Should HRV be ON in summer without a/c running ??

[wantboost]

At what temperature and or humidity should we run or not run thr hrv in the summer months when the a/c isn't being used ?

[Admin]

Vanee says,

Setting during the summer months:
During this period, unless being afflicted with breathing problems, using the Humidity Control is unnecessary. Set the slide switch to «OFF». (Do not exchange in day time; exchange at night time, if cool outside, or if it is not raining.)

I always recommend leaving it set to intermittent, so it runs 20 minutes every hour.  This will give you enough air changes to ensure you're not breathing in VOC's.  Otherwise, the HRV will just pull in humidity that you're paying the AC to remove.  Some people leave the HRV off in the summer and only run it when they are cooking or cleaning with chemicals.

Regardless, an HRV is an energy killer but required by Code.

[wantboost]

In winter does it make the furnace run more often or helps even out heat within the home ??

[Admin]

In the winter the furnace would have to run more if the HRV is running as it is exhausting heated air and only recovers about 80% of the heat.  That's why I call them energy killers.  The HRV would have no bearing on balancing the heat.  Usually, the HRV is interlocked so the furnace fan starts when it runs, and that furnace fan operation may help balance out the heat.  The same thing can be accomplished by running the furnace fan continuously without the HRV.