I have a gas boiler that circulates hot water to baseboard fin heat (not radiators). It is 2 zone, and does not have the gardeen hose/check valve fittings for easy purging of air. I want to add these, and at the same time correct what I think was a reversing of the outflow/return pipes. On the current outflow, from the circulating pump, there is an expansion tank with spirovent microbubble reprocessor and automatic water feed. If I try to correct the prior mistake, the expansion tank/spirovent/water feed will be on the return side, close to the boiler. Any risk or inefficiency having the expansion tank/spirovent microbubble reprocessor/auto water feed on the return side - very close the boiler? Thanks.

For pump logevity the pump should have an arrow pointing to the boiler and on the return side. Location of auto fill device shouldn't matter.

P.S. A base board radiator or standing radiator, they are all radiators. They radiate heat.