Aqua Hot Issues ??

[Ck2hans]

Reading 160 Deg at all interior heating units but hot water from faucets only getting to 108 Deg.

Full disclosure: I am in New England area now and temps in 50 Deg range, normally only use coach in warmer temps.

Disassembled and cleaned Aqua Hot the other day. Everything looked good, although it did look like there maybe a small amount of dribble from the bottom of the spray nozzle. System seams to run good, no black or gray smoke at tail pipe. Exhaust is clear and hot.
108 Deg gives you a warm shower but not a hot shower. Florida boy needs hot shower in these cooler temps.

Chuck

P.S. Tank was ruptured when I purchased the coach 3 yrs ago. Aqua Hot rebuilt the tank, so tank, temp sensors and all things associated with the tank are about 2 1/2 years old.

[freds]

Look for an anti-scald valve before the shower and maybe the mixing value on the shower itself.

[Ck2hans]

Fred:

Thought of that, but water is @ 109 deg at all faucets (galley, 1/2 bath, and bathroom sink plus shower). I also turned up the mixer valve in the Aqua Hot unit to max temp 145 Deg. All faucets and shower still do not get above 109 deg, but as noted in first post individual room/area heating units do get to 155 - 160 Deg so Aqua Hot unit is producing heat but not an adequate amount in the fresh water side.

Chuck

[BadFitter]

If you have a off-on spray nozzle on your outdoor "shower" in the wet bay, be sure both the hot and cold valves are off.

[Joe Camper]

R u using city water hook up or using fresh tank water. Often city supply is way colder cold than fresh tank cold.

Also

Does running the electric element along with make any difference?

[freds]

Fred:

Thought of that, but water is @ 109 deg at all faucets (galley, 1/2 bath, and bathroom sink plus shower). I also turned up the mixer valve in the Aqua Hot unit to max temp 145 Deg. All faucets and shower still do not get above 109 deg, but as noted in first post individual room/area heating units do get to 155 - 160 Deg so Aqua Hot unit is producing heat but not an adequate amount in the fresh water side.

Chuck

What's the temperature coming out of the Aqua Hot for hot water? There's generally a heat exchanger between the glycol that runs to the heating units and the hot water. Measure the difference between water input and the output. If the unit is original to your bus, you might want to use a lime removing solution to make sure the heat exchanger portion is not restricted.

[Ck2hans]

Les
good idea about show head in wet bay. Will check that

Joe
I am running off F/W tank not city water. Can’t use electric element because I am plugged into a 20 amp outlet at my in-laws.

[Ck2hans]

Fred:
I will check the inlet and out let temps tomorrow. Aquahot tank was replaced with new tank about 2 1/2 years ago. Have used soft water every time sence new tank was installed. Unlikely calcium buildup.
chuck

[Joe Camper]

If that little mixing valve screws up that could be it.

Also Those have half in copper coiled aroud the boiler. TIGHT AND EPOXY GLUED. Critical. Over time the epoxy breaks down pipe breaks away just slightly and direct contact between the copper and the hot vessle begins to fail. It dont take much either. If u have an aqua hot that everything works as it should but no continous hot, could be some of that going on.

Those with electric elements in standard type water heaters that take back to back showers and like long hot showers, do this.

First conduct an experiment. Watching your load meters run hot water till u see a load from the heating element go on. Then stop the water note the time and see how long it will pull that load till it gets back to temp and goes off make note of how long it takes.

Then anytime u want to do multiple long showers back to back. Berore hand run the sink do some dishes or brush your teeth or something till the heating element goes on. Then wait almost as long as when u know it will limit back off and then get in before it does. It will be at max temp element on. Bam u can stand in there and melt.

The alternative is starting shower and draining half the tank off before triggering the heating element and then it cant catch back up.

And pulling from your tempered fresh tank water instead of city pressure is also easy to do with very beneficial results.

Those of u with aquahot or webasto should use them at leaste a hr or so once a month. If u r camping when its convienient to run it more frequently thats even better do it.

[Ck2hans]

Joe:
I always run off my tank and not city water. Currently at my in-laws and only have 20 amp cord for power, so no electric element for now. On that note, I have never used the electrical element and always had unlimited hot water. Something has changed.
Chuck

[twslp]

CHUCK just info i had an issue like yours. prior owner could never solve. had it to marathon and a few others. i found some materials in the water heater loop unit to unit. some white goop. cleaned every thing out. all works now. on my prior coach i lost hot water to the faucets. i had changed the washers on the bay faucet, they were thicker and was by passing. maybe my problems can shed some lite on it. good luck.

[Ck2hans]

Twsip:

What steps would I need to do to check the heater loop where you found your goop?

Chuck

[Joe Camper]

Chuck he may be refering to these being plugged up.

17918

Hes got webasto only, i think. Did they put aquahot in Marathon havet seen that. In any event. Not sure if these same valves r on aquahot these came off a CC webasto only system but ive opened these before and found them clogged bigtime. Has to be something similar on there if not same stuff.

[Ck2hans]

Problem found!

mixer valve inside AquaHot (under Wabasco motor) was allowing cold water to pass into the hot water side even though mixer was turned all the way to hot. Replaced mixer valve and all is well.
chuck

[Gil_J]

Chuck, good find. Did you isolate this with an IR gun on the hot water hose leaving the AquaHot?

[Ck2hans]

Gil
Yes I use a thermal gun to first test it. After talking to Art and Rudy, I turned off the water pump, disconnect the hot side of the stainless steel hose coming out of the Aqua Hot and into the mixer valve. Pinched the hose down to slow the flow rate, turned the water on and checked temp coming out of hose (138 deg). Temp coming from the mixer valve before disconnecting was only about 105 deg. This proved a large temp drop from inlet of mixer valve to outlet of mixer valve.
Remember from earlier in this post that I had turned the mixer valve up to max setting of 145 deg.Another thing that happened during the test with the hose removed from the mixer valve is there was a high volume of cold water coming out of the pipe where the hot water inlet was connected. With the mixer valve open all the way to the hot setting there should have been very little cold water flowing.

Chuck

[Joe Camper]

CHUCK!!!!!! Go back and read post number 9 in this thread. Sheesh

[Ck2hans]

Ya I hear ya Joe:
Got to the next line you wrote about epoxy glue may have come loose and forgot about everything else.
Would never make it on the fear factor show. LOL
Chuck

[twslp]

sorry just seen this. i see you found your problem. good deal. the loop i was ref to is at the inlet outlet fittings on my stacked water heaters. rubber molded hoses. maybe this could help another member. or could be a one and only that i seem to get a lot of.