To use the HRV the way you want. You must have the Evolution control set to dehum to control the HRV. But, will only work in heating mode.
Auto, only regulates the speed, it doesn't shut it off.
If your house is dry. then you have more leakage then you think. Or you do no cooking, showering, or washing of floors, etc.
Does your humidifier work?
The humidifier works.
The HRV is rated at 117 to 189 CFM which I can measure the actual flow tomorrow. Given that I need 53 CFM continual to achieve .3 ACH then the unit needs to run for less than 30 minutes per hour.
Controlling humidity is only one aspect of ventilation. Ventilation also provides improved indoor air quality. Therefore the goal should be for one third air exchanges per hour and see what humidity is at and adjust the humidity accordingly. (either add or ventilate more to lower) When it is 25 degrees outside like now, and when you bring that air inside and warm it up it becomes very dry. It is very easy to dry out the house when it is over ventilated. No humidifier can keep up with that.
So even the LOW mode it is bringing in twice as much air as required because it runs continually. In the Dehumid mode, the unit doesn't run enough (or at all) to ventilate to the proper volume of air (.3 ACH) since the only parameter it appears to look at is the set point for the humidity. When the set point is reached the humidifier is no longer called for so it stops adding water. Therefore you will never go over on the humidity unless you cook several pots of noodles so the HRV never runs in the Dehum mode.
Are you telling me that there is no way to adjust the HRV with the Evolution control based on time on/off? (which would be the same as volume of air).
Not that I know of. I don't work with them much. But, its not an uncommon problem.
If your worried about proper IAQ. Then you shouldn't be controlling the HRV by humidity.
You should be controlling it by CO2.
.3ACH is too much, and brings your homes infiltration rating, to just about average.
Get a CO2 meter, and check your home. You'll probably find its very low, at the settings you have been using for your HRV. Doubt you'll see anything over 600PPM with it running as much as you had it running.
CO2 is a much better way to control fresh air. for IAQ. Then using the humidity.
I know of a few steamers, that will keep up with your excessive fresh air.
EWC Autoflow S2020 will.
.3 ach is over ventilating by a factor of 2 for purging indoor pollutants from the home. Based on occupants, 20 cfm per person when occupied is good. 2,500 sqft and 2 occupants need +60 cfm when occupied.
The blower door number means that during average winter conditions the 2,500 sqft. home get roughly 60 cfm of natural ventilation. Colder or more wind get more natural ventilation. During warm weather and calm winds, you get nothing. Remember the natural ventilation is added to the mechanical balanced ventilation.
Turn off your HRV turing windy or cold weather. Operate at +60 during warm, calm weather when occupied. Modulate ventilation during moderate weather. A CO2 controller would be good or shut it off during cold weather and operate when occupied during the rest of the year. This is a common problem with mechanical ventilation. Make-up ventilation only adds 50% to the natural ventilation rate. A make-up air ventilating dehumidifier is a better deal in green grass climates because it incorporates dehumidification during wet weather. Regards TB
Bear Rules: Keep our home <50% RH summer, controls mites/mold and very comfortable.
Provide 60-100 cfm of fresh air when occupied to purge indoor pollutants and keep window dry during cold weather. T-stat setup/setback +8 hrs. saves energy
Use +Merv 10 air filter. -Don't forget the "Golden Rule"
When I was researching the Infinity Control, I was frustrated that I couldn't understand the descriptions in the owner's manual. I finally found a post here with a link to a pdf file: Infinity/Evolution Sequences of Operation. It explains the settings in more detail. Have your installer get it from Carrier (good luck).
I wish I knew what professional member posted it. I wanted to thank him greatly. But the pdf file printout doesn't give me the original site.
I also have a dim memory that the HRV needs to be a Carrier/Bryant. Something in my memory about controls on that unit also come into play. You could read your neighbor's owner manual, I may be wrong. I am trying to control a fresh air intake fan, not an HRV/ERV, so I gave up on the Infinity Control. Here is what that "handout" says:
"In heating mode, DEHUM-will only turn on if indoor humidity is 3% over the set point. The speed is determined by indoor humidity and outdoor temp."
"Heating- AUTO- the ventilator runs continuously and selects the ventilator fan speed based on indoor humidity and outdoor temp. It may cycle on/off every 30 minutes depending on humidity and outside temp."
It goes on to say something if the fan coil or furnace fan speed is set to auto. I sure hopes that helps you understand your new control. In my installation, I am probably going to have a line of controllers lined up on the wall next to the Omnistat thermostat I have decided on. I haven't found out if the Omnistat has the fan cycler function I want (can't understand what the manual means). Kind of like the table full of remotes to control an audio/visual system (though I am now down to two).
Thanks for the info. It confirms what I have been beginning to understand that you really don't have much control over the unit using the Evolution/Infinity. It does not allow you to ventilate based on time/volume. Also it is a pain to change the setting. You have to open the door, go to the menu, save the setting ... no easy to reach button. I guess I will re-install the Venmar control.
Hi Energyauditor, did you ever solve this problem? I am having the exact same issue. Thanks.
I "solved" the problem by installing a separate control for the air exchanger. The control I installed has an "intermittent" function which runs the unit on low for 20 minutes and then off for 40. That works just perfectly in my situation. It also has the option to run on low or high continuously. Plus a humidity control that will override the setting to run the unit on high if the house is too humid. (The other plus is that it is really simple to use - just push the button. – no stupid door to flip open and menus to navigate)
The Evolution control does not allow this level of control over the unit. Bryant does make a stand alone control. I have a customer that just installed it and it also has an “intermittent” function. Have your installer take back the NIM and install the separate control. That is my suggestion. (They do have to run another wire …)
Remember dehumidification is only ONE of the benefits of ventilation and it may not be your primary concern. You need to be able to properly control your ventilation system. The Evolution system does NOT provide this full control to the user.
Ok. I was hoping to control it with the NIM like you had originally wanted. I do have a separate control for the HRV and wanted to simplify it with just the one control. After I had seen the intelligence that the infinity control handled the humidifier based on outdoor temperature I had hoped that the HRV would be handled with some as well . Oh well, back to 2 controllers. Thanks.
more ventilator issues
Boy am I glad I found this site, you're talking about all my dilemmas. I too have a Carrier ERV with Infinity control on my air source heat pump. I'm in NE Indiana with 6X's more heating degree days than cooling degree days, but my main humidity problem is of course in the summer. My house is extremely tight I believe, built on a slab, with sprayed foam insulation, good windows, doors, etc, all exhaust fans vented outdoors. I've questioned if I should have an HRV instead of an ERV, although I do add some humdity in the winter; not a lot. My main concern is which is going to do a better job of controling humidity in the summer, and then there's the ERV/HRV control issue. My HVAC people are trying to work with me, but they're kind of flustered too.
need to control the ventilation
Generally speaking the ERV is a better unit for your situation because it will help to take some of the humidity out of the fresh warm air coming in the house. Having the right size air conditioner and clean filters will make sure the A/C unit is running efficiently and dehumidifying as much as possible.
However, if you don't have sufficient control of the ERV and how much it ventilates then you will over ventilate and instead of drying the house out in the winter you will bring in too much warmth and humidity in the summer. On the flip side you could under ventilate the house and not get enough fresh air. I would not trust the Infinity control to ventilate correctly.
Have the contractor install the "stand alone" control. Make sure you get the control panel that provides the most options for control so you can run the unit intermittently - for example - 30 minute on and 30 minutes off. It is another box on the wall which defeats the “smart” integration into one unit. But if the “smart” unit is great in concept only, then it is dumb.
Ideally you should have a blower door test done to the house and do the math to figure out the proper run time for the ERV based on air volume and the number of air exchanges in the house. But trial and error and monitoring humidity and a “sniff test –for freshness” could work as long as you can control the runtime and run speed of the ERV.
too much humidity
I'm still not getting the kind of results I need from my ERV. Interestingly, both the ERV and HRV use exactly the same wording in their brouchures saying they will help control inside humidty, which is the primary reason I bought it. I'm using the Infinity control, and unfortunately running a wire for a seperate control isn't a real option, at least not to a location that would be best. Right now it's getting warm and thawing out outside, and just in the last two days my indoor humidty went up to 55%. I'm manually controling the ERV, but it's not helping matters any. I intend to do a blower door test this summer.
An ERV doesn't help lower indoor humidity much.
Since its designed to help maintain what the indoor humidity is. Not lower it.
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