Water heater motoraid

JBP · 04-10-2019, 03:58 PM

Does your Vista Sunstar 30T motoraid hot water heater get hot with just engine heat?
If so how hot approximately?

bobmac · 04-10-2019, 05:09 PM

On my 09 Journey, I could not differentiate the temperature from the motoraide from that from the water heater. The motoraide is very efficient.

snooper · 04-10-2019, 05:30 PM

works great... need about 50 miles/ 45 minutes for "hot" water....

winnie32v · 04-11-2019, 05:41 AM

Quote:

Originally Posted by JBP

Does your Vista Sunstar 30T motoraid hot water heater get hot with just engine heat?
If so how hot approximately?

Cooling water from the engine is shunted to the back of the water heater and makes physical contact to the metal heater housing, thus transferring heat from the engine coolant to the heater shell and this heats the water in the tank to the same temperature as the engine coolant. This is usually around 185 - 190 deg F. (Depending on the function of the thermostat in the engine.)

I always have a full tank of hot water after we stop in the evening.

Also associated with this hot water heater is the Coach Heater which also pulls heat from the engine coolant via a heat exchanger and distributes it throughout motorhome using the floor heating ducts. (Same ducts that the propane furnace uses) We are never cold when we leave Pa. as winter approaches and it is cold outside.

JBP · 04-11-2019, 06:16 AM

Thank you. First coach with this system. Is there a switch that needs to be throne to work the system?
If not my system does not seem to work. After 290 miles the temp seemed almost the same as the cold water.

winnie32v · 04-11-2019, 06:42 AM

Quote:

Originally Posted by JBP

Thank you. First coach with this system. Is there a switch that needs to be throne to work the system?
If not my system does not seem to work. After 290 miles the temp seemed almost the same as the cold water.

OK, Time to investigate.
No, there is no switch in my unit, don't know if there was an option in other units OR if someone put one in.
So,
Remove the engine cover and trace the coolant lines and try to determine if there are lines going in the direction of the Hot Water Tank. My tank is just behind the right front tire and you can also see the hoses if you look from under the wheel well. Not sure where yours is....advise, please.

And/Or,

depending where your Hot Water Tank is located, look at the back of the tank (Using direct site, mirror, or feel around) to determine if there is a coolant line interface that would be welded to the back of the tank. A rubber coolant hose would be going into and out of this interface. I have attached a photo of the back of my tank. This was taken when I removed my tank to replace a broken fitting. Look at the bottom of the tank for the coolant hose attachment nipples.

Note. Someone may have "unattached" the hose(s) going to this tank.

....all I can think of for now, I assume that your Hot Water Tank check valves are working ok, should be if you get hot water from propane or electric heat sources.

Please advise what you find.................

tderonne · 04-11-2019, 09:59 AM

I found the specs for a 2018 Sunstar LX, it shows the 30T floorplan, is that what you have?

2018 Sunstar LX Specifications

It shows it has Motoraid, in the plumbing section, is that part of your question?

snooper · 04-11-2019, 10:53 PM

I have a 2010 vista 30W... my hot water tank is between between the kitchen sink and bathroom... access is under the kitchen sink... my water in the tank heats up from the engine coolant... takes about 30 minutes after the engine is warm... there is no shut off valve that I could determine.... I had to replace the electrical heating unit and observed the coolant hoses connected to the water tank (not related to the electrical element)...

powercat_ras · 04-12-2019, 10:41 PM

I have a 2015 Vista 27N with MotorAid DSI hot water heater and have instrumented my Hot Water Heater with temp monitor at the hot water outlet. After driving several hours the hot water temp will be well over 120 F when driving in cold weather and around 140 F when driving in hot weather. Hottest I have ever seen after driving is 145 F. Less than 2 hours and the water will be a little less than this. It seems to be engineered so that there is enough heat loss between the hot water port on the engine and the hot water heater so the hot water temp can't get much hotter than what the hot water heater thermostat itself takes it to , which is around 140 F.

JBP · 04-13-2019, 12:18 PM

As always thank you guys for all the information. I feel much more informed now.

Richw · 04-17-2019, 05:31 PM

I have a 2018 Vista LX 30T with the motoraid water heater. When I first got the motorhome the dash heater did not work. The motoraid water heater is in series with the heater core for the dash heat. The heater hose running back to the water heater makes a couple transitions from rubber hose to metal tubing and back. I found a kinked rubber hose below the water heater. It was located in the storage compartment that the sewer dump is in where the metal tubes switch to rubber hose. After fixing the kink I found the antifreeze level went down because the lines going back were never filled due to the kink. The motoraid water heater works great.
Rich

danhannah · 04-17-2019, 07:25 PM

If it is hooked up, and hoses are not kinked, it can get EXTREMELY hot. Maybe 140 or so. There is no way you would not notice the difference, if it is working. It is not at all subtle.

Winnebago reversed the hot water coolant lines from the engine to my dash heater when they built my rig - so the dash AC never worked well, and the dash heater never regulated temps. Man was that hard to find....

So in tracing the lines, looking for kinks, etc, check if the hoses are flowing the right direction as well.

DryCreek · 04-17-2019, 07:49 PM

Quote:

Originally Posted by Richw

I have a 2018 Vista LX 30T with the motoraid water heater. When I first got the motorhome the dash heater did not work. The motoraid water heater is in series with the heater core for the dash heat. The heater hose running back to the water heater makes a couple transitions from rubber hose to metal tubing and back. I found a kinked rubber hose below the water heater. It was located in the storage compartment that the sewer dump is in where the metal tubes switch to rubber hose. After fixing the kink I found the antifreeze level went down because the lines going back were never filled due to the kink. The motoraid water heater works great.
Rich

Well, that makes for an interesting question - if you run all day with your AC in MAX cool position, the vacuum operated valve to the heater core will close. Does that mean that your water heater will not warm up?

NeilV · 04-17-2019, 07:52 PM

According to the owners manual for your coach a Vista LX 30T there might be an Optional MotorAid Water Heater in your coach and the specification is that it will heat up to normal temperatures in about 100 miles of driving. There are no switches to turn MotorAid on or off according to the manual.

See around page 56 in your operators manual and the water heaters booklet included in the Winnebago InfoCase for your motor home.

https://winnebagoind.com/resources/m...18Vista_LX.pdf