Which switch is which?

Thanks Mont. The switchpanel for the tank heaters is amidships. And yes my dump valves are similarly located in the insulated underbelly.

I have a 2005 Fleetwood Pride 5th wheel with the arctic package. like yours, I have two switches, but mine is located in the front storage compartment. I only have one gray tank and the position of the switches may or may not be the same as yours.

I agree with Gordon in a previous reply to your question, that checking the amperage of each switch would be the easiest way to determine the switch for the two gray tanks. If your dump valves are like mine, they are located in the insulated underbelly and kept warm by the furnace duct.

That is a good idea Gordon! I don't know which tank has what, but assuming each tank draws relatively the same amperage, that would determine which switch serviced two tanks and which only serviced one. The next problem . . does one feed the aft galley tank and the other go forward to the black and bathroom grey tank? If I only want to heat the black tank and used that logic, I would end up leaving the heat on an empty tank (the aft galley tank) and nothing on the black tank.

Perhaps someone reading this post actually worked at the factory at or around the time these units were made, and can give me some insights. Meanwhile, I leave both waste tank switches OFF and wait (and hope) until such time as something freezes. (So far so good - the full black tank drained freely today, and it's -8 C or about 18 F.) Now that is has turned cold and is likely to stay that way, I guess I will find out one way or another if I need to heat everything. Then I will just turn both switches on and operate with a level in the grey tanks at all times.

My neighbor lives full time in a trailer without the 'arctic package' and, by virtue of skirting and maintaining heat in the trailer at all times, seems not to have any trouble.

If you know tank x has two pads and tank y has only one, a clamp on ammeter will tell you which. Clamp on either at the switch itself or the output of the converter. When on, whichever draws more current is your double mat tank.

Thanks Lyle. That would make sense to me, based on what is visible above and below. With only two 'waste tank heat' switches, and three waste tanks, my instincts tell me one is for the (empty) grey tanks and one is for the black tank. But my experience with this (or any) unit is less than one year, hence my query to this forum. Thanks again to all for your suggestions.

Thirdwish, from what I've seen/read, "heated" valves tend to go along with a "heated underbelly", i.e. they're heated by forced air from the furnace. If the actual valve body is enclosed in the underbelly, this is likely the case.

Lyle

Could be rigs were wired differently, maybe the winter package install was subcontracted and each sub had their own way of doing it?

No, the galley panel has no switch for waste tank heating. Other than tank level indicators (and only the fresh water tank level indicator works) there are only switches for the hot water tank (on/off for propane and hydro), ceiling fan, overhead light and water pump.

newman fulltimer wrote:

GordonThree wrote:

newman fulltimer wrote:
waste tank has 2 mats one on tank one on valve area thats why 2 waste tank switches

What about the other tank?

he should have another switch in the kitchen for the galley tank

Thirdwish have you found this switch in the galley?

Thank you all for the replies everyone.

Azdryheat - the previous owner did not have the info, and did not use the unit during the winter, so just winterized everything and never used the tank heaters. And I think he picked it up on a repo, so nothing from original owner.

Newman - do you mean that the BLACK waste tank has two mats - one in tank and one on valve? I never considered the possibility that there are no heaters in the grey tanks, and two in the black tanks. But if I knew that was the case, I would just turn both switches on. There is nothing in the galley that operates tank heaters unless it is something I have yet to stumble across...

Farmboy and Garden3, we have skirted the trailer and before I did that I wrapped all the lines with bubble-wrap insulation (and tracing on the main header outside the skirting) from the black tank drain valve to the sewer.

Still holding out in case someone else with the same unit (they had to have built quite a few, we like it a lot) can come up with the answer.

Cheers!