Delay on UFH Pump

[walsall]

Hi All,

I'm installing a building management system in a domesticproperty with UFH and sorting out the temporary lashed-in control system. Somewiring centres (like the Emmetti) have a manifold pump delay, and some like theheatmiser don’t.

Is it essential to have, or can a Grundfos UPS2 pump copehappily when running in a closed environment while the electrothermic heads areslowly opening?

I’ve seen both used, but was just wondering whether itcan do pump damage….

 

[PEG]

Hi fella,there are a few situations, where non-positive displacement circulators can run with no flow. It is not efficient,desirable,and is an indication of a poorly designed system.

Why is this pump,in your system,not returning?

 

[walsall]

Hi fella,there are a few situations, where non-positive displacement circulators can run with no flow. It is not efficient,desirable,and is an indication of a poorly designed system.

Why is this pump,in your system,not returning?

I think you've expressed what I thought. I'm going to put a delay-on timer on the pump then so that the zone valves are open before the pump runs.

Cheers.

 

[Leesparkykent]

I think you've expressed what I thought. I'm going to put a delay-on timer on the pump then so that the zone valves are open before the pump runs.

Cheers.

Cant the plumber just pipe in a bypass? I prefer to keep/build as simple as possible.

 

[walsall]

Cant the plumber just pipe in a bypass? I prefer to keep/build as simple as possible.

Agreed simple is good!
This is the pump mounted on the UFH manifold, which makes a noise when it runs before the electrothermic heads open. There's nowhere for the water to go until they open and they take a few mins. The boiler bypass can't assist with that can it?

 

[ImpededLoop]

I've wired a couple of danfoss systems recently and they both switched the pump when any of the room stats closed.

As you've said, a delay-on timer on the pump would save it pumping against a closed valve.

Out of interest, those ufh actuators don't need the pump pressure to open do they?

 

[walsall]

..........

Out of interest, those ufh actuators don't need the pump pressure to open do they?

That's a good point I'd better check that.... I'll have a play on Monday and see. The trouble is there are 4 manifolds/pumps in this room and the noise is noticeable when it starts up. Then I'll rip all the crap out. There's 21 controlled zones and the plumber 'wired' it all using 8 of those crap Honeywell chocblock boxes in a seemingly random way.

 

[EvilDrPorkChop]

I don't see the need for the pump delay? At the most it'll be a minute before the valves open and if there is 21 controlled zones is more than likely that one will be open when others are shut.

 

[Leesparkykent]

Agreed simple is good!
This is the pump mounted on the UFH manifold, which makes a noise when it runs before the electrothermic heads open. There's nowhere for the water to go until they open and they take a few mins. The boiler bypass can't assist with that can it?

Ahh got you. Is there no way of slightly altering it so the bypass could sit after the pump but before the manifold cut in between the Flow and return?

 

[walsall]

Ahh got you. Is there no way of slightly altering it so the bypass could sit after the pump but before the manifold cut in between the Flow and return?

The pump mounting is part of the manifold so not possible. Maybe worth a call to manifold supplier on Monday

 

[walsall]

I don't see the need for the pump delay? At the most it'll be a minute before the valves open and if there is 21 controlled zones is more than likely that one will be open when others are shut.

Sometimes yes, sometimes no and when its no its noisy especially when more than one is doing it.

 

[Leesparkykent]

The pump mounting is part of the manifold so not possible. Maybe worth a call to manifold supplier on Monday

Do you know the make of the manifold? Defiantly worth a call but could also have a google search.

 

[PEG]

Would be interesting to see what manifold you have,i have had "built-up" systems,which have a by-pass included. There are ,supplied multi-zone manifolds,with in-built by-passes fitted.

I have seen countless set-ups,where circulators (pumps in pub-speak),spend hours stop-ended,when valving,either thermostatic or solenoid operated,closes off flow to satisfied zones. Some protest,whilst others merely struggle on,saved only by their membership of the non-positive displacement club :shocked3:

 

[walsall]

I have seen countless set-ups,where circulators (pumps in pub-speak),spend hours stop-ended,when valving,either thermostatic or solenoid operated,closes off flow to satisfied zones. Some protest,whilst others merely struggle on,saved only by their membership of the non-positive displacement club :shocked3:

Well the pump manufacturers say "its not that good but would be OK". How about that for a scientific answer! However as it makes a noise I've had to build a panel anyway I decided to use some delay-on relays. Although as mentioned previously on the thread, simple is good, the place is so complex anyway that it needs someone intelligent to maintain everything. 32 centrally mounted dimmers, DALI, KNX, Cat6, iPad control, HDMI matrix etc etc. Not bad for a house......

Thanks all for the input.