HW Elec or LP?

[MainelyUS]

We are finally on our first extended trip in the Windjammer...hookup completed we set the HW heater to electric following the instructions in the Suburban manual, flipped on the Water Heater switch and within the short period of time we had hot water. We than turn on the LP for the Heater (only 5 degrees difference btw refer temp and outside temp this morning ) and discover that our HW heater had switched to LP even with the elec switch on. Question is: is this normal or should the HW heater have stayed in Elec mode with the LP turned on for the main cabin heater & stove?
Looking forward to your insights....

Happy Trails

[wmtire]

Originally Posted by MainelyUS

We are finally on our first extended trip in the Windjammer...hookup completed we set the HW heater to electric following the instructions in the Suburban manual, flipped on the Water Heater switch and within the short period of time we had hot water. We than turn on the LP for the Heater (only 5 degrees difference btw refer temp and outside temp this morning ) and discover that our HW heater had switched to LP even with the elec switch on. Question is: is this normal or should the HW heater have stayed in Elec mode with the LP turned on for the main cabin heater & stove?
Looking forward to your insights....

Happy Trails

A little confused here, but think I may understand. When you say you turned on the LP for the Heater....do you mean the furnace, and not the water heater?

The Suburban water heater can have two different modes of being able to heat water. One is by propane and the other is by electric heating element. These two modes operate independently of each other. each one has it's own switch to turn it on and off. They also both have their own thermostats that allow either the propane to fire up or the heating element to turn on, depending on the water temp.

You can turn on the propane, even with the electric heating element on. If the water is not at the temp that the thermostats are set for, then the propane will come on too (if the switch for it is turned on) and both will heat the water simultaneously until the water gets to temp. You usually use both when taking showers in succession or need heated water quicker, since the propane side does heat water faster than just the electric.

[wmtire]

This FAQ may also help, in making sure you are using the right switches, etc. Nothing flips to LP, as you have to manually turn on the switch for it, as well as manually turn on another switch for electric heating element. Sound like maybe you had the propane/dsi switch on, but it wasn't working until you actually opened up the propane cylinders and perhaps turned it off/on again.

http://www.forestriverforums.com/for...ore-36197.html

[Kenny kustom]

Maybe you turned on lp to wh?

Show us your switches!


2008 F350 CCSB V10
2016 Sabre 36QBOK

[DaveSchwartz]

Assume you have the Suburban SW6DE like most of us...

The WH didn't really 'switch modes'. If you enable both the gas and electric, once the temperature falls below either thermostat's set point (they are independent and 130F, give or take, for Suburban) each will independently call for heat. If the normal variability of the non-adjustable thermostat for the 12V side calls for heat before the 120V side, you will probably never end up using electric. Even if the 120V side is below the 12V side, you will probably only end up using the electric to maintain temperature against standby losses - once you start using hot water, the temp will probably fall below both and the gas, being more powerful, will end up being the one that brings it up to the setpoint.

If the AC element is enabled, you would only enable the gas to provide faster recovery. If you don't have situations where you run out of hot water, leave the propane off.

[MainelyUS]

Thanks for the replies....
wmtireI should have used furnace and not heater that might have helped. I did turn on both switches, elec switch located on the HW heater and the Water Heater switch in the main cabin (see pics)
assuming you needed the main HW switch on when using the HW heater.
If I understood everyones comments correctly all I need to do is to turned on the elec switch located on the HW heater and not the Water Heater switch on the main switch panel if I only want to run on elec. I understand the reasons to have both on.

Would be helpful if this info was included in the operation manual....but then again we won't have this FORUM.

Thanks for the quick response.

Happy Trails

[wmtire]

Originally Posted by MainelyUS

Thanks for the replies....
wmtireI should have used furnace and not heater that might have helped. I did turn on both switches, elec switch located on the HW heater and the Water Heater switch in the main cabin (see pics)Attachment 89826
Attachment 89827 assuming you needed the main HW switch on when using the HW heater.
If I understood your comments correctly all I need to do is to turned on the elec switch located on the HW heater and not the Water Heater switch on the main switch panel if I only want to run on elec. I understand the reasons to have both on.

Would be helpful if this info was included in the operation manual....but then again we won't have this FORUM.

Thanks for the quick response.

Happy Trails

You are correct. The switch inside your RV is ONLY to the propane/dsi side of your water heater. This is the switch you use to turn on the Direct Spark Ignitor for your propane. Only use it when you are wanting to use the propane part of your water heater.

The switch, accessed from outside your RV, on the front of the water heater is ONLY to the electric heating element.

If you only want to use the electric heating element, then you turn on the outside switch (make sure there is always water in the heater though beforehand). You will leave the switch inside your RV, in the OFF position.

Don't feel bad, this is one of the most misunderstood things, and is very ill-explained by many RV dealers when purchasing a RV. This is why we have the detailed FAQ I linked you to here in the forum. Hope it helped.

So, if I am correct in my initial assumption..you did have the inside DSI switch on, but the water heater wasn't using propane because the propane tanks were off. Here is another tidbit. Since the propane tanks were off, the DSI wouldn't have been able to ignite the propane (cause there wasn't any). This is also what shows up as a fault in the system. If you will look at the pic you posted of the inside switch, you should also see the little red light beside it that says DSI Fault. This light should have been on the whole time that the switch was on, yet the propane wasn't. it's an indicator for you. Also this light will come on when you first turn on the switch, until the DSI ignites the propane, which can take a few seconds, usually 15-30. After the propane ignites, the red fault light goes off. If it doesn't then the propane isn't lighting and you need to check and find out why.

This is also explained in the FAQ link.