Furnace operation with Hydro Hot

[BoDawg226]

Originally Posted by Cinequip

Lori,


Here is a summary of how your heating/cooling system works, from an Alpine owner with Hydro-hot (Aqua-Hot):


Your thermostat has two zones - front and back.. Each zone has 4 settings selected by the mode button: off, furnace, heat pump and cool. You have to manually set each zone to one of the above functions. If you need heat, select furnace and turn on the diesel hydro-Hot switch. At night, I only have electric turned on, and diesel off. The electric element is sufficient to run ONE furnace zone, without diesel on. We set the back temp to say 62 degrees (front zone OFF) while we sleep, and electric works fine. If you're driving, the engine heats the hydro-hot with electric and diesel OFF. You can have furnace heat running while driving.


If you want A/C, then select cool on one of both zones. The AC air comes out of the ceiling vents. You MUST be plugged into 50amp power to run both AC units (or have the generator running). 30amp shore power can only run one AC unit.


Our coach has heat pumps, so we can also heat by that method instead of furnace. In this mode, the AC units run and warm air comes out of the ceiling vents. This is noisier than the furnace mode, so we don't use it very often.



You've probably already discovered that when you turn on your thermostat, there is a fairly long delay before anything starts up. Also, if you are in furnace mode, whenever you use hot water the the heating fans shut off. This is due to the Hydro-hot prioritizing making hot water, instead of heating. If you want heat during your shower, you need to be in heat pump mode with ceiling heat running.


Hopefully, this helps you understand the whole package.

Thank you so much for this - and all - of the replies! This definitely helps me have a good understanding of everything. And I definitely will find the HH manual so we can ensure that we maintain the system appropriately!

[Janet and Todd]

In addition to the owners manual, I'd recommend seeking out the service and installation manuals for a complete knowledge base.

Have you fired up the unit to make hot water yet? Have you checked the level of coolant in the coolant recovery tank? Do you know when the unit was last serviced?

[BoDawg226]

Originally Posted by Janet and Todd

In addition to the owners manual, I'd recommend seeking out the service and installation manuals for a complete knowledge base.

Have you fired up the unit to make hot water yet? Have you checked the level of coolant in the coolant recovery tank? Do you know when the unit was last serviced?

Yes - we have used the hot water - both using the electric and the diesel - andbhabe also checked the coolant. I do not know when it was last serviced, so it sounds like I really need to do that.

[Janet and Todd]

Annual service is important for the health of your HH. Try to find a certified tech in your area. The tech has proprietary equipment to test your fuel pressure and check the spark. They will adjust the ignition probes for optimum ignition. They will pull the Webasto burner and change the nozzle. Proper burn is achieved by a nozzle that mists the fuel finely. Over time, fuel will enlarge the opening (which is very small) and not mist the fuel properly. The swirler will be pulled, examined and cleaned. The combustion chamber will be brushed and vacuumed. The fuel filter will be changed. They will do this with you looking over their shoulder and answer all your questions. Have them change the radiator cap and make sure they use the Danfoss nozzle also.

[Janet and Todd]

I forgot to mention that the tech will check the freeze point of the boiler coolant and make recommendations to you regarding it. Keep in mind that this coolant is different than the pink stuff you put in your sink drains when you winterize. If you buy the gallon jug of camco boiler -100 coolant, you must still thin it 50/50 with distilled water. It's the water in the mixture that will give you efficient heat transfer in the exchangers. Hope this helps.

[DrDaveMA]

One thing you need to be aware of, with the age of our coaches there is a good chance the thermostat has been changed by the previous owner. If that is the case (as with our coach) the nomenclature of the settings might be different than stated above, however the operation is still the same. You select the mode you operate in: COOLING, HEAT, with the heat pump (that was an optional upgrade so some people might not have it) AUTO if you have the heat pump and cooling or FURNACE (or Aqua Hot/Hydro Hot). Then set the temp and you are set to go.

A couple of hints on operation. If it is cold out and you are driving you can turn the heat to furnace (Aqua Hot/Hydro Hot) and if you have the circulation system (I believe all Alpine’s with Hydro Hot have it) but leave the diesel switch off. The system automatically circulates the heat from the engine and you have free heat while the engine is running. This also helps you when you park for the night, the engine heat will give you PLENTY of hot water.

You have already read the hint about about using the electric only for heat in the bedroom (zone 2), but you can also set zone 1 to heat pump, so the front will stay warm too.

Due to the noise from the roof units we run the unit in the area that we are not in to keep us warm or cool. For example once we go to bed I will close the front and open the bedroom vents forcing most of the cooling to the rear. I also leave the bathroom door open so it blocks a lot of the noise. We do the opposite during the day and at night before we go to bed.

One last trick, before we got an Oxygenics shower we would run the electric element. That would be adequate for our needs until we wanted to take a shower, the electric just would not handle the demand so we had to switch on the diesel. Once we got the Oxygenics I was able to take a shower with just the electric element, so it saves water AND diesel, who’d a thunk.....

If you are going to any of the larger RV shows there usually are certified Aqua Hot techs that will come to your coach and do an annual service during the rally.

[BoDawg226]

Thanks everyone for all the pointers. We fired up the Hydro Hot and I was able to start the furnace. Found all the vents in the coach (I think). One other quick question......where is the thermostat for the basement? I can’t seem to locate it anywhere and I wondered if someone could hope me. We are going to be headed out from Michigan soon and the temps are approaching 32 degrees at night. Thanks!

[BFlinn181]

Originally Posted by BoDawg226

Thanks everyone for all the pointers. We fired up the Hydro Hot and I was able to start the furnace. Found all the vents in the coach (I think). One other quick question......where is the thermostat for the basement? I can’t seem to locate it anywhere and I wondered if someone could hope me. We are going to be headed out from Michigan soon and the temps are approaching 32 degrees at night. Thanks!

I've not seen a thermostat in the basement that could turn on the furnace. It's one of those things they don't really tell you about winter RVing. If you don't use the furnace and instead use space heaters, electric fireplace, or even a wood stove, you won't heat the wet bay.

[BillJinOR]

Don’t have a alpine but many are not a adjustable thermostat .. they are a on off probe set at 45 or something similar. As long as the aqua hot is on .. it’s on . On my Beaver the probe is hanging from a wire fairly near the exchanger that also hangs from the ceiling in the tank bay. If you find the exchanger look for that perhaps not a adjustable “wall” thermostat.

[saddlesore]

For our coach with AquaHot... in the water management/shut off manifold/vacuum pump/water pump bay.
There is a small gizmo for setting the heat temp in all the basement bays that looks like this..(pic #2)
It is "powered/enabled" by the separate bathroom thermostat/room heat controller

[Janet and Todd]

Originally Posted by BFlinn181

I've not seen a thermostat in the basement that could turn on the furnace. It's one of those things they don't really tell you about winter RVing. If you don't use the furnace and instead use space heaters, electric fireplace, or even a wood stove, you won't heat the wet bay.

Here is the manual for the basement thermostat with a line drawing of what it looks like. Mine is mounted on the basement ceiling near the water pump which is in the smart bed bay next to the utility (wet) bay. You can also check and change your vacuum bag while down there

PS, the basement heat is enabled with the zone 2 control in the house so if you want basement heat, you'll have to run zone 2 heat in Hydro Hot mode, not roof unit mode. If you want to verify basement heat operation, crawl in there with a glass of ice water and submerge the coiled copper temp probe. This will cause a call for heat and then you can listen for the basement heat exchanger to start.

[DrDaveMA]

Originally Posted by BoDawg226

Thanks everyone for all the pointers. We fired up the Hydro Hot and I was able to start the furnace. Found all the vents in the coach (I think). One other quick question......where is the thermostat for the basement? I can’t seem to locate it anywhere and I wondered if someone could hope me. We are going to be headed out from Michigan soon and the temps are approaching 32 degrees at night. Thanks!

BoDawg, lots of info from non Alpine owners, take it with a grain of salt.

On our ‘05 the basement thermostat is located on the ceiling (location will vary by floor plan) as has been said, near the water pump. It is a brass color box with a dial (temperature setting, dial is not labeled with degrees) and a brass/copper line (ours has excess coiled up) extending from it with about a 4” bulbous ended temperature sensor. If you can’t find it let me know, I will send you a picture.

[BoDawg226]

Originally Posted by DrDaveMA

BoDawg, lots of info from non Alpine owners, take it with a grain of salt.

On our ‘05 the basement thermostat is located on the ceiling (location will vary by floor plan) as has been said, near the water pump. It is a brass color box with a dial (temperature setting, dial is not labeled with degrees) and a brass/copper line (ours has excess coiled up) extending from it with about a 4” bulbous ended temperature sensor. If you can’t find it let me know, I will send you a picture.

Thanks Dave! I found the thermostat and ours actually has numbers on it! I appreciate you (and everyone else's) help. I know have a good understanding of the furnace system / Hydro Hot.