dpmiller

So the white knob on the mixer is set to 45 yes, but... a. that's the return temperature so hot flow will enter the UFH until the return warms up to 45 b. the knob is adjustable for calibration and may not even be set right. c. are you sure the gauge is accurate? Does it read ambient when the heating has been off for some time? Turn it down to 35- or 30 even- and watch what happens when the system stabilises.

Actuators are normally slow-acting devices. The flow pulsing as it does seems too fast to me. I'd be checking that any non-return valves, pressure regulating valves, mixing valves, and pressure vessels attached to the system are all in good order as it looks more like a hydraulic resonance. Like water hammer...

^ Yep. Even the updated short red flap isn't much better tbh

chop a row of brick out and set a sill in?

why can't the original guy come back?

I've attached a document on phosphorus reduction, and PremierTech are aware of this thread following me logging in to download it. Further infos may then follow. WIJ_removal_of_phosphorus_in_off_mains_wastewater_treatment_UK-EN.pdf

^ that's not the Phosphate version, you're looking for the +P...

I have no idea. You could always try asking them?

the +P version of the Solido Smart that we installed is a single tank solution with a built-in dosing system for Polyaluminium chloride https://www.premiertechaqua.com/en-gb/wastewater-treatment/solido-smart-p-phosphorus-removal#product-description

check specs carefully- some brands need a costed upgrade to carry out Phosphorus reduction I think, and this is a fairly recent thing.

not sure if you're worried about the cost or the consumption, but an E7 tarrif might help /we've just received the last quarter's bill and for our 260m2 non-passiv it's an average of 30kWh/ day total consumption. On a cooler day a full half of that is for heat into the slab during the E7 period.

triggering DHW production 5 or 10 mins before a large demand certainly works- but it takes this long for the ASHP to ramp up in my experience.

isn't that what you're paying the removals firm for?

Inside rubber looks like it comes out first?

how does the pump know to turn on, is there level sensing in the trap or does the pump run pulling air in too?

Do it yersel.

neither cheapo gauges nor thermo actuators are known for beong terribly accurate. You can dial them all in to match a standard device if you've the time and patience...

what "rating" do they need to have?

I've used the same pump that's used on these, in a solar HW system. The pump is actually surprisingly powerful for the current involved.

so does this mean that the short heating periods youve set might not even be fully satisfying the tank currently?...

the mount and shaft *should* be universal but there are some outliers. Direction of rotation and pipe positions are the critical bit, some of the other options (position of the regulator etc) may not be so important for most applications...

tell us what burner and boiler it is, and do you know the direction of rotation? or if you're stuck there's always https://www.bes.co.uk/universal-oil-pump-16393/

no they couldn't, no smart meters in NI

*think* isn't good enough, what's the number? Buildup?

coz they fail often and drip gently. When working fine, you'll get a small volume of trapped air- at system pressure- above the internal float that'll hiss impressively when you slacken the schrader cap.