My home is approx. 3 yrs old. I never liked my ERV system because of the constant sound and cooling effect it had in my house. After reading about HRV systems I realized I had undedicated ERV system. The exhaust air is dedicated but not my supply. The air handler was distributing the supply air at rate of get this an excess of 1400 cfm. Pointed this out to the installer that for a house my size I should be using in the range of 200 cfm. Anyways... just another case of people not understanding anything about how things should be installed. The installer says in can install a relay in the handler that can only bring my cfm to 750. I asked about ECM air handler and was told due to the size of my air conditioner (4 tonne) an ECM air handler could only get me down to 550 cfm. My home is 2300 sq ft main level plus a full basement and one common room on an upper level about 230 sq. I really want to bite the bullet and change it to a dedicated system. I have kitchen smells that linger because I'm not using the systems all the time and I have to constantly babysitting the system to control humidity levels. Any suggestions for me? Also, we did try disengaging the air handler and letting the air find it's way through the system but the drafts out of large return grills in certain rooms was uncomfortable.

ASHRAE 62.2 calls out 7.5 cfm per occupant plus 0.03cfm per square foot of conditioned space. It takes a mighty big house to need 200cfm. Don't count the basement unless it's fully conditioned built-out living space.

Builiding Science Corp. suggests that even that number is too high, and recommend 7.5cfm per occupant + 0.01 cfm per square foot of conditioned space.

ASHRAE counts "occupant' as the number of bedrooms + 1. So a 3 bedroom 4000' McMansion would need 7.5 x (3+1) + (0.03 x 4000')= 150 cfm per ASHRAE, or 7.5 x (3+1) + (0.01 x 4000')= 70 cfm per BSC.

Sounds like you may have 2530' of fully conditioned occupied space (unfiniished basement) which for a 3 bedroom would need a bit more than 100 cfm per ASHRAE, 55 cfm per BSC.

Using heating/cooling ducts to distribute ventilation air is usually not that great even when implemented well, and it sounds like yours may be the opposite of "implemented well".

Using ceramic core ductless HRVs like a two pair of Lunos e2s place where the ventilation is most needed with might be cheaper than reconfiguring a likely oversized ERV with it's own balanced duct system. But get the big air handler out of the system entirely, if possible.

I can see why you would be frustrated with that. I am assuming the fresh air supply from the ERV dumps into the return plenum, and the air handler blower is interlocked with the ERV. What about dumping the fresh air supply from the ERV into the supply plenum, and removing the interlock? You would need to rebalance the ERV, but this would be fairly simple and inexpensive to try before anything else.
What is triggering the ERV to run as of now?
The humidity levels may be a very different issue, as ERV's and HRV's aren't made to control humidity levels, though the wrong one can make matters worse. How about some more detail on that, or a different thread?

Thanks for the responses. As of now I manually monitor humidity levels and turn the erv off and on when needed. The EVR does me no favors in the fall months; a lot of times I have to shut the erv down and run a dehumidifier. Yes the fresh air supply dumps into the return plenum. I will definitely consider the supply plenum and removing the interlock...sounds like a possible solution. Thank you.

A dedicated fully ducted ERV system is best in that it is easy to balance, removes stale air and provides fresh air exactly where needed and doesn’t use any additional electricity by having to run the furnace blower. Next best is a dedicated ERV stale air duct and putting the fresh air into the furnace return duct. This approach removes stale air exactly where desired and doesn’t require having to run the furnace blower, but doing so is ok and improves fresh air distribution. The last approach is using the furnace return duct for both the stale air and the fresh air. This approach requires at least 3 feet separation between where the stale/fresh air leaves/enters the furnace return duct and requires running the furnace blower. Further explanation and details of these approved approaches may be found here:

Ducting HRVs and ERVs

I am not aware of any approved approach that uses the supply duct of the furnace? I would think that would cause the airflow to be back driven into the ERV whenever the furnace blower operates.

You are right Sailawayrb, thanks for pointing that out!

Well, I wasn’t entirely sure that I was right which is why I made my response in the form of a question... I just haven’t seen any ERV or HRV installation manual that indicates that the furnace supply duct can be used. There are some pretty clever folks on this forum so I was thinking maybe this was somehow possible. Anyhow, it's probably best to just stick with one of the three aforementioned options unless someone has a better suggestion.