Water heater - Ready?

[Yoshimura]

Beside opening the faucet, how do you determine that the water in your water heater tank if fully warmed?

[hbn7hj]

That is easy. Slip the probe of this thing behind the tank insulation.

https://www.amazon.com/General-Tools.../dp/B00M9T7ZF8

To take a shower turn the water heater off when the temperature reaches 103F or whatever works for you and use the hot water only.
Harry

[Bud]

Originally Posted by hbn7hj

That is easy. Slip the probe of this thing behind the tank insulation.

https://www.amazon.com/General-Tools.../dp/B00M9T7ZF8

To take a shower turn the water heater off when the temperature reaches 103F or whatever works for you and use the hot water only.
Harry

And this is left in place for shower after shower?

Bud

[markopolo]

A temperature probe also helps if you're trying to conserve propane usage. You can turn the heater off when the temperature you require is reached.

With Suburban water heaters I find that it is easy to hear the roar of the burner flame and also hear when it stops. The water is hot when the roar stops.

[hbn7hj]

Originally Posted by Bud

And this is left in place for shower after shower?

Bud

Yep, permanent install. Saves a lot of propane and water.

[Bud]

Originally Posted by hbn7hj

Yep, permanent install. Saves a lot of propane and water.

Thanks for getting me off my ........... thought about it for years. Done.
Ordered some, 2 in a pack with good reviews.

Bud

[Yoshimura]

Thanks for the suggestions.

After checking the wiring diagram, I now think wiring a LED to the Gaz Valve signal (BR wire)...

[GeorgeRa]

Originally Posted by Yoshimura

Thanks for the suggestions.

After checking the wiring diagram, I now think wiring a LED to the Gaz Valve signal (BR wire)...

Just wonder why do you need to know if water is hot besides seeing the water heater switch being on and roar of the water heater stopped.

[Yoshimura]

Originally Posted by GeorgeRa

Just wonder why do you need to know if water is hot besides seeing the water heater switch being on and roar of the water heater stopped.

We need to know so we can take a shower as soon as possible after we arrive at a site. Maybe listening to the roar could work but a more convenient way would be appreciated.

[avanti]

Originally Posted by Yoshimura

We need to know so we can take a shower as soon as possible after we arrive at a site. Maybe listening to the roar could work but a more convenient way would be appreciated.

Your LED mod should work.

Note, though, that unless you are a member of the Church of No Propane While Driving, there is no reason why you can't have hot water as soon as you pull into camp.

[GeorgeRa]

Your RV is new so I don’t know how much experience you have with RV water heaters. They tend to be well insulated and keep shower temperature for even 24 hrs. with burner off.

[Yoshimura]

Originally Posted by avanti

Your LED mod should work.

Note, though, that unless you are a member of the Church of No Propane While Driving, there is no reason why you can't have hot water as soon as you pull into camp.

Really? I always tought that the high speed wind and large gusts could interfere with the required airflow for proper operation of the burner. No?

[avanti]

Originally Posted by Yoshimura

Really? I always tought that the high speed wind and large gusts could interfere with the required airflow for proper operation of the burner. No?

The only issue I am aware of is that driving can blow out pilot lights. But, according to your schematic, you don't have one.

Back when I had a propane heater, it was never an issue.

[Yoshimura]

Originally Posted by GeorgeRa

Your RV is new so I don’t know how much experience you have with RV water heaters. They tend to be well insulated and keep shower temperature for even 24 hrs. with burner off.

This is good news!

I have no experience yet. We'll leave the cold weather of Montreal at the end of january for a 6 weeks trip (East coast and Florida). Meanwhile, we are preparing things.

[InterBlog]

Originally Posted by Yoshimura

We need to know so we can take a shower as soon as possible after we arrive at a site. Maybe listening to the roar could work but a more convenient way would be appreciated.

K.I.S.S. principle - I set my watch timer. From experience, I have the times worked out for if I just need the water a little bit hot (e.g., doing dishes where I can use 100% hot tap without the water having been cranked up to max temp) or a lot hot (e.g., two people scheduled for shower; water needs to be hotter and mixed with cold so the tank of hot water will stretch further).

We boondock almost exclusively, so I worked out the timing system in order to conserve propane. I'm a lap swimmer and I have an Ironman on my left wrist all the time anyway (female edition). Might as well use it.

[avanti]

We love our on-demand water heater.

[InterBlog]

Originally Posted by avanti

We love our on-demand water heater.

It's been discussed in other threads, and I did a fair amount of research on the on-demand option. What I found is that that the water throughput demands of various models are too high to support a Class B boondocking scenario. Yes, they can be made to work, but they'll cost the user a lot of water in the process - water that boondockers can't afford to spare. So I stuck with the old dinosaur Atwood 6-gallon batch heater. I rarely use all 6 gallons at a time, but I can just leave the residual in there and heat it up again later.

If you've hit upon an on-demand model for which this is NOT the case, I'd love to know which one it is.

[Bud]

Originally Posted by InterBlog

K.I.S.S. principle - I set my watch timer. From experience, I have the times worked out for if I just need the water a little bit hot (e.g., doing dishes where I can use 100% hot tap without the water having been cranked up to max temp) or a lot hot (e.g., two people scheduled for shower; water needs to be hotter and mixed with cold so the tank of hot water will stretch further).

We boondock almost exclusively, so I worked out the timing system in order to conserve propane. I'm a lap swimmer and I have an Ironman on my left wrist all the time anyway (female edition). Might as well use it.

If trying to conserve propane, Don't use hot water to wash dishes! I learned this years ago but wondered, so I tried it at home. I use less hot water at home because of it.

My weak link is fresh water, so I eliminate almost all grease/fat with paper towels and use less dish soap and water....... Also the much less fat/grease in the grey water tank.

I suggest giving it a try, tap water.

Bud

[avanti]

Originally Posted by InterBlog

It's been discussed in other threads, and I did a fair amount of research on the on-demand option. What I found is that that the water throughput demands of various models are too high to support a Class B boondocking scenario. Yes, they can be made to work, but they'll cost the user a lot of water in the process - water that boondockers can't afford to spare. So I stuck with the old dinosaur Atwood 6-gallon batch heater. I rarely use all 6 gallons at a time, but I can just leave the residual in there and heat it up again later.

If you've hit upon an on-demand model for which this is NOT the case, I'd love to know which one it is.

We have an Espar-based hydronic loop that services both a water/air heat exchanger for heat and a flash-plate water/water exchanger for instant hot water. Our rig came with the Rixen's setup, but you can build your own for a lot less money.

It is just about perfect. The Espar D5 will heat the glycol loop in maybe 3-4 minutes. After that, you have true instant hot water in unlimited amounts. With a tempering valve, you get your desired shower temperature instantly, so no wasted water at all. I put in a "preheat" recycle loop for the kitchen sink, so no wastage there, either. It also has an electric coil in the expansion tank, so no need to waste diesel when you have shore power.

Don't know how it could be better for hot water. GeorgeRa has a similar system but with a separate Airtronic Espar for cabin heat. He says that it is even better.

[GeorgeRa]

There are two very different on demand water heaters. I would call commonly used LPG based “Direct” water heaters with water being heated directly in the furnace and rarely used diesel or LPG water heating via hot glycol fluid “Hydronic” water heaters. Two different animals.

A very common issue with “Direct” water heaters is that the required minimum flow is to high for small RV, just not enough water at bay. The minimum flow is dictated by a very limited flame control which could result in overheating if the water flow is too low. At low water flow these heaters safety control just keep heaters off.

A “Hydronic” water heater doesn’t have this problem, a hydronic glycol loop temperature is controlled, independently from water, within 160-180F. Water flow through a flat plate exchanger can vary from 0 to high. With 5KW Diesel Espar D5 hot water is available in just a few minutes from start for as long as you have water or fuel.

I am using Espar D5 in conjunction with the 4 gal. Isotemp marine water heater to keep hot water available at will, no waiting. Rixen system will have instant hot water with glycol loop kept hot. The advantage of D5/Marine water heater system is instant availability of 4 gal. of hot water like in most RVs. A Rixen system is much smaller and heats air too.