would a combination condensing boiler and indirect water heater (e.g. the Triangle Tube Prestige Excellence) still be efficient for supplying domestic hot water during the warmer months? Or does the efficiency of the DHW service depend on also using the boiler for for space heating?
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Replies
You are using the boiler when calling for DHW - it's the same burner supplying the heat.
An advantage of using the boiler in the off-season for DHW is that it stays clean rather than grow cobwebs.
But, unless you need the 30-110 thousand BTU output of the Excellence for heating and don't have a lot of simultaneous hot water use, you may be better off (and save money) with the TT Prestige Solo and an indirect DHW tank sized for your requirements. This will give you a DHW reserve and more hot water even with the smaller 16-60 thousand BTU unit.
Robert, thanks for your answer. My question should have read, "...also using the boiler for for space heating". Yes, that model may be overkill. The question is about the combo, because it's attractive to have fewer components. Sounds like you're in favor of the indirect DHW plus boiler combo for year-round use. This project will have in-floor hydronic heating, but the heating demand will be fairly light.