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Topic: Aqua Hot Repairs (Read 1159 times) previous topic - next topic

Aqua Hot Repairs

Probably my next big project is Aqua Hot repairs.  Two issues: first to repair a drip in an elbow in the AH that Keith Risch identified during the PPI.  It's minor but needs to be addressed.  I have plumbing soldering skills and am hopeful that it's not too difficult to get it apart so I can dry the inside of the tubing and clean it up before resoldering. 

Second issue is no hot water flow through the bedroom Cozy II heat exchanger.  I read that there's a way to bleed the line but not sure how to do that.  Looking at the top of the heat exchanger, I see what appears to be a lock nut with an adjusting screw inside the nut.  Flow regulator, bleeder valve?  I can post pictures later.
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Aqua Hot Repairs

Reply #1 –
I had same problem with bedroom unit, Rudy told me that check valve on that circuit sticks and to tap it with a small hammer.
That fixed it. Check valve is on  bedroom circ pump.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Aqua Hot Repairs

Reply #2 –
Mark, if the leak is in an accessible area you might think about using "shark bite" products. Much easier than soldering. I repaired a leak from eng circut  over a year ago and has worked great.
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: Aqua Hot Repairs

Reply #3 –
Quote from: rbark –
Mark, if the leak is in an accessible area you might think about using "shark bite" products. Much easier than soldering. I repaired a leak from eng circut  over a year ago and has worked great.
The shark bite is interesting.  Looks similar to the push to connect air fittings.
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Aqua Hot Repairs

Reply #4 –
Quote from: jcus –
I had same problem with bedroom unit, Rudy told me that check valve on that circuit sticks and to tap it with a small hammer.
That fixed it. Check valve is on  bedroom circ pump.
Thanks for the idea.  Keith tried it when we were doing the inspection but it's worth another try.
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Aqua Hot Repairs

Reply #5 –
It could also be the relay for that zone. Does the pump run. Sometimes the relay works loose or else might have failed. If the pump is running then I would think the check valve is stuck.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: Aqua Hot Repairs

Reply #6 –
Regarding the AH leak, when we got home from Destin, FL yesterday (about 375 mi.) had a good amount of what appears to be red coolant on the floor of the AH / diesel tank compartment.  This morning I've been searching and reading posts on AH repairs.  Once again I'm thankful for the body of knowledge here on the forum.  One thing I learned is I'm glad our AH is located on the edge of the coach instead of in the middle as it was in some earlier models. 
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Aqua Hot Repairs

Reply #7 –
Quote from: Mark Duckworth –
Regarding the AH leak, when we got home from Destin, FL yesterday (about 375 mi.) had a good amount of what appears to be red  coolant on the floor of the AH / diesel tank compartment.  This morning I've been searching and reading posts on AH repairs.  Once again I'm thankful for the body of knowledge here on the forum.  One thing I learned is I'm glad our AH is located on the edge of the coach instead of in the middle as it was in some earlier models.
Search Roger Burke's site there is mention of some O-rings that leak on the pumps of certain models. That is where I got my information When I had a Monaco and didn't belong to the forum. He even has a premium section that if you buy parts you become a member. I paid this time to become a member as I didn't need any parts when my membership ended.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Aqua Hot Repairs

Reply #8 –
Had time today to dig into the AH leak.  Actually looks like I have 2 leaks.  One is in the engine coolant return line in photo 1.  I believe I'll try rbark's suggestion of a shark bite replacement elbow. 

The second leak is in the diesel supply elbow in photo 2.  Looks like the elbow and nipples need to be cleaned and reassembled.  I wonder if they forgot to use thread sealant.

Photo 3 shows a brown colored cable.  Its jacket surface is sticky and gooey.  Is this a known issue?

There is a heat exchanger in the passenger side water tank / pump bay.  It's controlled by a thermostat in the same bay.  Is that heat exchanger on the same loop as zone 3 (bedroom)?
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Aqua Hot Repairs

Reply #9 –
Quote from: Mark Duckworth –
There is a heat exchanger in the passenger side water tank / pump bay.  It's controlled by a thermostat in the same bay.  Is that heat exchanger on the same loop as zone 3 (bedroom)?

Mark,

That heat exchanger should be on zone 2 the one that has the heat exchanger for the bathroom.

That gooey cable cover could be from the diesel leak. Our cable jacket is the same way and has been that way for years. It hasn't come apart and hasn't had any effect on the 4 wires that it covers.

Pamela & Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Aqua Hot Repairs

Reply #10 –
Quote from: Pamela & Mike –
Mark,

That heat exchanger should be on zone 2 the one that has the heat exchanger for the bathroom.
Thanks.  Good to know.  I want to make sure it's working before winter.
Quote from: Pamela & Mike –
That gooey cable cover could be from the diesel leak. Our cable jacket is the same way and has been that way for years. It hasn't come apart and hasn't had any effect on the 4 wires that it covers.
In that case I shall let sleeping dogs lie.  ^.^d
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Aqua Hot Repairs

Reply #11 –
Mark, here's a picture of my repair. Looks like it's the same elbow. Known to crack at the elbow. This pipe comes from the circulating pump ( left side of pic ) then into the aquahot. Almost impossible to solder a new elbow back there. The cork is a spacer/support for that copper line.
 Hope this helps.
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: Aqua Hot Repairs

Reply #12 –
Quote from: rbark –
Mark, here's a picture of my repair. Looks like it's the same elbow. Known to crack at the elbow. This pipe comes from the circulating pump ( left side of pic ) then into the aquahot. Almost impossible to solder a new elbow back there. The cork is a spacer/support for that copper line.
 Hope this helps.
My cracked elbow is on the right side when I'm facing the unit. It's the return line for coolant going back to the Cummins engine.  Nevertheless I'm exited to try the shark bite.  Thanks again for telling me about them!
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Aqua Hot Repairs

Reply #13 –
I was sitting here reading the package for the JB Weld Waterweld product I bought today to repair our utility bay faucet.  It strikes me that this product claims to be good for copper as well as brass.  Seeing's how the AH elbow is already cracked, I'm thinking about trying the WaterWeld product on it too.  I've got nothing to lose except an hour or so.  Might be a fun experiment.  Perhaps not a permanent solution but what if one of us were in the middle of nowhere and our AH sprang a leak.  It would be nice to have quick fix until we could do a proper repair.
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Aqua Hot Repairs

Reply #14 –
The water weld will probably work but make sure there is no fuel residue where you are trying to repair.
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Lynn & Marilyn Sickel
Tollville, AR
1997  U320  40'
2021 Chevrolet Silverado pickup
Motorcader  17257

Re: Aqua Hot Repairs

Reply #15 –
Quote from: Forewheelers –
The water weld will probably work but make sure there is no fuel residue where you are trying to repair.
Good point.  I'll make sure to clean it really well.  Prior to application I think I'll take a bronze brush and get the oxidation off of the surface too.
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Aqua Hot Repairs

Reply #16 –
Progress report.  Cleaned the AH and then took the Dremel tool and took the copper elbow until the oxidation was removed.  I then applied the Waterweld epoxy putty.  We'll see tomorrow or the next day how it's holding.

I left the edges of the elbow free of epoxy in case the fix fails. Then I can go the elbow replacement route.
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Aqua Hot Repairs

Reply #17 –
Simple fix for that elbow is the carry a male to male hose connector and pull the lines from the engine leading into the AH and back to the engine and bypass the whole unit for a quick fix on the road. I had to do that twice.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: Aqua Hot Repairs

Reply #18 –
Quote from: John S –
Simple fix for that elbow is the carry a male to male hose connector and pull the lines from the engine leading into the AH and back to the engine and bypass the whole unit for a quick fix on the road. I had to do that twice.
That is a great idea!  I'll add those parts to my list.  Thank you!
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Aqua Hot Repairs

Reply #19 –
I'm bummed out. While the epoxy putty held ok under hot coolant flow, it wasn't the only leak.  I worked on the phone with Rudy and we're pretty sure the second leak is in the engine coolant heat transfer coil inside the AH. Rudy says the cost for that repair is mega coach bucks.

So.....  At this point the engine coolant lines are in bypass mode.  Needed those parts John mentioned above a little sooner than I thought !!

Good news is the AH is heating fine.  All 3 loops and the water tank bay heater are working well (previously the BR loop wasn't heating).  I lost my engine preheat function along with engine heat to AH benefit. Rudy and I discussed plumbing the coolant lines back to their original config but with the addition of some shut off valves that will let me run the coolant in bypass mode except in an emergency.  If preheat is needed and I'm willing to drip a little coolant then I can flip the valves to get the preheating done.  Jury's out on that for now.

Like I said, bummed.
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Aqua Hot Repairs

Reply #20 –
Mark, since you're a hands on guy I'll point out that at least one member successfully rebuilt the loop in his aquahot using standard hardware.  Trying to remember who it was, Canadian guy with a 320, sold it recently.  Maybe someone else will recall....
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: Aqua Hot Repairs

Reply #21 –
Quote from: Chuck Pearson –
Mark, since you're a hands on guy I'll point out that at least one member successfully rebuilt the loop in his aquahot using standard hardware.  Trying to remember who it was, Canadian guy with a 320, sold it recently.  Maybe someone else will recall....

Aqua hot Rebuild
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320
 

Re: Aqua Hot Repairs

Reply #22 –
Quote from: Chuck Pearson –
Mark, since you're a hands on guy I'll point out that at least one member successfully rebuilt the loop in his aquahot using standard hardware.  Trying to remember who it was, Canadian guy with a 320, sold it recently.  Maybe someone else will recall....
Chuck,

Just finished reading that post (thanks, Michelle)  Since it's the coolant line on ours and not the fresh water line, there's a good chance our loop didn't burst.  I would venture a SWAG that it's a connection between the externally visible 1/2" tubing and the coil inside. Just a guess.
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971