What is hyrdrohot?

[Smoky]

I think it is some sort of hot water heating system.  I think maybe I understand it uses the diesel fuel instead of propane.

I don't think my new coach will have it but a lot of the 2006 Newmar coaches are installing it.  What are the pros and cons versus propane?

 

[Tom]

Smoky

It's a very efficient method of heating water - lots of BTUs from a very small amount of diesel. It's one thing I wish I had on our coach, but it's tough/expensive to retrofit. I've seen a similar system used for room heating on boats, but don't know if they offer it for room heating on RVs.

 

[Terry A. Brewer]

Tom

>> I've seen a similar system used for room heating on boats, but don't know if they offer it for room heating on RVs.<<

Yes it does...it replaces both your water heater & propane furnace. It's also much quieter & more fuel efficient.


Terry
At Bryce Canyon Canyon where we had a dusting of snow last night.

 

[Tom]

Thanks for clarification Terry. I forgot about the quiet aspect too.

 

[Tom]

Just remembered why the name Hydrohot didn't ring true; I'm used to it being called Aquahot.

 

[DonJordan]

Hydrohot is the trade name of the units installed by Country Coach.? It uses the same diesel burner assembly as the Aquahot but the two units work differently.? Hydrohot heats a water/glycol mix such as is used in radiators of motor vehicles.? The hot mixture is circulated through a coil in a water tank similar to a regular water heater.? I'm not sure about how they handle the coach heating but basically the hot water/glycol mix is circulated to small radiators throughout the coach where small, quiet fans blow air through them to heat the coach.

The AquaHot is similar but uses a different method of heat transfer.? The diesel burner heats a 15? or 16 gallon storage tank of the water/glycol mix which acts as a heat sink where the fluid is stored at around 190-200 deg F.? There is a coil of water pipe running through the heat sink and water is instantly heated.? There is a thermostatically controlled mixing valve on the output which sets the hot water supply to the coach at a much lower temperature (about 110 F. I think).? With this set up you have? a never ending supply of instant hot water as long as you don't run out of diesel? ;D.? The water/glycol mix from the main storage/heating tank is circulated via pumps to 3 different heating zones throughout the coach - LR, BR, and bath.? Each zone is independently temperature controlled by thermostat.? The heating is via small radiators like in the Country Coach.? Also, the heat transfer solution from the heating/storage tank can be circulated through the engine cooling system to prevent freezing and conversely the engine coolant can be circulated to the AquaHot system so that you have instant hot water when you arrive after a long day's drive.

These units are NOT CHEAP!? We PAID OVER $9000.00 for ours back in 2001 and I understand that they are now up over $13,000!!!? But they sure are nice!? ;D ;D ;D

 

[Tom]

Thanks Don. Didn't realize there were two different versions.

 

[DonJordan]

Tom,

The diesel burners of the two units are supplied by an outfit in Germany - Webasto, I think.  The rest of the parts are supplied by the unit manufacturer - I think that Country Coach makes their own while AquaHot is the trade name of Vehicle Systems, Inc.

 

[Tom]

Just found this comparison of the two systems.

 

[DonJordan]

Tom,

Thanks for that comparsion chart between the two units.  I wasn't sure whether HydroHot was a product of Vehicle Systems - this clears that up.

I forgot one other thing that our AquaHot system does - it has thermostatically controlled heating in the storage bays.  Thermostat is set for about 50 Degrees.

 

[Tom]

one other thing that our AquaHot system does - it has thermostatically controlled heating in the storage bays. Thermostat is set for about 50 Degrees.

Now that's a good feature to have Don. I have no electricity at the storage lot so, when it gets near freezing, I have to go get the coach, park it in the street, and run a power cord so my basement heater will run.

 

[Ken & Sheila]

Don,

Hydrohot is a brand name by Vehicle Systems (as is Aquahot). It is not a Country Coach  specific product as I have one in my Monaco Windsor. Monaco now uses only the Aquahot, but I think they made a mistake. the Hydrohot cost 4K less and preforms almost the same.

Both circulate a antifreeze/boiler mixture through tubes to multiple heating zone in the coach (I have 3 in the coach and one in the basement). The ho****er for domestic use is heated in the hydrohot much the same as in a direct heat oil fire boiler in a home. The is a heat transfer coil inside the boiler to heat the hot water. Hydrohot puts a circuit in the cuts off coach heat after a few minutes of Ho****er usage. This was to prevent running out of hot water. This switch can be disabled (i have and have never run out of hot water).

Ken

 

[Karl]

Here's the HydroHot website with comparisons between the two. Note the significant weight difference. http://www.hydro-hot.com/Vs.html

 

[DonJordan]

Ken,

Yes, Tom ponted out that HydoHot is also a brand name of Vehicle Systems, Inc.  As nearly as I can tell the main difference is that the AquaHot has more capacity than the HydroHot.  Note that Vehicle Systems refers to the HydorHot as the "little brother" to the AquaHot.

 

[Smoky]

Well thanks for the very nice explanations.  I wish they offered it on the Kountry Star but they do not.  Only on the more expensive Newmar coaches.

 

[Jim Godward]

Smoky,

>>Well thanks for the very nice explanations.  I wish they offered it on the Kountry Star but they do not.  Only on the more expensive Newmar coaches.<<

You may want to talk to Tom Fisher on the Newmar owners list about you installing a copy of his hydro heater.  BG

Jim

 

[Smoky]

okie dokie, I will get his address of that list and send him an email.  I see him posting there frequently.

 

[Bob McNabb]

When we purchased our new motorhome, the sales guy gushed over how we'd love our AquaHot. Having never even hearing the word AquaHot, we learned it would provide "endless hot water"....but we were "ho-hum" about this feature. We noted the cost was an added $11,000 so reasoned "This better be good !!"

We've become big advocates for the system. It's the single best feature, we agree, that is part of our new rig. Not only does it supply endless hot water, but it replaces what would have been a noisy furnace. It purrs warm air from baseboard registers. I used to be awakened by the old furnace turning on in our earlier motorhomes.

I'm 100% enthusiastic about Aquahot and have but one bad story to relate, and I caused it by my lack of understanding. There's an exhaust from the system, about the size of a generator's exhaust pipe. Our sewer drain is close to that AquaHot exhaust and I ran our sewer hose under the exhaust and returned to find it had been melted through by the heat.

The AquaHot makes short order of heating water, warming rooms and destroying sewer hoses.