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I wonder if anyone can help me. My house has under floor heating but after having a new boiler fitted it doesn't seem to working as it should do. I wanted to get the system balanced but some of the flow meters are stuck and not all of the actuator/flow valves seem to be moving as they should. I have contacted the original manufacture of the manifold (its a JG speedfit brass manifold) and they no longer produce them and are unable to supply parts for it. I also don't know which of the 7 loops is for which area of the house so I need to identify this as well.

I think my only option might be to replace the manifold with a newer one but if anyone can offer any advice that would be great.
 
I'm not familiar with the manifold that you have but all the ones I have encountered have had standard connections for the acuators. I've had a couple of actuators fail and they are easy enough to replace, just unscrew the ring at the base and it'll just come off. Occasionally the pins in the manifold valves can stick, remove the actuator and see if you can manually press the pin in, it should spring back out by itself.

As for identifying which loop is for which room - do you have a thermostat in each room? If so, turn them all down low, switch on the heating system and then increase the thermostat temp one room at a time and feel which pipe gets hot. If you only have one thermostat then you may have all rooms connected as a single zone.

This is just from my experience as a home-owner with an engineering mindset, I'm sure a professional will correct me if any of what I've said is inaccurate.
 
The whole underfloor heating system operates using one thermostat meaning its far from ideal, this is something I will look to upgrade in the future.

I have currently set it up to heat to 22 degrees with a night temperature of 18 degrees. However despite the boiler having been on since 5.30am the room temperature is only 19.5 degrees currently.

It has a Grundfos UPS3 pump currently set to constant pressure mode 2 I think looking at the lights lit up and flashing on it.
 
Pump flashing red ?
 
did they flush the loops once they installed the boiler as they had to drain down ?
 
Do the flow meters rise and fall when the ufh pump turns on and off ?
 
Its flashing Green under the I, amber under the II and amber under the constant pressure mode.
You have it right I think but just check again that the first LED is flashing green and that the second and fifth LEDs are flashing yellow. (As PP2, if selected, wouldn't be great for UFH)

Have you any temperature readings?, ie boiler flow temp and manifold flow and return temps.

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Right sorry to revisit this so long after the original post but its that time of year and I have been using the log burner instead of the heating downstairs.

I think the issue might actually be the boiler settings. It seems to pulse the heat to downstairs rather than deliver a constant flow of hot water until the floors and rooms are hot. The hot feed pipe can be one minute too hot to touch then the next minute lukewarm even when the boiler is on.

The boiler is a Vaillant Ecotec plus 630, I am wondering if the flow and return temps might have been set wrong for a UFH system, can anyone give ay advice on the settings we need?.
 
You say in original post(s) that you have 7 loops, can you see the flowrates of each loop?, the boiler flowtemp might be 60/70C to feed the radiators if required, the UFH manifold flow/return temps might be ~ 45C/37C.
Can uou also confirm the setting of the UPS3 manifold pump, maybe post a photo of the LEDs with pump running.
 
It turns out the plumber had closed almost all the zone valves so none of them were receiving any flow. I have opened them all up a bit and the plungers now go up and down, all the flow meters are showing as receiving flow. I now just need to get the feed manifold receiving hot water flow, hopefully I will be able to sort that tomorrow when I get home from work.

The UPS3 pump flashes green on the first LED, amber on the second and amber on the fifth.
 
Around 2.5/3.0 LPM/Loop may be a good starting point, the higher the better from a boiler circ point of view, if no LLH then UFH/boiler demand of 11.72kw will result in a UFH total flowrate of 21LPM with flow/return temps of 45C/37C but this results in a boiler flowrate of only 6.0LPM with flow/return temps of 65C/37C which may present problems when boiler fires up if UFH only on, anyhow, see how it goes.
 
Around 2.5/3.0 LPM/Loop may be a good starting point, the higher the better from a boiler circ point of view, if no LLH then UFH/boiler demand of 11.72kw will result in a UFH total flowrate of 21LPM with flow/return temps of 45C/37C but this results in a boiler flowrate of only 6.0LPM with flow/return temps of 65C/37C which may present problems when boiler fires up if UFH only on, anyhow, see how it goes.

Thank you.

Are these the settings I should check on the boiler?
 
You can set the boiler flow temperature set point (target temperature),the UFH flow temperature and the individual loop flowrates, the boiler flowrate is then dependent on these settings.
 
So I think I have got to the bottom of the issues and it was pretty obvious now when I think about it but its not something I ever thought to check.

The "plumber" that has installed the new boiler has piped the flow and the return the wrong way round into the existing central heating system. The flow from the boiler is very hot and then the manifold for the upstairs radiators heats the wrong way round with flow passing through the actuator valve the wrong way and that gets hot a long time after the return is up to temperature. Obviously the heating upstairs is working fine this way as it's not fighting against a pump trying to pump water in the wrong direction.
 
What kind of UFH loop flowrates and manifold flow and return temperatures are you getting now and is the UFH system working OK on its own without boiler cycling?
 
If you only have one thermostat, then it doesn't really matter too much what setting your pump is on as it won't have to adjust to varying flow rates as all zones will presumably be on or off at the same time (unless you in the habit of manually controlling the actuators?).

Of course, you don't want the pump running on the highest fixed speed and then have to 'strangle' the flow using the flow meters, but the lowest pressure PP or CP setting that will provide sufficient flow for all circuits will do. Just my ha'p'orth.
 
Over the weekend I swapped the flow and return to the central heating system and they now have working underfloor heating. It took a while to warm the slab up but now it all seems to be working nicely.

What sort of temperatures do people have as a fall back temp for UFH? I think now its proven it works fine we will look at changing the manifold for one with working flow meters and adding stats for each room.

If they had it all fitted they would know the loop lengths to then control the flow, they don't have this information as it was all fitted so does anyone have any idea how this could be worked out? I'm guessing they would need someone with some sort of thermal imaging equipment?.
 
Tbh around the 18 mark you can go lower but will effect heat up time etc
 

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