The new thermostat, even if it is an older analog model, could improve the performance of your boat’s furnace. We were having excessive trouble with our Webasto D90 furnace for years. We would be lucky to get a full season without problems. Finally, during a service call and after many, many problems, the thermostat was replaced. Lo and behold, the furnace has been working for almost two years (time for service in any case).

So, a new thermostat could actually help with problems. I never thought a thermostat could have much to do with the furnace’s operation. After all, isn’t it just an on/off switch? Then, I discovered there are actually three wires going to the thermostat, so it’s not a simple on/off switch. One other feature of the digital thermostat is that it accurately displays the current temperature on the thermostat.

The convenience is great. We now have a digital thermostat that has two temperature settings. The graphic on the thermostat is a moon or a sun. It is simple and easy to use once it’s set. I have the moon’s low setting at 49 degrees (lower than the old mechanical thermostat’s available setting). The second setting (sun) is at about 69 degrees. Then, if the boat gets too warm, we just press the moon button and off it goes. It is easy to increase/decrease one or the other temperature on the fly.

Of course, check with your furnace manufacturer and get only a thermostat compatible with your brand of furnace. But if your experience is like ours, you will love it: low cost and great results.