Does radiant floor heat needs it's own circulation pump?

[MikeHege]

I put in a pex radiant floor heating system in my new concrete slab sunroom, and the hot water system that it is connected to (that heats the whole 4 story building) does not stay on long enough for it to circulate through the floor. My plumber put on a separate pump for this pex line, but I think it only runs when the whole system does, which is not long enough.
Is there a way I can set up a separate flow system that can run longer than the boiler, that can continue to circulate the hot water in the system?
Thanks, MIke

[HayZee518]

circ pump

your existing pump comes on when the system is calling for heat and its zone valves are open. it probably gets its signal off one of the control valves through a relay, so as long as that valve is open, the pump will run. for each zone you should have a zone valve and separate thermostat that operates the valve.
for your new addition, as long as your zone valve is open you should be able to use its output to energize an aux relay to run the pump and keep the burner fired.