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Topic: Aqua Hot Boiler loop fluid capacity (Read 1564 times) previous topic - next topic

Aqua Hot Boiler loop fluid capacity

I am in the process of doing an AquaHot burner service. In the process found a leak on the Engine side recirc system (which is fixed). By mistake, I drained the bulk of the boiler fluid, which appears to be the bright pink/red irradecent looking boiler type of fluid. Close but not the same appearance as my engine coolant. Peak Final charge.

 As I am to understand (and my AH makeup/overflow tank clearly states it) that the 2001 Aquahot systems are designed to work on the same coolant as is running in the Engine and the generator, I think I would prefer to have all 3 running the same fluid.

As the boiler fluid circulates throughout the entire coach for heating as well as the boiler itself, can anyone tell the approximate capacity of the Boiler system loop? I have read somewhere around 15 gallons. At the moment I've drained about half of that in a tub. Would prefer to have the fluid on hand before I finish the drain. Yes, I do plan to flush the system as changing fluid types.

2001 U295
Mike in AL
2001 U295
8.3 ISC 350
Build 5918

Re: Aqua Hot Boiler loop fluid capacity

Reply #1 –
Rudy will probably chime in but my understanding is that the same fluid as the engine was put in the Aqua Hot at the factory. Mine was a Texaco product. It is the same chemistry as the Final Charge. I don't believe you need to flush it to add Final Charge and if you drained in into a clean container as I did you can just put it back in.
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 Boiler loop fluid capacity

Reply #2 –
I agree, but what came out of it was what looked like almost new Boiler fluid...it has this bright red/pink irradecent glowing look. I have never personally seen boiler fluid, but I have seen just about any other type of vehicular fluid and never seen something like this, therefore assume it to be the Boiler type... Similar but not exact color as my final charge, but the FG does not have that same look.  If it was still the original Texaco, it would surely not look new. The PO stated they had the AH serviced a year or so b4 I bought, but could tell me nothing more.

Maybe this stuff and the Final charge are compatible, but I  wouldnt know that. Rudy might? Was just planning on playing it safe with a flush.
Mike in AL
2001 U295
8.3 ISC 350
Build 5918

Re: Aqua Hot Boiler loop fluid capacity

Reply #3 –
The fluid does not deteriorate in the Aqua Hot it would look like new fluid. It is lighter in color after water is added to the concentrate. I have no idea when mine was changed if it ever was and it was pink same as the coolant in the engine. I don't see any recommendations to change the Aqua Hot coolant that has the extended life fluid. Mine also had a sticker on the recovery bottle stating Texaco Extended life fluid.
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 Boiler loop fluid capacity

Reply #4 –
What came out definitely looks different than the Final charge. I don't have any of the Texaco to compare. As I cannot be sure what it is, and that is is definitely not the same as my Engine, Id prefer to have them all the same. I thought for sure heat transfer boiler fluid breaks down over time. I know when I used to run/maintain a waste incinerator in my pre-retired career after about 5 years it would start to break down and change color, and we always ran the best boiler chemicals we could buy in our transfer loops.

If Boiler fluid, Texaco and Final charge are all inter-mixable, and someone for a fact knows that, I'll put this back in and top it off with the FG.
Mike in AL
2001 U295
8.3 ISC 350
Build 5918

Re: Aqua Hot Boiler loop fluid capacity

Reply #5 –
Boiler fluid is not the same that much I do know. If you want it from the horses mouth send a pm to Rudy.
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 Boiler loop fluid capacity

Reply #6 –
AquaHot boiler fluid is generally potable.

Texaco ELC and Final Charge are almost assuredly non-potable and you don't want to risk those getting into your domestic hot water.

Whether you can use a non-potable fluid in your AquaHot depends on the model/design (specifically, if the design of the domestic hot water exchanger/loop (for shower, faucets) puts it at risk for contamination from the heat exchanger fluid.

You may need to check the model and serial number of your AH with Rudy.
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 Boiler loop fluid capacity

Reply #7 –
Quote from: Michelle –
AquaHot boiler fluid is generally potable.

Texaco ELC and Final Charge are almost assuredly non-potable and you don't want to risk those getting into your domestic hot water.

Whether you can use a non-potable fluid in your AquaHot depends on the model/design (specifically, if the design of the domestic hot water exchanger/loop (for shower, faucets) puts it at risk for contamination from the heat exchanger fluid.

You may need to check the model and serial number of your AH with Rudy.

My specific AH , AHE-100-02S, clearly states it can use conventional Non-potable coolant  in the boiler loop. Both my AH manual and the reservoir state it. But neither mentions the system capacity.
Mike in AL
2001 U295
8.3 ISC 350
Build 5918

Re: Aqua Hot Boiler loop fluid capacity

Reply #8 –
In an 01 Aqua Hot, the coolant for the AH is engine antifreeze of your choice split 50/50 with distilled water.  The tank holds 16 gallons.

Newer heaters with an electronic control board use GRAS (generally recognized as safe) boiler fluid or boiler antifreeze,  Only Century brand fluid is ready to use.  Others need to be split 50/50 with distilled water.
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Aqua Hot Boiler loop fluid capacity

Reply #9 –
Quote from: Rudy –
In an 01 Aqua Hot, the coolant for the AH is engine antifreeze of your choice split 50/50 with distilled water.  The tank holds 16 gallons.

Newer heaters with an electronic control board use GRAS (generally recognized as safe) boiler fluid or boiler antifreeze,  Only Century brand fluid is ready to use.  Others need to be split 50/50 with distilled water.

Rudy, thanks for the input and the Volume number. If what is in it is unknown, for the sake of the system is it ok to mix residual what cannot be drained, or best to flush?
Mike in AL
2001 U295
8.3 ISC 350
Build 5918

Re: Aqua Hot Boiler loop fluid capacity

Reply #10 –
Flushing would be the better solution especially if you are going to use GRAS boiler fluid.  I use engine antifreeze in my 2001.

Be sure your radiator cap is in good shape or just get a new 13 pound one.  Be sure the overflow hose in soft and supple and clamped to the hose barb on the filler neck and on the overflow tank.  Be sure the Aqua Hot coolant tank is totally full and fill overflow tank to hot line when the diesel burner cycles off.

You are good to go.
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas
 

Re: Aqua Hot Boiler loop fluid capacity

Reply #11 –
Quote from: Rudy –
Flushing would be the better solution especially if you are going to use GRAS boiler fluid.  I use engine antifreeze in my 2001.

Be sure your radiator cap is in good shape or just get a new 13 pound one.  Be sure the overflow hose in soft and supple and clamped to the hose barb on the filler neck and on the overflow tank.  Be sure the Aqua Hot coolant tank is totally full and fill overflow tank to hot line when the diesel burner cycles off.

You are good to go.

I wanted to go with the same antifreeze as I am using in my engine and my Generator (As you suggest). But I do not know what is in it right now...I was wanting to know if I just drained out what is in it right now, and there is residue, would any harm come to the system to just refill with the other without a flush...As clean as the system appears to be, unless I was going to a GRAS Potable friendly approach I did not see the point in a flush, But wanted to make sure. The fluid that is in it has that feel that most Ethylene Glycol based coolant have . But its physical appearance is that of a red/pink with a bit of an irradecent glow to it as light transmits through it. I have never in all my days seen an Ethelyne Glycol vehicle grade coolant physically look like this. As I myself have never had any working with the reddish boiler fluid that is Propylene Glycol I can only assume that is what it is.

However, even though I wanted to have all my fluids the same. What came out of it looks like new fluid ( PO stated he had entire system serviced in the past few years) Propylene being the more modern commonly used. I was going to just put it back in and stay with whatever IT is for now. But in the process of draining my tub overflowed and I lost a few gallons. That being said If I put that back in I will need to add a few gallons of something to get the system to the proper level.

I did just research this article, that states it is ok to mix them if you are just adding to a system, but a later statement in that same article warns about possible gelling that could cause issues with filters and strainers.I am taking this to say it would probably advise against a stronger 50Eth/50Prop approach, but small percent adding would be ok.
Can I Mix Propylene Glycol and Ethylene Glycol? – Go Glycol Pros.

I have a brand new 13psi cap as the old one had a few cracks in it, and I ha already replaced the overflow tank hose for the same reasons.
Mike in AL
2001 U295
8.3 ISC 350
Build 5918