Trail Talk
Well-known member
I seem to recall articles that stated the opposite, but perhaps that was related to your second point?
Heat Recovery Ventilators
- Thread starter Trail Talk
- Start date
I seem to recall articles that stated the opposite, but perhaps that was related to your second point?
When you get a chance can you elaborate? I wasn't sure what you are referring to.
ITTOG
Well-known member
I do not know what they are indicating with "sensible effectiveness".
No because they would only be able to calculate assuming the temp was increased only by the HRV and they know it can't do that given the HRV doesn't provide raw heat as it doesn't have a heating element. To truly calculate it they have to know the heat added to the camper in the form of a rate of heat applied.
Trail Talk
Well-known member
Sorry for being unclear. While combing through online discussions, one of the pitfalls repeatedly stressed was to pay attention to claims of efficiency and note the temperature that measurements were taken. Apparently it is easier to claim higher heat efficiency when the temp difference between "fresh" and "stale", ie, inside and outside, isn't that far.
Agreed, the theory is that greater differences in temperature produce greater rates of heat transfer. It seems, however, that properly designed mechanicals makes this work or not; length of run, speed of flow, and direction of flow within the HRV seem to be critical. As I'm looking at the extreme edge of performance for these devices, I'm cautious in evaluating manufacturer claims.
Thinking about how the system applies to your environmental conditions and that the condensation drain may tend to freeze up if the port is outside of the heated envelope. Would it make sense to run the drain on the inside into a container or grey water tank?
A random alternate thought about a system that might work for you is a two component system. It wouldn't be an HRV but it would be fresh air and dehumidification.
If you don't need much air exchange to manage CO2, you could make a small insulated intake and exhaust duct and force air through with a small computer size fan or something.
The other part would be to construct a forced air duct that runs through a cool area of the camper. Maybe not directly exposed to the outside since you have really low temps but in a storage compartment or somewhere with less insulation. Part of the duct would be aluminum or a small air cooler maybe a mini intercooler with a catch basin / box to capture condensation and pipe it to a small tank. This could also run via a low velocity low amperage fan.
A random alternate thought about a system that might work for you is a two component system. It wouldn't be an HRV but it would be fresh air and dehumidification.
If you don't need much air exchange to manage CO2, you could make a small insulated intake and exhaust duct and force air through with a small computer size fan or something.
The other part would be to construct a forced air duct that runs through a cool area of the camper. Maybe not directly exposed to the outside since you have really low temps but in a storage compartment or somewhere with less insulation. Part of the duct would be aluminum or a small air cooler maybe a mini intercooler with a catch basin / box to capture condensation and pipe it to a small tank. This could also run via a low velocity low amperage fan.
Trail Talk
Well-known member
I submitted the question of managing condensation to AccuraSEE, which had my interest for their claims of -40C efficiency. Although they initially answered some simple questions, this topic was met with absolute silence! It appears their website inquiries are handled by sales so it must be inconvenient to relate info back and forth to the tech people. Or perhaps they don't like what they hear back?
Contrast this with my recent experience purchasing lithium coach batteries; I received a case number assigned to a tech person who answered every query promptly for months. IMO that is a great way for a company to establish consumer trust.
Ninelitetrip
Well-known member
@Trail Talk Any progress on your research?
IdaSHO
IDACAMPER
I love the idea, but honestly I see this as little more than a solution in search of a problem.
Our winter travel and camp experience shows that moisture & condensation control is a priority, NOT heat control/efficiency.
Some of that condensation of course comes from breathing and cooking, but most is as a result of dragging in snow on clothing, gear & dogs.
In most instances, the overall volume of a true 4-season camper is so small that when you add occupants, you need VERY little heat to maintain comfortable temps.
So little that, with two adults and a doggo or two in -20 degree weather with a tiny gravity fed 6kBTU furnace we still have windows cracked, all the while easily maintaining 65 degrees.
Our winter travel and camp experience shows that moisture & condensation control is a priority, NOT heat control/efficiency.
Some of that condensation of course comes from breathing and cooking, but most is as a result of dragging in snow on clothing, gear & dogs.
In most instances, the overall volume of a true 4-season camper is so small that when you add occupants, you need VERY little heat to maintain comfortable temps.
So little that, with two adults and a doggo or two in -20 degree weather with a tiny gravity fed 6kBTU furnace we still have windows cracked, all the while easily maintaining 65 degrees.
Trail Talk
Well-known member
Glad you’ve found a way to cope with your winter travels, as they say; “you do you”. For those who venture outside at -40, a solution is needed.
Nothing further to add in my research @Ninelitetrip, we are on the road at the moment and temps are already dropping to freezing overnight in the Yukon.
plh
Explorer
-40C is cold. The HRV/ERV efficiency is not going to be very good. The exchanger core will freeze up due to the moist inside air exchanged with the outdoor cold air and will need to run a defrost cycle. Guessing it will be something like 23C interior air out and "recovered" air "in" will be around 5 to 10C with periods of unit off or only exhausting (depends on how the defrost mechanism is setup to operate).
IdaSHO
IDACAMPER
Im talking -20F. Which is what, near -30C?
We have zero problems maintaining heat at those temps.
We have dry camped for more than a week that never got above zero degree F
And the same results.... its a moisture/humidity problem, NOT a heat problem.
And as mentioned, going further down the thermometer results in all sorts of problems.
I guess I see what you are saying.
After ski days in the Aleyska parking lot, we would crank the heat and run the fan so that we could blow warm moist air out the top of our van.
But to Trail Talk's credit, most small campers also have hot/cold spots & uneven heat distribution due to limited ducting. Cracking a window can further this problem. An HRV could allow for the same effect as "cracking a window", while also promoting air circulation through the vehicle and minimizing hot/cold spot.
Also would do it automatically for 24 hours a day, without needing a human to open/close windows.
Trail Talk
Well-known member
Post #1 of this thread: “This is where I'm at right now; deciding if an HRV would be a silver bullet for our interior frost issues in winter. “
Trail Talk
Well-known member
Dometic introduces the ACC3100 Smart Ventilation System for Europe ONLY 
12V system, fits the standard Maxxfan 14 inch opening, retails for Euro 700.
An optional air purifier module is simply an ionizing probe, not a filter; I wouldn't bother with it. Very pricy but a drop-in solution! When will we see it in North America?
12V system, fits the standard Maxxfan 14 inch opening, retails for Euro 700.
An optional air purifier module is simply an ionizing probe, not a filter; I wouldn't bother with it. Very pricy but a drop-in solution! When will we see it in North America?
rruff
Explorer
Isn't that exactly what the ventilator is for? I mean... you can open all the windows and crank up the exhaust fan, and that would surely take care of the moisture problem...? But then you'd have a heat problem. The heat exchanger warms the incoming air so you can be warm and dry at the same time. Seems like it should be a common item.