Ricco

I would be interested to hear what Heatmiser support said, they wern't overly helpful when i was last in touch with them about my odd issue! So i have a fix!!! After trying everything i could possibly think of i gave up and taped a piece of cardboard over the one in my daughters room and sort of forgot about it for the past year and a bit. The cardboard got knocked and the backlight was annoying my daughter, so i took to it again. I unscrewed the circuit board from the front display and removed the 5 metal contact that make the touch sensitive "buttons" work. I put it back together (the thermostat cannot be adjusted in the room now, but it's not an issue as i always use the app) and no more illuminating of the back light. Give it a try, and let me know if you have the same success.

Hi We completed and moved into our house in the spring, so are only having to use the heating now. This is the first time we have ever had UFH so we are still getting used to it. We have UFH throughout with a liquid screed, we have a good amount of insulation and a good level of air tightness. My question is in relation to its operation - should i keep a constant room temperature 24/7 e.g. 21 degrees or use the set points in the room thermostats to set it back to say 16 degrees when out at work or not using the room. I have read that UFH should be run all the time but i was unsure if this meant to maintain a constant temperature or vary the temperature. Any advice would be appreciated. Thanks

So the sage continues!! Some of the thermostats continue to randomly light up and i have tried the following to get it fixed. The problem stays in the room when you swap the face plate or back plate with a room that doesn't light up on it's own. I have changed the wiring to use different pairs. I have removed it from the back box and allowed it to dangle down the wall away from the metal back box. I have turned off all WiFi. I have turned off the NEOHUB so the mesh network is not in force. I bought ferrite beads to put round the CAT 6 cable at both ends and it made no difference. I bought ceramic capacitors and installed a 100nf across the 12V ports on the thermostat I got the supplier to swap out the thermostat and i replaced the back plate and thermostat I got a new wiring centre and swapped it out. I installed a new CAT5 cable following a route through the loft not close to any other cables. I installed a new shielded CAT6 FTP cable through the loft and also followed a route that it did not run along side other cables or cross them. I used the wire in the shielded CAT6 and earthed it and earthed the metal back box I turned off every circuit in the house (except heating) and it continued to flash. I connected a flex and a plug top to the mains supply of the wiring centre so it was powered by a different circuit and it continued to flash. I connected it with a CAT6 patch lead run through the landing and it stopped flashing, so to identify if it was the cable or the route i got the previously installed CAT5 cable out of the loft and connected it through the landing and it only flashed once!!! So any suggestions would be appreciated as having the cables lashed across the floor of the landing is not exactly ideal!!

Would a higher rated ceramic capacitor make any difference? Is the train of thought RF interference / electrical interference as the cables do share trunking with 240v cable for a bit or some sort of voltage drop over the run of the cable?

So.... the saga continues... I have installed a 100nF ceramic capacitor between + & - at the stat but no change :( Any other suggestions, should i try more than one capacitor in the stat?

Thanks for this... the wiring seems to be correct as you have suggested. A ceramic capacitor is something I haven’t tried, what would this do? Would linking the + and - not short it out?

Hi Heatmiser support have been unable to give me any indication as to how the proximity sensor works. i tried something last night which has been the first successful test.... I wired the master bedroom stat into the wiring centre with a long CAT6 patch cable running up the corridor from the bedroom to the wiring centre. This worked and once reworked the back light did not illuminate on its own! So.... what i am trying to figure out now is how to make the fix permanent (the wife said she is not happy with patch leads running up the corridor!!) The cable must be picking up interference and causing the back light to illuminate. The electrician who wired them in used CAT6 unshielded cable with a plastic spline running up the cable to keep the pairs apart (not uncommon for CAT6) this was probably because I was getting the data points wired with CAT6 He said he has used CAT5 or 6 cable to wire these in before with no problems. The cable I have used for testing was a CAT6 patch lead so doesn’t have the spline in the centre, so don’t know if this means with the cables being closer together it aids in the cancellation of any interference. The instructions say it should be wired with CAT5-FTP ( not just shielded but each twisted pair having a foil wrap) or BELDEN 9538 cable. Because rewiring won’t exactly be an enjoyable task I want to do it once but not cost myself the earth with specialist cable. Would normal UTP CAT5 without the spline do? Or potentially just change the route of the existing cable (if it’s length permits)

Hi I have 15 Heatmiser Neostats installed in the house (7 downstairs and 8 upstairs) split across 2 wiring centers. The problem have been facing is that the back light on some of the thermostats comes on randomly when you are nowhere near it. This doesn't sound like a massive problem when you type it out, but lying in bed at night and the room lighting up is not ideal! It is happening in 3 bedrooms, ensuite, hall and living room. I have tried almost everything but am nearly out of options. The problem stays in the room when you swap the face plate or back plate with a room that doesn't light up on it's own. I have changed the wiring to use different pairs. I have removed it from the back box and allowed it to dangle down the wall away from the metal back box. I have turned off all WiFi. I have turned off the NEOHUB so the mesh network is not in force. I bought ferrite beads to put round the CAT 6 cable at both ends and it made no difference. I am contemplating re wiring a few (up stairs is do-able but downstairs will be next to impossible!) It is currently wired with CAT 6 UTP Heatmiser technical support were of the mindset that it was to do with sudden humidity change, but in a bedroom in the middle of the night any change in humidity is very gradual. Any help of advice would be much appreciated! Thanks

Is there any information on the 50/90 "issue" if the Sunamp unit is connected to the grid only without PV (ie. charging it during economy 7 period)?

I would be interested in the results of your energy usage when you have them @JSHarris I am thinking of a similar setup @PeterStarck I cannot justify the capital outlay of PV at the moment. Did you oversize the UVC as you are only heating it to 45 degrees? Our SAP calculations shows our house will need the following... Water Heating Energy Requirements (kWh/year): 1,786 Space heating requirement (kWh/year): 12,984.35 I believe the water heating requirements are massively under estimated as at the moment we use 2 showers and some hand washing per day and a few baths each week, but with two young kids the hot water demand will only grow so needs to be apexes for the future - I’m guessing maybe 200+ litres per day.

But even with a poor COP from the heat pump would it be more economical than using an immersion heater to charge the SunAmp? (Again buying the electricity straight off the grid)

Just to go back to what was said above - if the example @JSHarris used with a UniQ 9 or a 210L cylinder and both were charged using an immersion then they would both cost approximately the same to “charge” fully. But if the cylinder was “charged” using an ASHP then would the benefit of the c o p (even if it was poor) still be more cost effective than using an immersion. (For this example take that all electricity is being bought from the grid). So is the big benefit of a SunAmp the fact that is has such a low standing loss? Still just trying to get my head round the best DHW solution so apologies for the continued questions!

For DHW I have been advised if going for an ASHP to have a high gain heat pump cylinder but I am still interested in a SunAmp. Can someone please explain to me the heating costs, what I mean is..... a 12kw sunamp with a 3kw immersion will take a full 12kw of electricity to charge from cold. But if running a high gain cylinder then taking the c.o.p of the ASHP into consideration then to get 12kw of heat into your cylinder it will take half or a third of the required energy. I know @Nickfromwales has referenced SunAmps in the past so hopefully someone will be able to explain it.

So i am being convinced that an ASHP for the UFH and a SunAmp for the DHW might be a better solution, but it will depend on the outlay cost of buying these. I have been in touch with a few renewable companies and the cost of an ASHP is frightening, in fact their quotes have done a very good job in nearly convincing me to go oil! Would anyone recommend somewhere to buy an ASHP monoblock 9kw or 12wk for about the cost of an oil boiler!? @Declan52 and @joe90 mentioned prices that seem a lot more appealing!!

The chat about ASHP and sunamp is interesting. I had originally looked at an ASHP but was convinced that unless putting PV on the house the cost of running it would be higher than buying oil needed to run an oil boiler. PV in my mind is out of the question as in NI there is no renewable incentive so the payback time is much longer and it is more capital outlay that I could do without. Can anyone give an indication on running costs without PV? Also, with the heat pump having to charge the sunamp will the c.o.p. reduction not cause it to become massively inefficient and expensive as you demand higher output temperatures from it?