water heater question

[rjbny]

My brother is boondocking with our 19 this week and he replaced the defective control module. At first he couldn't get the water heater going even after replacing the module. He then turned the outside switch on and the water heater started working. This was puzzling to me because the water heater worked on propane for the first few days before the control module died and the outside switch was clearly OFF.

The Suburban manual for the water heater is pretty pathetic, but my understanding was that the outside switch is OFF unless you are running on electric.

Although it is great to finally have hot water again, can someone on the forum clarify whether the outside switch should be ON or OFF when we want to run on propane while boondocking?

[rbryan4]

Originally Posted by rjbny

...can someone on the forum clarify whether the outside switch should be ON or OFF when we want to run on propane while boondocking?

Propane operation is independent of the outside switch. It runs on propane from the inside switch. Is it running on propane now or on electric only?

[rjbny]

Originally Posted by rbryan4

Propane operation is independent of the outside switch. It runs on propane from the inside switch. Is it running on propane now or on electric only?

Thanks, that is helpful.

The context for this today is that we ran completely on solar for about 3 weeks but had to move to a shadier campsite and it didn't keep up. Before we could get a generator in place the batteries depleted pretty far. Now, we're trying to get the batteries back up to a healthy level during the limited generator hours. I didn't want the water heater to consume the electricity from the generator, so wondered what impact the switch would have on that.

My brother just texted and said he had to turn off the EMS to get the generator to start charging. Does that sound right?

[rbryan4]

Originally Posted by rjbny

I didn't want the water heater to consume the electricity from the generator, so wondered what impact the switch would have on that.

If you're camping in shade (reduced solar output) with no hookups, and you want to reduce battery consumption, turn the electric switch off on the water heater. Use propane only. But it sounds like since the control module was replaced, you aren't able to do that?

Originally Posted by rjbny

My brother just texted and said he had to turn off the EMS to get the generator to start charging. Does that sound right?

If you want to run a generator with the EMS on, you'll need to use a plug on the unused receptacle of the generator that bonds the open neutral. Otherwise, turn the EMS off.

http://www.dyersonline.com/progressi...ator-plug.html

[Brian B-P]

Originally Posted by rjbny

Now, we're trying to get the batteries back up to a healthy level during the limited generator hours. I didn't want the water heater to consume the electricity from the generator, so wondered what impact the switch would have on that.

It sounds like it's heating on electricity, because the outside switch is turned on and the generator is providing power (which of course is not what you want to do).

[Brian B-P]

Originally Posted by rbryan4

If you're camping in shade (reduced solar output) with no hookups, and you want to reduce battery consumption, turn the electric switch off on the water heater. Use propane only.

You mean reducing power consumption (from the generator), right? The electric element of the water heater will never use battery power.

[rbryan4]

Originally Posted by Brian B-P

You mean reducing power consumption (from the generator), right? The electric element of the water heater will never use battery power.

So it's AC only? I wasn't aware of that, since my water heater is propane only, and I've never used the two-way. Makes sense.

In that case, I'd still turn it off, if the objective is to maximize battery charging via a generator.

[Brian B-P]

Originally Posted by rbryan4

So it's AC only? I wasn't aware of that, since my water heater is propane only, and I've never used the two-way. Makes sense.

Yep, it's a 120 V AC element, and in an Escape with an inverter and transfer switch it is sensibly wired... meaning that the water heater circuit is not supplied by the transfer switch, so it can't run on battery+inverter power.

Originally Posted by rbryan4

In that case, I'd still turn it off, if the objective is to maximize battery charging via a generator.

I would at least turn it off to minimize generator noise and fuel consumption. Many generators can run the converter/charger at full output (700 watts?) and the water heater element (about 1400 watts) at the same time, but if using a little 1000-watt generator or needing absolutely full charging output with a 2000-watt generator, running the water heater element wouldn't be viable.

[rjbny]

Originally Posted by rbryan4

If you're camping in shade (reduced solar output) with no hookups, and you want to reduce battery consumption, turn the electric switch off on the water heater. Use propane only. But it sounds like since the control module was replaced, you aren't able to do that?



If you want to run a generator with the EMS on, you'll need to use a plug on the unused receptacle of the generator that bonds the open neutral. Otherwise, turn the EMS off.

Progressive Industries Generator Plug - Generator Accessories - Generators - Electrical

Lots of great information here. Thanks for the education!

To summarize:

1. In order to use a generator to charge the batteries, you either need to turn the EMS OFF or bond the open neutral at the generator in some way.

2. In order to maximize the amount of juice going into the batteries when charging with a generator, the external switch for AC on the hot water tank should be OFF so that propane is used.

Please correct me if I've misunderstood.

[rbryan4]

First point, yes. To use the EMS with a generator, you need to bond the open neutral. The practical way to do that is with a Progressive Industries Gen Plug.

On the second point, as Brian pointed out, that depends on the size of the generator, but generally, if the generator is a small one, then yes.