[fripplfrappl]

On a radiant heat system, is it better to put circulating pump before supply manifiold or after return manifold?

[hvac1000]

Pump away from boiler is standard practice BUT I always tell people to look at the manufactures instructions for the boiler being used.

[fripplfrappl]

There is no boiler. Heat source will be a water-to-water heat pump using well water as the source and the water in the floor tubing as its load.

[hvac1000]

Now more info comes out. You did not state your somewhat nonconventional heat source. In this case I do not believe it makes a difference where you put the pump as long as it is on the opposite side of where the expansion tank is located. Good luck with your project.

[Jwson1]

I purchase a four loop rifeng manifold and as I running the tube it looks like I will need two extra loops. My question is if I buy a two loop rifeng can I hook it to the four loop to make it a six loop?