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Everything posted by JohnMo
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Looks like the party is over....
JohnMo replied to Beelbeebub's topic in Air Source Heat Pumps (ASHP)
How? -
Looks like the party is over....
JohnMo replied to Beelbeebub's topic in Air Source Heat Pumps (ASHP)
Gee, the discussion above in this thread says the normal consumer has little or idea of any technical aspects of a heating system. So why would you want to give them something to fiddle with, which will ultimately end with no heating being available, when they get it wrong. And an expensive bill to return everything back to working again. The normal person or indeed most people, want, a single box on the wall that says hotter or colder the heat pump then runs at lowest cost to achieve this in a suitable timeframe. Don't all heat pumps (except Vaillant and couple of others) use modbus anyway. Which is pretty much open source once you map the addresses. -
Most cylinders aren't much better that C. You can get A rated ones, but the cost premium is huge. So why bother? If keeping water a 50 degs or lower the losses are pretty small anyway. You are likely to loose way more heat by poor pipe install/insulation (or lack of) and not providing thermal current stops by correct pipe orientation.
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For all networks, EE, Vodafone/Three and O2. We get ok Vodafone, everything else is a zero for coverage.
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Turn on your problem radiators and make sure they have no air trapped - so bleed with TRV open. Can you force the radiator hot by closing off the other radiators via the TRVs? So the only flow is directed to the cold radiators? If not your may have bigger issues than simple balancing. Assuming they get hot, the system isn't blocked up. So now you have two options, pump set at too low a setting and not enough head to get to the issue radiator and/or balancing. dT that is big would indicate too little flow going through a particular radiator, low dT too much flow I would have a look at all the radiators to see what sort of dT is occurring across the radiators, they should be similar - do this with all TRVs open to get a sound starting point without adjusting anything.
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A lot of micro climates there, we are 6 miles from Elgin and the same from Lossiemouth, all 3 places can vary in temperatures by a couple of degrees. Or is it feast and famine, great one day rubbish the next.
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No as long as you can get up and into it's final position. Then insulate everything really well.
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Hybrid ASHP with oil fired boiler.
JohnMo replied to MichaelPD's topic in Air Source Heat Pumps (ASHP)
Suspect you have a couple of different issues. Radiator not heating sufficiently is likely radiator balancing issue. So more water going through the first radiators in the circuit and not making it the last one. So system needs to be balanced - or system needs a higher flow rate. A grant ASHP uses a flow setter valve maybe the plumber hasn't set this correctly. In the ASHP instructions it says how these are set up. Grant do stuff in a slightly strange way to make a plumber happy in most cases. So could be a wiring issue. I would make an effort to understand what is happening when the cylinder calls for heat and when it's up to temperature does it automatically switch back to heating. Find out what valves move or don't move at either end of the cycle. An easy way to do this is turn the cylinder thermostat down then select cylinder heating on the timer. On selection of heating via timer nothing should change, if it does you have a wiring issue. If central heating stays on all good. Then wind the thermostat up so you get a call for heat and see what moves and doesn't, then wind the thermostat down to put heat off does valves go back to original position. At this point the central heating should be back to normal - if it doesn't there is a wiring issue. When you DHW heating is that in hybrid or ASHP or oil boiler? -
Looks like the party is over....
JohnMo replied to Beelbeebub's topic in Air Source Heat Pumps (ASHP)
Or for manufacturers to sort it out so no one needs to mess with it. Atag boilers you just answer questions, and it selects the correct curve for you. So house type, heating type, insulation levels etc. Then you select up or down on the controller if you are not happy after a day or two and the curve is moved. Would say that is suitable for 99% of installs. -
Looks like the party is over....
JohnMo replied to Beelbeebub's topic in Air Source Heat Pumps (ASHP)
Other issue is these companies are all new start companies - will they be around in a few years? A car, you jump in heating is set to 20, system manages this with heating and cooling automatically. So there is nothing complex required to manage a simple curve. House too hot curve is lowered etc.. it should flip automatically between between heat and cool. I think Hitachi heat pumps do this already and have for years. -
some more reading FLY528GB_v2_display.pdf AIVC-2.pdf Construct-Ireland-February-2011-2.pdf
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Looks like the party is over....
JohnMo replied to Beelbeebub's topic in Air Source Heat Pumps (ASHP)
Se my above post -
Looks like the party is over....
JohnMo replied to Beelbeebub's topic in Air Source Heat Pumps (ASHP)
Sad reflection on the piss poor training we give to plumbers. Monkey see - monkey do, I am afraid. Good at pipe bending though. -
Looks like the party is over....
JohnMo replied to Beelbeebub's topic in Air Source Heat Pumps (ASHP)
If the contractor has done his heat loss calculation correctly he knows the what the WC curve will be. So only fine finding is needed. If he was smart he would enable the second set point within the controller, this is normally controlled by a volt free contact. Set the calculated curve and add an additional degree to secondary set point. Add a monitored thermostat. If the secondary set point ever is called for the curve is too low, if house is too hot curve needs trimming back. For the home owner they know no difference when second set point kicks in. House just stays stable. All contractors should be returning to ensure system is working as intended and make any necessary adjustments. But many never do. My old boiler has this ability and so does the heat pump. -
Looks like the party is over....
JohnMo replied to Beelbeebub's topic in Air Source Heat Pumps (ASHP)
Doesn't mean it's actually cheaper, which is the main point that people operate in that mode. The house gets damp they get black mould etc. Aren't you actually demonstrating the opposite running strategy, with a small tweak here and there you could be running WC. The main difference in short on/off operations is the fabric never stabilises, the high temperature heating causes drafts, people feel cold feet as cold air from top of room is pushed downwards. -
Looks like the party is over....
JohnMo replied to Beelbeebub's topic in Air Source Heat Pumps (ASHP)
So two situations heat pump and boiler, both have similar effects but way more pronounced with a heat pump. The lower the flow temperature the higher the CoP on a heat pump, and boiler the more condensing occurs so efficiency increases. WC flows the lowest possible temperature all the time so best efficiency all the time. -
Plaster-in valves
JohnMo replied to jayc89's topic in Mechanical Ventilation with Heat Recovery (MVHR)
I use cone filters in the extract terminals, you would be surprised how much stuff they keep out the ducts. -
Atamate_SDAR+Paper+2019+(1).pdf
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Looks like the party is over....
JohnMo replied to Beelbeebub's topic in Air Source Heat Pumps (ASHP)
It's all indicative of cheap energy, we had many decades of cheap energy - no one cared, the consumer accepted what they were given because that was the norm and NO ONE knew any different. The professionals should have, but they had inadequate training - trouble is most aren't knowledgeable now in low temperature systems. Training is poor, everyone is an engineer (unfortunately there aren't many Engineers). -
Looks like the party is over....
JohnMo replied to Beelbeebub's topic in Air Source Heat Pumps (ASHP)
And not be hot enough to heat the cylinder (assume not combi). But most people just believe if you only have heating on for short bursts it save money. Forgetting they have a boiler capable of 30+kW and it runs flat out for those short bursts. So 4hrs flat out, instead of 18 to 24 hrs ticking away. -
Help with leaking MDPE compression to water meter housing
JohnMo replied to NCXo82ike's topic in General Plumbing
See no mention of the pipe inserts, so did you have/install? A video of assembly easier than loads if words https://youtu.be/QDJ2gUNuf-Q?si=lF9exiA8-baO2cDL -
Install a pair of boilers and cylinders
JohnMo replied to allthatpebbledash's topic in Boilers & Hot Water Tanks
Or just fit a single one in a central location, or install in a remote location and have a timed secondary loop. If installing one get one with a large plate exchange and have better than combi performance for reheat - as I linked too further up thread. -
Possibly, one the kids or partner closes them, are you going to go round checking they have been opened again, every day? Most likely not.
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If it has an immersion that isn't being controlled by the heat pump, it will be compatible. If controlled by ASHP you may hit issues with the secondary cutout being bypassed. So may need a bit of rewiring to take away from heat pump. Be careful with those numbers that may be case in a hot country, which the UK isn't. Your maybe nearer say 1 or 2%
