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osmononame's Achievements


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  1. Hi all, I thought i would update this thread as this saga with my hot water has continued to run and run (or run out as is normally the case)! The installer came out and installed a NRV between the bronze pump and the tank - that solved the lack of hot water when the pump was switched off but I am still losing a whole lot of heat through the tank and it can go from full hot to room temperature overnight. the plumber was out a few times and couldn't see anything wrong and I have lived with it until last night when I wanted a bath and what do you know! No hot water despite us being out of the house all day!! I have the bronze pump on a smart plug and so its only on when motion is detected in the landing - so most of the time this pump is actually off and so i shouldn't be losing any heat through the secondary return. I ended up checking the piping myself last night and on the SC300 manual for the secondary return should be connected via the expansion vessel connection and the combination valve but my secondary return seems to be plumbed into the balanced cold water connection. Could this be causing my issue? To my layman's eyes where the connection is supposed to go and where it does go on the combination valve are not miles apart but surely this can't be right? The plumber has said it doesn't make a different and OSO technical hasn't responded to me. Can anyone chime in while i wait for OSO?
  2. Hi all, We are in the process of deciding what to do with the raised deck in our back garden - work probably wont begin for another few months but with the way things are going it's probably best to get everything arranged now! We have a suspended beam and block outdoor deck - it will be screeded and then will have some EPDM to seal it for the rooms beneath. The original plan was then 10mm rubber spacers and regular paving but having been to a few landscaping places we quite like tyhe look of the epoxy pebble (epoxy bound maybe?) systems some of them do. We are quite tight for margins at the thresholds to our doors and they werent sure at the showroom how thin it could be laid (best to ask the fitter they said!). Does anyone know? and if so, provided it's only going to be light pedestrian traffic, it should last ok? We can probably manage 30mm but anything more and it might be a struggle. Can it even be laid over EPDM as that will be a deal breaker if it can't or we would need to find another solution to waterproof. I have tried checking online and the only times i have seen the thickness mentioned is when talking about parking cars on it (which wont be an issue in a back garden!). Anyone done anything similar / any tips/hints would be appreciated!
  3. I ended up going with a manifold on each floor. I still think from SF going to FF would have worked but wasn't brave enough to make that leap! I am running the Salus self balancing actuators and the pumps at the manifold on their slowest settings (so there would have been some margin had I put everything on the SF). In hindsight I would probably skip the ufh in the SF altogether as it's simply not been cold enough to need it on. Even now with minus temp outside the study on the SF is showing 23 deg C (it's set to 16 deg). P.s. I am not sure who is designing your system but ours was overcomplicated with certain/most rooms needing two runs due to the length of the runs but once we got started I decided on one longer run per room but switched to the self balancing actuators (I had to go to another supplier as the one that designed the system didn't do the self balancing ones) and it's worked well with no issues.
  4. Thanks Peter. The uvc is a OSO Super Coil - so preplumbed for secondary return / system boiler (which we have) and the secondary return looks to be where it should be per OSO manual (via the expansion relief valve). However even the manual says to install a NRV - I have ordered one now so will try that and and take things from there.
  5. Good evening all, Quick question about a secondary return pump - i have one in my house and my plan was to switch it off at night so that the hot water is not continually circulating at night. I have put it on a timer but what I am finding is that when it is switched off I don’t get any hot water! Maybe its a bit tepid but certainly not hot - as soon as I switch the pump back on I get the hot water returning! A couple of things to add if it might help diagnose: 1.Our first pump failed, and we ran the system with the pump disconnected (so turned off at the valves on both ends of the pump) and it worked fine and we got our hot water albeit having to wait 30/40 seconds for the hot water to reach us and 2. When the pump is switched off the brass fittings on both ends of the pump are COLD to touch - almost as if ice cold water has been running through them - could anything obvious be causing this? Surely i should get hot water when the pump is switched off? What could be causing presumably cold water to be running through the pipes when the pump is switched off? p.s. After a bit of googling it seems that I need a non return valve between the pump and uvc - can't see one on the system so hopefully thats it but if anyone can corrobate that would put my mind at ease.
  6. From memory about 50mm but would need to check with the structural engineer - we are really tight with the threshold at the sliding doors so dont think we can go much thicker than that.
  7. and yes we are using 7n blocks - thats what the structural engineer specified - although the brickies were moaning about the variances in the block sizes - apparently the manufacturer (Patersons) are bad for that!
  8. Thats correct and yes its been grouted with a sand and cement mix. We just grouted these parts with the same sand and cement mix - should I remove/replace with concrete? I guess now is the time to do it if it will help!
  9. Yeah we did that. Our beams are doubled in places and also blocks sideway in places. We could have gone for shorter runs and had less bounce (and a compromised room underneath) that way but as things always end up at - budget - decided our fate and we ended up with what we could afford. Not unhappy with it and I knew to expect it - just an observation. Maybe with the screed it'll settle a bit too.
  10. Thanks for that - we did think it was due to damage when handling the blocks but we have had broken blocks now from 3 separate deliveries and handled them like a newborn when installing them after the first crack but who knows how they were handled before they got to us! There is going to be a storage room underneath and the fear is that a block comes crashing down on your head years down the line - good to know the screed will strengthen everything! On another note the bounce is terrible! I can tolerate it outside but if we had gone for beam and block internally I think I would have been sorely disappointed. Had it not been for access issues I would have probably gone for something like a hollowcore floor.
  11. Hi all, So due to the height at the rear of our house instead of going for a traditional timber or composite decking area we went for beam and block flooring which would hopefully give us some longevity. The issue we are having is that about 3 of the blocks have broken with light foot traffic already (only installed last week). Surely this isn't normal and you should be able to walk on them without fear of the blocks cracking? I'm waiting on the structural engineer calling me back but it's a but unnerving hence me posting it here.
  12. Good evening all, I don't suppose anyone has set one of these up on their own before? I've just turned mine on and before I am able to set it up it's asking for a password - I've checked online and can't see anything useful. I will call Zehnder on Monday but was hoping to get this unit set up this week. Ps I have checked the manual which says that your installer will know but it's no good if I'm self installing! Thanks in advance.
  13. That's already done. I got a roll of their cable off eBay just so I could run it into the house from the main street (and also have provision for it running into the garage if they decide they don't like the one I have run as I don't want to be drilling holes into the house). Literally they need to turn up and connect it in. Hopefully my house will go onto the RM website soon and I will try them again.
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