Search results

Thanks @Mottie. Do you recall what issue you had before you changed d.00 ? Since my boiler is a 30kW boiler, I assume I would change d.00 to 30? What difference can I expect?

Thanks @CBW but don’t believe the boiler is undersized. However, if it was, why would it cause the problem I am seeing?

I recently had a new 2023 Vaillant ecoTec plus 630 (30kW) system boiler installed along with a Low Loss Header (LLH) in my house. I have 21 rads in the house and a room with UFH. The LLH was introduced as I was finding (before the LLH was fitted) that my old boiler (Vaillant heat-only boiler)...

I am looking to replace my existing Vaillant heat-only boiler with a new Vaillant ecotec plus 630 system boiler (30kW). I have a megaflo hot-water cylinder, a central heating system (serving 21 radiators) and an orangery built last year (6m x 4m) with underfloor heating. Through running some...

hi @Milleniumaire, at the end, the UFH manifold was installed on the ground floor next to the orangery that got built. The pipework from the manifold runs up along a wall in a room on the groundfloor (pipes are boxed in so looks fine), under the floorboards in the bedroom & hallway above, and...

thanks @Harry Bloomfield. Yes, I got the feeling that these Vaillant controls should be considered as a method to improve the operation of the boiler, and hopefully improve the comfort level within the house. Which boiler did you have installed? Did you deliberately wait to get the Vaillant...

I am considering replacing my existing boiler with the new 2023 Vaillant ecotec plus 625 boiler. I currently have 3 x Heatmiser neoStat thermostats that are all hard wired back to the wiring centre; one for the central heating, one for a room with UFH, and one for the HW. I use the Heatmiser...

@Johntheo5 - just to run some further tests, I reduced the speed of the main pump to speed (1) from speed (3) (photo attached) and took the following readings with just the UFH on.

@Johntheo5 - I decided to run a fresh test today and the readings are shown below. The boiler temp is set at 65 degrees. When the UFH is off, the flow meters are 0 so I must have taken a wrong reading yesterday. Also, on T+40, the flow temp on UFH was either 40 or 50. I wrote down 50 at the time...

@Johntheo5 - one thing I forgot to mention, I did share the above readings & observations to another person and their response was: Simple - fix a 2 port buffer of around 25 to 50 L capacity (closer to 50L is better), across the flow and return loop to the boiler or across the flow and return...

@Johntheo5 - I took some readings of both, the boiler and UFH. The readings are shown below (I also attached a file showing these readings incase the image below did not come through). I took the readings across 5 minute intervals. What I found is that when I had both, CH and UFH turned on...

thanks @Johntheo5. I have attached a photo (taken last October) of my UFH system. As requested, I will take a reading of the flow meters along with the two temperature readings once the system (both, central heating and UFH are both on) is on for 15-20 minutes. The blending valve temperature...

thanks @Johntheo5 - TBH, I am no really sure how to go about measuring the flowrates through the tubes and the manifold dTs :(. I do not have any design details of the UFH set up. I did call the Vaillant technical team and they mentioned that the reason my boiler is cycling is because the flow...

no, I didn't try it on my own but I did get another heating engineer who came over last week to carry out a heat loss calculation from which I should get the results any time soon. From the two heat loss calculations that have been carried out, British Gas only took measurements internally of...

I am just waiting for a heating engineer to come round next week to investigate further on the boiler cycling and boiler options / low loss header. Since yesterday, I could hear my boiler making a strange sound and coincidentally, whilst British Gas were over to carry out their annual boiler...

Thanks @Johntheo5. Do you think the introduction of a buffer cylinder on the return of the CH circuit will resolve the problem? The Viessman Vitodens 200W you are suggesting is a system boiler from what I can gather and will have its own internal pump. Would that mean I would need to get rid of...

The work was carried out by the builder’s heating engineer so no design work was carried out

Thanks @Johntheo5. I’m not quite sure what to do next to rectify the issue?

@ScotchGas, @Johntheo5, @ianmcd - I was in discussion with another heating engineer around the issue I have where my existing boiler continuously short cycles when I just have the UFH on. I was under the impression this was done to an issue with the boiler. His response was that the boiler isn't...

@ScottishGasMan - having had a few heating engineers over, it has been established that a Vaillant ecoTec plus 430 is the right sized boiler for my home. I am about to give the nod to one of the heating engineers to carry out the work as they seemed the most knowledgeable, local, good reviews...