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Topic: No antifreeze in hot side of Manabloc (Read 510 times) previous topic - next topic

No antifreeze in hot side of Manabloc

Greetings, I recently bought a 1997 U320 and having issues winterizing it. I originally blew out the lines with a compressor but after reading posts on the forums I decided to fill the lines with antifreeze as cheap insurance. I followed posted instructions regarding the the washer dryer and there is no ice maker.
I plumbed into the suction side of the pump and had no problem getting pink stuff to come out of all the cold water faucets but for some reason i cannot get any at the hot water faucets.
Through the pex I can see that all the cold water lines attached to the Manabloc are full but there is none in any of the lines on the hot side. All the Manabloc valves are open.
I do have anti freeze coming out of both the hot and cold drain valves from the Aquahot. These valves exit through the floor of the battery compartment.
I am beginning to wonder if there is a valve somewhere in the coach that I have missed.
I would appreciate any thoughts on the situation. I realize that there is a lot of information on winterizing in the forums but I haven't been able to find reference to a similar problem.
Thank you!

Re: No antifreeze in hot side of Manabloc

Reply #1 –
You have mentioned all I know of. All worked normally prior to winterizing I'm assuming. Do you get anti freeze out of the hot drain next to the tank drain? If you can't prove it is thoroughly filled with antifreeze continue to keep aqua hot powered up on ac power. Just not worth taking any risk with it. 10k$ Make sure your accumulator has been emptied by depressurization.
Scott

Re: No antifreeze in hot side of Manabloc

Reply #2 –
The tubes around the Aqua Hot hold a lot of water close all the cold valves open hot valves and see if the pump acts like it is straining if not wait longer.
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: No antifreeze in hot side of Manabloc

Reply #3 –
I've always winterized by pumping RV antifreeze into the fresh water tank.  Usually takes about 6-7 gallons.  Always have pink out of all the faucets.  Found this statement on Foretravel Wiki: "The Aqua-Hot system heats fresh domestic hot water automatically. Whenever a hot tap is activated, water is pulled from the coach's domestic water storage tank and sent to the selected faucet."  Does that mean it only pulls water from the tank/shore supply?
Glen & Suzie
1998 U320 36'
Build #5366
2015 Jeep Grand Cherokee Overland
2015 ATC Aluminum 20' Trailer
Previous 1996 U295 40'
Motorcade #17546
Stephenville, TX

Re: No antifreeze in hot side of Manabloc

Reply #4 –
Yes and it only goes out the hot water faucets.
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: No antifreeze in hot side of Manabloc

Reply #5 –
Quote from: Seven7 –
I Found this statement on Foretravel Wiki: "The Aqua-Hot system heats fresh domestic hot water automatically. Whenever a hot tap is activated, water is pulled from the coach's domestic water storage tank and sent to the selected faucet."  Does that mean it only pulls water from the tank/shore supply?

The domestic water storage supplies the AquaHot. As hot water moves to meet demand at a faucet, cold water is pumped into the AquaHot and heated to replace the hot water consumed, to supply a continuous stream of hot water...

Tim
Tim Dianics
Pam Sapienza
Vader PupZilla Labrador Canine Beast (AKA Pup)
Columbia, MO
1996 U320 4000
2021 Jeep Gladiator, Diesel

Re: No antifreeze in hot side of Manabloc

Reply #6 –
We recently moved to Indiana, this is our first year to have to worry about freezing. I installed the Camco three way valve before the water pump. I pumped about 15 gallons through the systems. First I drained all possible water then purged with air. I pumped  RV antifreeze throughout focusing on the Aquahot. At times the pump would have problems getting suction, elevating the bottle of antifreeze helped. Once it started flowing that gallon wound disappear quickly. Got good flows of pink stuff at all faucets including the outside faucet, hot and cold. I forgot about the washer, which was valved out at the Maniblock, so I put a small electric heater blowing into the washer cabinet for the really cold spells. I can also run the Aquahot if needed. I also did the Aquahot 5 year Wabesto rebuild (5 years late) after winterizing. The Wabesto had been making unusual sounds, appeared to be the nylon fuel pump gear. Bearings were still good but they got replaced, also replaced the seal in the fuel pump.
David Bethard
2003 U320 - 40ft. Build #6159
ISM 500hp
2006 Jeep Liberty CRD
2021 Honda Goldwing DCT

Re: No antifreeze in hot side of Manabloc

Reply #7 –
Cold water to the AH comes from the cold side of the Manabloc and returns to the hot side.  Close the valve between the pump and the fresh water tank, if you have drained the hot and cold lines (4 places) then sucking in pinks stuff will stop quickly.  If you then open a hot side of a faucet inside the coach pink stuff gets pumped into the accumulator, into the cold side of the manifold, through the AH, into the hot side of the manifold and out the faucet.

It is OK to get pink stuff into the accumpulator.  It is important to open each faucetor valve and the toilet, hot then cold one at a time until pink stuff comes out.  The do all of them again.  It takes 5-6 gallons for our 36'.  Maybe more if you have a longer coach and a w/d.

You don't have to put pink stuff into the fresh tank, just drain it as completely as possible. I lean the coach to the pass side to help.  You can leave the fresh tank drain valve open.  The pink stuff is potable but nasty. And hard to completely rinse from the fresh tank.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: No antifreeze in hot side of Manabloc

Reply #8 –
Thank you very much to all the great people who took the time to reply! Job done! what I gleaned from those that answered was a better understanding as to how water is distributed through the Manabloc and the Aqua Hot. It turned out that what was required was a bit more patience on my part. I pumped another couple of gallons of"pink stuff" into the system and low and behold, the pex on the hot side of the manabloc showed a nice pink glow. All the hot faucets ran pink also!
I must admit to having been very nervous about getting this done correctly and the possibility of $10,000 Aqua Hot repairs made me even more serious about getting it right :).
Thanks again! I continue to learn through this great group!

Re: No antifreeze in hot side of Manabloc

Reply #9 –
Quote from: Roger & Susan in Home2 –
Cold water to the AH comes from the cold side of the Manabloc and returns to the hot side.  Close the valve between the pump and the fresh water tank, if you have drained the hot and cold lines (4 places) then sucking in pinks stuff will stop quickly.  If you then open a hot side of a faucet inside the coach pink stuff gets pumped into the accumulator, into the cold side of the manifold, through the AH, into the hot side of the manifold and out the faucet.

It is OK to get pink stuff into the accumpulator.  It is important to open each faucetor valve and the toilet, hot then cold one at a time until pink stuff comes out.  The do all of them again.  It takes 5-6 gallons for our 36'.  Maybe more if you have a longer coach and a w/d.

You don't have to put pink stuff into the fresh tank, just drain it as completely as possible. I lean the coach to the pass side to help.  You can leave the fresh tank drain valve open.  The pink stuff is potable but nasty. And hard to completely rinse from the fresh tank.
From an old boater, a bottle of cheap vodka will take the bad taste out of the fresh water tank.
Herb and Willie
Escapees 90802
2014 IH-45 Build 6581
2002 U320 40' AGDS Build 6021 Sold
1999 U320 36' No Slides Sold
2007 Monaco Dynasty Diamond IV Sold
2005 Discovery 39 Sold
1986 20' Wilderness TT,  Died a natural death after floods, etc.
Walldog's Journeys
And Willie Said

Re: No antifreeze in hot side of Manabloc

Reply #10 –
Herb,

Is that Vodka to be taken internally to dull your taste or added to the water tank??

OK, multiple choice:

A. To be taken internally.
B.  To be added to the tank.
C.  All the above.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: No antifreeze in hot side of Manabloc

Reply #11 –
Quote from: wolfe10 –
Herb,

Is that Vodka to be taken internally to dull your taste or added to the water tank??

OK, multiple choice:

A. To be taken internally.
B.  To be added to the tank.
C.  All the above.
C. All the above.

Seriously, on a new boat we had a taste like we were drinking out of a garden hose.....a bottle of vodka in the tank cleared the taste up for us.  YMMV.

Depends on if you want to waste even cheap vodka.
Herb and Willie
Escapees 90802
2014 IH-45 Build 6581
2002 U320 40' AGDS Build 6021 Sold
1999 U320 36' No Slides Sold
2007 Monaco Dynasty Diamond IV Sold
2005 Discovery 39 Sold
1986 20' Wilderness TT,  Died a natural death after floods, etc.
Walldog's Journeys
And Willie Said