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IanR last won the day on August 16
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Ha - Not something I have direct experience of but I know of the "Probity in Planning" guidance document for councillors: https://www.local.gov.uk/sites/default/files/documents/34.2_Probity_in_Planning_04.pdf As per section 5 I believe the councillor in question would have to withdraw from the committee since if he's already given his view before committee he has a "closed mind" with regards the decision to be made.
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I'm going to ignore your comments now, no idea why you choose to be argumentative, some of your input is of value. The ASHP will be on and off, the emitters are more constant. They are not balanced.
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The gauge in the pocket 2/3 up looks close to me measuring at 35°C, although both the gauge and the laser temp gun will likely have a ±1°C tolerance so can't be relied on to compare between the two. You'll need to measure a few times to get a feel for what is going on, the temps are dynamic as the ASHP comes on and off and you're wanting 0.1° accuracy which isn't achievable with consumer devices. It would be nicer to see the temps across the top, and those at the bottom within 1° of each other. If after multiple readings, at different times, you are still seeing a similar result are you could try to slow the emitter pump down and are you able to limit the flow rate of the ASHP? Not sure if it's a setting available on all HPs, but I can turn mine down (on space heating only) to make it run slower for longer. I set mine up with a data logger and DS18B20 sensors and some times the traces would show the flow temp to the emitters higher than the flow from the ASHP, which isn't possible - the accuracy of the readings I need are not within the capability of the DS18B20's. After about 10 different sets of readings, each running for a couple of hours mine averaged out with the emitter side being within 0.5°C of the ASHP, except just as the ASHP stopped or started. Is it cold enough that the emitter circuit is running continuously (my own heating isn't on yet), are the measurements you have taken are at a reasonably steady state?
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? The emitters are not on, the Buffer is at flow temp, possibly fully charged. You can't draw any conclusions, unless you have a biased view. A 4P buffer removes the inefficiencies and warranty concerns of short cycling, at the cost of minor standing losses and powering a second circulation pump that would not otherwise be required in most cases. ? The ASHP will switch off when the buffer is fully charged at flow temp.
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That's not correct. A 4P buffer is to allow hydraulic separation, allowing the emitter circuit to take energy at a different/slower rate than the ASHP adds energy, reducing short cycling. Thermocline/stratification is a robust phenomena that does not require balanced flow rates - it occurs in HWCs that do not have balanced flow rates, and have no baffles or features to promote stratification.
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You'll be losing a lot of temp from the uninsulated pipe work. Can you measure the temp on the pipe into the buffer from the ASHP, just at the joint to the tank.
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Keep an eye on the temp gauge, there's no circumstance where it should stay at 30°C. At 2/3 up the tank then when the ASHP is on it should mostly be showing a temp around the flow temp, and when the ASHP switches off, if the UFH is still running it will, after a while, drop to return temp, shortly before the ASHP switches back on. Flow temp is water temp coming away from the ASHP. The flow rates either side of the buffer do not need to balance, a 4 port buffer is there to allow the exact opposite, ie, the UFH to take energy from the buffer at a different rate to what the ASHP supplies it, it's what protects the system from short cycling. The biggest improvement you could make is some insulation on those pipes.
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It would mean 0.714m³/m².h, rather than ACH, natural ventilation. For total ventilation you'd then need to add the MVHR ventilation (converting your 0.5ACH to m³/h). Or you need to convert the air permeability target units to ACH and add to the 0.5 ACH of the MVHR. Apologies, I shouldn't have included the "@50PA" on the MVHR figure, it would be just the m³/h. The *10% is to account for the 90% heat recovery of a PH certified MVHR. If we're keeping everything in ACH, and the target is 2 ACH, then total house loses from air flow is the 0.2 ACH (from natural ventilation) + (0.5 ACH * 10% (from MVHR)). If the heating engineers don't consider MVHR then then I'd give them this value. [physical air permeability testing (blower door test) in the UK tends to provide results in the m³/m².h@50Pa units, as that's what building regs uses, so you need to work out how to convert between them and ACH for your property] I'd ignore natural ventilation for the MVHR figures. The building regs airflow requirements are a minimum, so base those on MVHR only. I'd only consider natural ventilation figure within the total house losses, when sizing the heating system.
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Is it a 4 port buffer? What size is it? What height is the temp sensor? Assuming 4 port (or 3 port) I'd go with flow temp control running off a weather compensation curve.
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It's actually 8m³/m².h@50Pa rather than ACH. Each house has a different relationship between the two so you'd need to calculate the ratio for your house. (PH is 0.6 ACH as you say) Supposedly, the Building Regs change due 2025 (if Labour continues with the plan) for the future homes standard will drop to 5m³/m².h@50Pa. 20 is used for an unexposed area, 14 tends to be used for an exposed area. I'd keep it, but use the "rule of 14". But, infiltration losses should be based upon: (air permeability (m³/m².h@50Pa) / 14) + (MVHR flow rate (m³/m².h@50Pa) * 10%) The higher insulation and air permeability you target the greater the proportion of losses due to thermal bridging. Have you attempted to account for thermal bridge losses for your construction type? Most heat loss calculators include a "standard" psi value for typical construction methods, if you are mitigating thermal bridges you should adjust for this.
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Barn conversion on five acre plot in Northamptonshire
IanR replied to Owain1602's topic in Introduce Yourself
Hello and welcome, Sounds like your LPA is taking a pragmatic approach, which is as much as you can hope for. Look forward to seeing your plans once you are ready to share. Hopefully keeping the portal frame has not put you off the passive slab, depending on finished floor level versus the height of the pads under the columns there's a bit of extra detailing to do, but it is all "doable". I worked through mine with Advanced Foundation Technology Ltd and came up with a neat solution dove tailing the two together so they have some previous experience which may be useful to you if you've not already settled on a supplier. Have you thought of construction method for the timber frame? While the existing portal frame is quite an open structure, keeping the purlings in place (to keep teh LPA happy that it's a conversion) does make it awkward to crane a panelised system into place. I settled on a stick built solution but went with an I-Joist structure to allow lots of insulation. Good luck with your planning app. -
Experience with EA for PTP permission to drain to culvert
IanR replied to Alan Ambrose's topic in Planning Permission
pre-2015 discharges have to abide by the "Rules that apply to all discharges" section of the General Binding Rules. When you say "OK treatment plants", if you mean a (BS EN 12566) small sewage treatment plant or a package treatment plant then they are meeting the requirements of the rules, but if they are still on a septic tank as most "1940 to 1960s" properties would have originally been, then they must upgrade or get a permit (which they are unlikely to get without changes). Under the General Binding Rules the must have a plan to upgrade within 12 months. -
Experience with EA for PTP permission to drain to culvert
IanR replied to Alan Ambrose's topic in Planning Permission
Nope, they'll assume you've gone through the rules and worked out you can't discharge under them. Yes, but... pre-2015 still have to follow the rules, which likely means having a plan to upgrade within 12 months. If they don't have a permit, then they are under the rules, if they're not discharging within the pre-2015 rules they're at risk of a prosecution, but in the context of your connection, they are discharging "within the rules". If your discharge would be wihtin 50m of one of your neighbours (that doesn't have a permit) then you can't discharge within the rules. (but you could have done pre-2013) If you can position your discharge 50m away from the closest neighbour's discharge, then you can discharge under the rules. -
Experience with EA for PTP permission to drain to culvert
IanR replied to Alan Ambrose's topic in Planning Permission
Does the Culvert have have water in it for most of the year? Do your neighbours have permits or are they using the General Binding Rules? Can you not discharge under the general binding rules or is there a neighbour within 50m of your discharge point already doing so?