New tankless water heater

[RankAm]

Originally Posted by VintageRV

I just got off the phone with Girard's General Manager, Jerry Rennert. Here's how they address the issue we've been talking about. This is regarding the instructions with the heater to use only the hot water and not the cold...

If you use more water it cools, if you use less, it heats. If you mix in cold, the heater will shut off repeatedly because the small amount of water flowing through the burner will hit 122 degrees and will trip the limiter. Then it will cool and it will try again. Basically, you need to run about 1 gallon/minute through the heater to keep the water cool enough to keep running. That's why they don't want users to get in the habit of mixing. On this same note, if you are trying to really conserve fresh water and trying to just use a trickle of warm water, it really doesn't work and you'll be happier with a tank heater.

Also, remember when judging the btu ratings that trailers basically have about 80K btus available because of the regulator. So if you are camping in cold environments and have the furnace on, you will not have that full 80K available to any water heater.

I'm happy to clarify if I haven't. Thanks.

So, Steve, that means we should plan for a shower of high volume but of short duration?; possibly several shower intervals of high volume but of short duration (one to soap and one to rinse)?

Thanks for providing the information. Hank

[DanielB]

Somebody will get it right eventually. I'll stick with the foot tub for now and wait them out..

[pmclemore]

If you want to conserve fresh water and gray water capacity, you will be much better off using a tank water heater. It is no effort to flip the on switch before you need it and then turn it off when you are finished.

I have a Rennai water heater at home and love it, but using it also teaches you that it is less than optimal for an application where you are not connected to city water and a drain.

Pat

[alclad]

the precision temp rv 500 works for us. requires the space of the larger atwood ~10 gal. heater. water pressure with 12vdc = lots of hot water

[Gene]

Since RV shower heads have a setting that lets a small amount of water flow to conserve water when you don't need full flow, it sounds like a tankless heater would perform well then—it might get really, really hot.

Some of the one piece mixing valves common to newer showers in homes or RV's don't mix water well when the water volume is significantly reduced either. Sometimes we get cool or cold water, sometimes it's too hot, sometimes is close to what we want.

If I ever have to replace the mixing valve in our trailer, I may use an old fashioned solution—separate hot and cold valves. The tankless system seems to be of limited use in an RV unless the RV never moves and always has plenty of city water and a drain.

In reading about tankless heaters for residential use (I thought about it for a house some years ago), I've never heard about not using the cold water but regulating temp through water volume. This appears to save fuel for hot water, but waste water, also an ever more expensive resource and one of limited amounts in the west. This has been useful information and I'm glad for this thread.

Gene

[bill h]

Originally Posted by lewster

Just finished reading the installation manual. The rough opening for the Girard Tankless water heater is 12.5" X 12.5" X 13.5" deep. There is a flange that attaches to the outer skin and the door fits into the flange.

Of interesting note: The instructions say the following:

*DO NOT TURN ON THE COLD WATER
*Turn on Hot Water to a Normal Flow
*Adjust the Hot Water Flow to achieve the desired temperature
*Gradually DECREASE the Hot Water Flow to RAISE the Hot Water Temperature
*Gradually INCREASE the Hot Water Flow to LOWER the Hot Water Temperature

From reading that, I'm gonna guess that this unit is not suited to an RVer who conserves water by changing (or interrupting) the water flow during the shower.

The Paloma of 25-30 years ago was that way, too. The water temp stayed set only if the flow was constant. Fine for a house or a hooked-up RV, but not a boondocking RV.

[lewster]

Originally Posted by bill h

From reading that, I'm gonna guess that this unit is not suited to an RVer who conserves water by changing (or interrupting) the water flow during the shower.

The Paloma of 25-30 years ago was that way, too. The water temp stayed set only if the flow was constant. Fine for a house or a hooked-up RV, but not a boondocking RV.

I have used a Precision Temp RV-500 for 10 years in 2 different RVs. When trying to conserve water (especially in my '06 19CCD), I would rely on the on/off valve installed at the shower head. Set the water temp where you want it and rinse down, then shut the flow with the valve. Soap up and then open the valve (actually a little push button on the restrictor) and rinse off.

It's that simple and the water temp would be just right. Conserving water with a tankless is not difficult, and I might add that I'm sure that I did not use more water than if I had a tank-style water heater. One thing is certain: I surely conserved a TON of propane, as I would barely go thru 2 30# tanks in 3+ months of full-timing in the A/S.

[Gene]

Lew, that's not the way our showerhead works unless I am misunderstanding your post. When we push the slide valve the water flow is reduced, by not stopped. We went through 3 OEM showerheads (the cheap Airstream one kept breaking, they kept replacing it) and each restricted flow, though each restricted to a different amount.

When the last one cracked and the warranty was up, we bought one for less than $20 at Lowe's. It's a much better showerhead with several settings including one with restricted flow. It took a while to find one at Home Depot and Lowe's restricting flow, but we didn't want to get it at an RV store because we figured quality would be low and cost high.

I could have looked for a separate shut off to install in line, but found a shower head before I started looking for that. Perhaps if I had a tankless water heater, that would be the way to go.

Gene

[lewster]

I used an add-on shut-off valve that attached to the shower head. the RV style shower heads are designed to 'drip' (all of these 'drip' at different volumes) to remind you that you have left the shower mixing valve open and that the water is still flowing.

The shut-off that I used would completely block the flow of water to the head until you released it.............no 'dripping'.

[Gene]

Lew, makes sense. I wish I had thought of that before I went looking for a non-RV showerhead that had restricted flow.

By the way, I'm glad you are still around. A lot of people give advice here, and some can be trusted, and some not, but I believe you are more knowledgeable than most anyone.

Gene

[bill h]

Originally Posted by lewster

I have used a Precision Temp RV-500 for 10 years in 2 different RVs. When trying to conserve water (especially in my '06 19CCD), I would rely on the on/off valve installed at the shower head. Set the water temp where you want it and rinse down, then shut the flow with the valve. Soap up and then open the valve (actually a little push button on the restrictor) and rinse off.

It's that simple and the water temp would be just right. Conserving water with a tankless is not difficult, and I might add that I'm sure that I did not use more water than if I had a tank-style water heater. One thing is certain: I surely conserved a TON of propane, as I would barely go thru 2 30# tanks in 3+ months of full-timing in the A/S.

Sounds pretty good. Way better than my Paloma. I wonder if the Girard will be as good.

[lewster]

I have one in the box sitting on my bench. I'm hoping to do a sets next week. I'll keep this thread posted.

[AndrewM]

Any updates on this Lew? I am thinking of pulling the trigger on one today or tomorrow and would like to know which one to shoot for.

Thanks

(I am not sure why i used rifle references?!)

[chriscrimmin]

Originally Posted by AndrewM

Any updates on this Lew? I am thinking of pulling the trigger on one today or tomorrow and would like to know which one to shoot for.

Thanks

(I am not sure why i used rifle references?!)

In reading this Andrew, I think you should aim for the Precision temp or the DSI atwood 10 gal. From one brother to another.

[masseyfarm]

My thoughts. Correct me if I'm wrong.
Tankless is probably the way to go if a replacement is needed for your trailer, but a questionable expense if just upgrading.
The advantages for a trailer are far greater than for powered unit.
There would be a weight saving of 60# + on a 6 gal tank.
However, for a powered unit, the opportunity to use/install an engine coolant heated tank gives you FREE hot water anytime you are travelling.
Many of the lighter powered units would benefit from the weight factor, but the large units weight is generally not a problem.
The problem with installing a 10 vs a 6 gal. is you are carrying another 40#, (dead weight that can't be used) and although more hot water to start, it takes longer to recover.
Dave

[Breadbug]

Originally Posted by masseyfarm

My thoughts. Correct me if I'm wrong.
Tankless is probably the way to go if a replacement is needed for your trailer, but a questionable expense if just upgrading.
The advantages for a trailer are far greater than for powered unit.
There would be a weight saving of 60# + on a 6 gal tank.
However, for a powered unit, the opportunity to use/install an engine coolant heated tank gives you FREE hot water anytime you are travelling.
Many of the lighter powered units would benefit from the weight factor, but the large units weight is generally not a problem.
The problem with installing a 10 vs a 6 gal. is you are carrying another 40#, (dead weight that can't be used) and although more hot water to start, it takes longer to recover.
Dave

I'm confused. Engine coolant powered water heater?

Ed/Breadbug

[masseyfarm]

On the motorhomes,("powered units") many have a heat exchanger on the water tank so that you have hot water when you get to you destination, or at any stop.
Dave

[au_ee]

Originally Posted by Breadbug

I'm confused. Engine coolant powered water heater?

Ed/Breadbug

Me too. Engine coolant/water heat exchangers are common in many motor homes. I haven't heard of this concept being tried in a travel trailer.

[1963tradewin]

Check out Precision Temps web site for the Twin temp JR its a heater and water heater in one package. Its expensive, but nice set up if you want top of the line. Don't know if this will help, but thought I'd throw it out there! Im thinking of going with a rv 500 or a Girard. My question is: Does anyone know if Girard comes with a polished aluminum door like the rv 500 does, or do they come in just white?

[Aage]

Lew,

Are you talking about the Girard GSWH 1? That looks like a mighty sweet machine, and it's not badly priced, from what little I could find.

And here's me with a new regular one, only a year old :/