I am probably on the wrong track here but couldnt you tee the 2 pipes for the priority hot water in to the primary flow and return and then just use a nc and no motorised valve to switch over when priority hot water is called?
There are multiple ways of directing the water but the boiler still requires a signal to tell it we have demand and this relay does that job full stop this can be configured with a modified s or y plan
@@andrewmillwardwatford9410 and I guess the relay is the only suitable method for doing 2 pipe on opentherm? Your videos are a great source of info by the way.
Yes indeed why fit one additional pump to the system when you can sell 4@£2000 a pop. It would be interesting to hear the customers feedback on running costs post the rejig.👍
I'm not sure why you've chosen Kelvin to calculate half of the temperature given in centigrade. Having said that the radiators could require more than half of the 74. Very often radiators on old systems need to run up to 50 degrees C but these have been upgraded and they're only in bedrooms so it's probably reasonable to expect temperatures up to about 40. ASDA job was never upgraded I can't tell you what the end design temperature for the radiators turned out to be
Cracking job Andrew. Looks like fun. You have given me an idea. I am building a summer house which will have a shower and kitchen. I was going to install a small electric unvented but might use the insulated pipe you have for the 25 metres from my 300litre unvented.
Andrew, this might be a daft question but I have the submount mixer on my 200W, the unmixed radiator circuit suffers from poor control and bedrooms too hot at night.setback. If I could rearrange the pipes on the submount to give me a second flow and return off the plate hx for a second mixed circuit, would it be necessary to retain a unmixed circuit off the boiler F&R?
It may be better to use the mixed circuit for the radiators underfloor heating. This is especially true if you still have room stats and actuators fitted to your underfloor heating system
So run the UFH on the unmixed circuit? How does that work when generally rads run at higher flow temps? Also when generally the boiler flow temp is set (differential) to give a higher temp than the mixed circuit?
@@SkellyMr a lot of the answers I need to give would end up in me writing a book. I encourage people to call me when an answer is potentially very long as a few minutes on a telephone call can transfer so much more information than text. If you Google my name you will get through to my company and they can put you in touch with me. But the basic principle is that the flow temperature required at the mixer for the underfloor heating is likely to be very close to the radiator flow temperature or higher. Also most underfloor heating systems are still being fitted with room thermostats and actuators. So underfloor heating fitted with actuators can tolerate a slightly higher flow temperature without any significant negative impact what radiators circuits are unlikely to be controlled in the same way. Although thermostatic radiator valves can be used to limit the maximum temperature of a room it is a pain to have to turn them down at night and up in the morning rather than to use the programmed profile on the boiler.
Have been using Viessmann now for a about 2 years - full range of boilers from 050/100/200 and now HP’s this year 2no ground source and 2 ASHP with 2 more in the pipeline - great products but you have to work hard to fully understand them Reason for the comment - I’ve always used their divicons never been brave enough to use separate pump & ebse mixers due to I might be longer wiring than plumbing - how about a video on the wiring or are you keeping that a trade secret 😉
The wiring of these is covered on a video I made a while ago. The wiring process is exceptionally easy so next time save yourself a fortune and try it with the esbe mixers
@@andrewmillwardwatford9410 Thanks I shall have a delve into your past 😂 but to be fair I’m subscribed and thought I’d watched most of what you’d put out Keep it up great content 👍
Hi andrew.. sorry if i sound stupid here. You have 3 pumps running off the close coupled tee. Would they not be fighting against each other? Is it more beneficial with 3 individual pumps on each circuit rather than 1 decent sized pump? Love the videos! Very intresting stuff.
Yes so much of the Returns to prevent backflow in case of any pump being inactive. Interestingly on the pre-built pumping stations the non-return valve is on the return on the secondary side, I can't see the point in this but on the vaisman schematic it is clearly showing in the position I have placed it in this job. I have on different jobs placed non-return valves in different locations and I'm not sure if I've got this correct every time
I've not seen any love a viessmann more than you. Wowser, what a long term relationship. Anniversary must be coming up. Thanks for sharing your work for us to learn and enjoy
@@andrewmillwardwatford9410 the main exposure I've had with these boilers was years ago when a viessmann evangelist in Watford told me about them. The man would not install anything other than a viessmann. I reckon he has shares in the company and if not should have. Since then I've probably seen no more than 10. I've seen 3-5 in commercial settings. Vitodens 200w recently. I was quite impressed when technical support video called me. Never seen that before. I don't think Andrewmann boilers haven't made much of a breakthrough in the commercial world as yet. Anyways I'm looking forward to hearing how this boiler beats others in hydraulic separation.
@@markfernandes2467 it's standard with the v200 and the v100 but you need to order the weather comp sensor as an extra component on the 100. The weather compensation sensor is about £30
@@andrewmillwardwatford9410 Thanks for the answer. :) If you weren't in Watford, I'd try to ask you to fit my boiler, great knowledge in the video. Along with Symon (Urbanplumbers), you two are the best on YT & about the only ones I trust. Getting "heating engineers" around & seeing them sneer when I ask stuff like "can you wire it though open-therm" or other such questions is really making things hard. as if they have that attitude, I have zero confidence in their abilities & they're not going to give any good advice for my install are they? Right now I'm struggling with boiler choice. U & Symon seem to disagree on Viesmann (except W200) For combi I'm thinking Veismann W100 B1KF-30kw or Vaillant EcoTec plus 826 (the new one) this is for a 2 bed 3rd floor (top) flat 72m2 currently 1 bath 16l per min mains flow currently reg boiler fitted with 117 unvented cylinder, heat loss here is maybe 7kw. (self estimated with an online tool) I'm also thinking if I should change the location from Kitchen, to behind a stud partition in the WC (currently dead space) re routing Gas & Mains water to there as I have access to the loft and the flue would be easier on that elevation, as the building has an adjoining flat roof with access under that location at the second-floor level, so my flat is like a 1st floor flat on that elevation only. To the front, it's 3rd & the new flue (needed) can only be fitted from the inside (push-pull & snug) Anyway, on the boiler chioce, which would you go for ? the W100-30 or the 826 "remastered"? If remastered I hear I should always fit Vaillant controlls. Viesmann, not so sure, maybe 3rd party is ok? Would you go weather compesated & what controls?? Any advice would be appreciated Andrew, cheers & keep the vids coming. Hope you do a collab with Symon one day
Confusion haha that the word I am after Heat Pumps hide behind confusion.How do you control Flow Rate it is a mechanical valve set and forget pumps have 3 speeds that is not volume litres per minute is a variable depending on outside temperature is it not.Said wee Jimmy at the back of the class.I am passing the time trying to figure it out.Cheers good content can’t keep them all Happy haha.We don’t all have money to throw at it you must have a cheap pump .your installer was crap,your low loss calculations are wrong take your pick they all apply.
Each room in a property will have a different requirement for heat input. We need to establish the correct pipe spacings for each room based on the same flow temperature. This may require 100 ml spacings in one room and 300 ml spacings in another
I think a lot of people have had them poorly installed and those people live in regret. However this is no different to gas boilers that are poorly installed it seems that using a heat geek is a fairly good guarantee of ensuring you get a good installation
The customer will be really chuffed with this new transplant, much easier to control. Why have you got flow control valves on the cylinders? Does Viessman not have the native capability to control on two cylinders?
Oooo that’s another interesting project. I am surprised they needed to use the boilers - the multiple pumps churning the water up should have been able to heat the place.😉
Well originally I thought I was being smart and that by using an emp1 extension that I would get a hot water loading signal. Now I think I was wrong. I'm back on this job in 10 days time so I'm looking for a new strategy
@@andrewmillwardwatford9410 if you have to have the valves then i have a solution for you. What i would do is when the cylinder calls for heat, the valve activates a simple relay which makes the connection on the cylinder sensor. and when the valve is not power the relay reverts to its default position which goes through a resistor which tricks the boiler into thinking the hot water is satisfied.
do you have to have 2 port valves? i normally just wire the cylinder sensor through the overheat stat, so if it ever overheated (which it wont) it would disconnect the sensor which would stop the boiler from firing in hot water mode. heating would still work
@@cliveramsbotty6077 they are. Although at the moment I don't have the correct signal it is passing through the overhead stats. I have temperature control on both cylinders via cylinder sensors but I have linked both hydraulic lead to both boilers so there is some small discrepancy in temperature control. I need to find a solution for this problem in time for my return in 2 weeks time
I saw something like this install the other day on a home renovation channel, 2x70kw boilers for a 300sm solid stone building. I thought it looked overkill, what do you think? ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-AsupnUQt4U4.html
This is more often than not the fault/intention of the M&E specifier. The more complex the design, the higher the value of their bill. They know it's oversized but also know the client hasn't got a clue what the requirements are so they just design away and invoice accordingly. Then we come along and are told to stick the the design and just install what's been specified. Plenty of rogue traders in the supposed professional industry... Thorough video as always Andrew, thank you.
Thanks for the video. I have just installed a Viessmann 100-w and I am going to put weather comp in. It says in the manual that I should adjust it according to the property type but the graphs are quite hard to understand.
Very interesting video. The secondary pumps that do this are Magna 3 set to DT control. You need to add a sensor to use this control mode. They are also very useful in more complex systems with plc or ddc control with cim module they play nicely with supervisory control. So you can set limits on low speed / high speed and use DT control in between. Downside is expensive and time consuming to setup!
I fitted one about a year or so ago on DT control. But what we need on heat pumps is to a very the flow according to the cycle. This way we can minimise negative mixing until it is needed to prevent cycling auto charge the buffer prior to defrost
Sounds like a major simplification and improvement planned. Personally I would want to retain a low loss header as planned with the viessman header but configure system to keep the 3 port mixer for ufh. Fit smaller correctly sized circs.. I would do this so I have redundancy if one boiler fails. So either boiler can provide for any demand. Ufh, rads or dhw. Interesting video, thanks for sharing.
I've seen plant rooms in palaces and can tell you for free that this looks better. Guess they are trying to make money off the material mark up. Go on Andrew, get those robbers b4 it's too late😮
Totally agree. Most m&e consultants just copy & paste from other tenders. Seen it so many times. But over-engineering & over-specifying also happens domestically. We see a lot of the blue van brigade quoting to putting 30kw heat only boilers when we do a full house heat loss survey that comes to about 16-18kw. Crazy
Hi Andrew, is there any advantage or disadvantage of forming the CCT in 35mm, followed by 35mm upstream and downstream of CCT, down to 22mm to go through the filter and air separator and connect to boiler? Or just run the whole loop in 22mm?
@@aliatas6647 sorry I just reply to you thinking I was replying on a Facebook post. Yes there are rules for distances from elbows I think if you Google close coupled Tees you'll find the images you may have to Google closely space Tees
@@andrewmillwardwatford9410 thanks Andrew. Can you feed multiple secondaries of the single CCT from the primary loop? Or do you need to have multiple CCTs feeding each zone separately? I only ask after googling this stuff and would be great to know you're experience of it.
@@aliatas6647 I'm afraid none of your questions have very straightforward simple answers. You can have both but having multiple close couple teas suitable for use with weather compensation so it's not something that I would recommend other than if you're trying to fix an old system has no real weather compensation option
