ERV as intake to solve tight house/power vent gas appliance problems?

[racer766]

One of the future projects I've been thinking of is a erv or hrv to vent the house. Will these also allow air to flow to makeup combustion air blown out as exhaust by a powered vent water heater?

The furnace will be sealed combustion (intake/exhaust) by the end of the night. I'm trying to choose a water heater. If I can use an erv or hrv to makeup the water heater combustion air I can go with a much less expensive power vented (exhaust only) water heater. The reduced cost of the water heater would almost pay for a small, unpowered, furnace add-on hrv.

I have space in my mechanical area to do this, and can run windward/lee side vents without a problem.

[Jay11J]

No, these are balanced sytem.

What it is taken out of the home, is the same that is brought in.. it not going to add any "extra" air into the home.

[racer766]

I don't understand. Does it have a volume-displacement pump in each direction, like a roots-type blower for a car supercharger? All of the diagrams I've seen have a crossflow heat exchanger, maybe with axial or squirrel cage fans.

Do they have mechanical vents that seal when not exchanging air?

[Jay11J]

The air passes over the exchanger.. they are not mixed in away (some may only in defrost)

When the system shuts down there is a damper the cloeses off the outside air.

Both blower moves the same amout of the air in and out.