Mark Gillespie wrote:
Tommorrow, I am lifting the floor, and planning on where to stick the
pump and maniifold, and other connection planning. I did a dry run this
evening, and connected all the bits I have up.

http://img88.imageshack.us/img88/5839/ufhpumplp2.jpg

The plumbiung is reasonably straightforward. However I have a couple
questions regarding the pump, actuators and mixer thermostat, and how
they connect up electrically and adjusted.

Obviously the actuators are wired into the thermostat somehow, is the
power to the pump also fed via the wireles thermostat control valve? Or
does is the pump powered continuously?

There is also the mixer valve, with the extended temp probe, does this
need any special considerations? It does not seem to have any
electrical connections. What do I set this to? It seems I have 2
thermostats here, one measuring the heat going out, and then the room
thermostat closing the return when the room gets too hot.

Any help/advice gratefully received!!


Not sure about your exact system, but this is how MINE is wired.


From the switched live to the whole system, I go through the timer and
the master thermostat to run the motorised valve that controls the
entire UFH.

This MV contacts run the subsidiary pump *and a relay*, whose contacts
are between switched live and the boiler/pump. You need a relay so that
e.g. calls for DHW do not start the UFH pump going. I.e. you cannot
directly parallel the UFH pump and the boiler pump.

The auxiliary pump circulates water around the UFH as long as the stat
calls for it. The mixer valve on mine is a 4 port wax capsule type
thing, that senses the flow temp in the UFH and either lets in more hot
water, or simply recirculates what is there already if its hot enough.

I have a second thermostat which sits between timer switched live output
and a couple of units that clamp on the manifold to cut the kitchen
circuits, as there is an Aga in there and extra heat is almost NEVER needed.

Somewhere I have a diagram of all this.