What Does That Switch Do?

So many switches. You probably have a few hanging around your coach that you haven’t fully explored yet. Like us. Three years into our current coach and I am still learning about the various systems. Today we will take a look at some switches found on the Oasis Remote Operating Panel.

In our coach, this is what that panel looks like.

Looks like Oasis elected to remove one of the switches and they were too cheap to run a different plate. We can safely ignore the ENGINE PRE-HEAT switch. We don’t have that one.

But we do have two other switches: BURNER and AC HEAT.

The BURNER switch is a simple off-on toggle switch. The AC HEAT switch is a three-way toggle switch.

Here is what the Oasis manual has to say about these particular switches:

Activating the Burner (Primary) and AC Heat (Secondary) from the Remote Operating Panel

Activating the Burner (Primary Heat Source)

The burner switch on the Remote Operating Panel controls the ON/OFF of the diesel burner (primary heat source). When the burner switch is turned ON, the diesel portion of the OASIS Heating Module will turn ON after ten seconds. The Burner LED will turn ON when the diesel burner has been activated. The burner will continue to operate until the coolant in the OASIS Heating Module reaches the set operating temperature range. At this point, the diesel burner will turn OFF. If the OASIS Heating Module coolant should cool down below this temperature range, the burner will again commence firing and will continue until either the burner switch on the remote panel is turned OFF or the temperature range is again achieved. If the burner switch on the remote panel is turned OFF, the burner stops and the OASIS Heating Module enters a two minute cool down stage prior to completely shutting down.

Activating the AC Immersion Element(s) (Secondary Heat Source)

Place the AC power switch on the Remote Operating Panel to either the one element or the two element position. The AC Heat (green) LED will turn ON indicating the AC element(s) are energized and the coolant is being electrically heated. They will continue to operate until the coolant in the OASIS Heating Module reaches the set operating temperature range. At this point, the elements will turn OFF. If the OASIS Heating Module coolant should cool down below this temperature range, the AC elements will again be energized and will continue until either the AC switch on the remote panel is placed in the OFF position or the temperature range is again achieved. If the AC element switch on the remote panel is turned OFF, the AC elements are de-energized and the AC Heat (green) LED turns OFF.

Activating the Burner and AC immersion Element(s) Jointly

Turn the burner switch ON and place the AC power switch on the Remote Operating Panel to either the one element or the two element position. The Burner and AC Heat (green) LED’s will turn ON indicating the diesel burner and AC element(s) have been selected.

Oh, and one other pointer a bit later in their documentation:

Activating the Domestic Hot Water

As long as heat is available in the OASIS Heating Module, the Distribution Module will respond to a call for domestic hot water. Ensure that a heat source has been selected (i.e. Burner, AC, Engine). The production of the domestic hot water is continuous on the Burner operation and limited when using AC or Engine.

All clear?

It took me a bit of research to understand when you might use the BURNER versus the AC HEAT and, for that matter, when you would use both.

Here then is how we use these particular switches.

If we are connected to a 50 amp service in cold weather and we want to heat the coach using the Hydronic heat system then turning the BURNER switch ON and turning AC I & AC II switch ON is our best option. Diesel fuel packs a lot more punch over electricity in terms of making heat. The AC I & AC II will reduce the draw on diesel fuel.

If we are connected to a 50 amp service in a mild to warmer climate, then turning the BURNER switch OFF and using AC I & AC II is usually our best option. Sufficient to keep the domestic hot water hot for light duties (e.g., washing hands, doing dishes). When we want to ensure continuous hot water, say for a long shower, we can turn the BURNER switch ON a few minutes before the shower and turn it off after the shower is finished. Keeping the BURNER switch OFF means less noise for our neighbours. Whenever the BURNER switch is left ON the diesel burner will periodically run. It is surprisingly loud. Especially at night.

If we are connected to a 30 amp service then turning the BURNER switch ON and using AC I is usually our best option.

If we are paying for electricity then we have to calculate the tradeoff between burning diesel fuel for heat against the cost of using electricity. In warmer climates we are likely ahead to use electricity over diesel.