Recent content by buggle52

Does anyone have any experience in trying to flush-mount a Vaillant thermostat control? I've got a VRT 392f (wireless one) and it's obvious it's designed to be surface mounted... but it sticks out from the wall so much! I can't help thinking it would look neater flush-mounted, with only the...

OK update. A Vaillant engineer came out and removed the flow restrictor. Now getting 13-14 l/min which I'm happy with. Thanks for all your help guys! For reference, the flow restrictor is in the cold water inlet monoblock (the one with the CH diverter valve) and sits behind the filter. btw...

Are you sure the flow restrictor is between the store and the heat exchanger? The schematic in the Spare Parts document (page 17) seems to show the "water quantity limitator" (presumably the same thing?) on the cold feed input just after the filter. After reading some other related topics on...

Sorry, perhaps I'm not explaining my thinking very well, or maybe I'm missing it completely. If the cold water is coming in at, say, 5c and I set the target temperature to <40c I would have thought I'd get the full advertised flow rate of 15l/min @ 35c rise. Is that right? I'm only getting...

I saw those figures, which is why I thought if I reduce the HW temperature to 35c and switch off the storage tanks I would see an improved flow rate. I was surprised to see the same 10-11 l/min.

I get that (the test). Just trying to keep theories and options open. The blender valve seems like a good option if there isn't any way to improve the flow, but at the same time I want to know if it's a boiler fault that can be fixed. I would never dream of calling out the plumber at the...

Interesting info about the flow restrictor, Alec. I'm sure they must have their reason for doing this... At least that explains why the storage tanks don't provide full flow. Presumably the flow restrictor only caps at the level the combi can provide at. If that's true, I don't understand why...

Lol! We're away this weekend so we'll let them off. ;-) But to be honest we do have a challenge... as far as the plumbers are concerned the pipes to and from the boiler are all fine (it's all new plumbing so I expect them to have confidence in their work) and so the issue is, in their...

Thanks Dan. I'll definitely be talking to the plumber next week about performing this test.

I actually had Three Valleys Water perform a measurement before I had the new supply pipe done. Here were the stats:- - 25 metres head / 2.5 bar at property - 40 l/min at the boundary - 4" cast iron water main on the road - 17m supply pipe (was lead, now 32mm) I haven't seen any results...

Thanks - that makes sense! I'll speak to the plumber about this. It might not explain why the boiler isn't functioning to the level advertised (IMO*), but it sounds like a pragmatic way of overcoming the issue. * I know this kind of comment could stir up arguments about dynamic pressure...

Forgive my ignorance; do you mean manually blending (i.e. using hot and cold taps) or is there a feature on the boiler that automatically blends 70c water to 40-45c? If there is, I couldn't find it on the controls (but they're not the most intuitive).

I agree, which is why I had a new 32mm water main installed (the flow rate on the old lead main was 14l/min), and have 22mm pipe from the stop valve to the boiler. The boiler itself only accepts 15mm so it's reduced just before.

Thanks Dan, I'll speak to the plumbers about your suggestion. Agile, the flow rate measurement certainly was open pipe, but I can't speak for how the pressure was taken. The boiler spec says it can operate at full capacity at 0.7 bar. Could there be such a big difference between static and...

Hi there, I've just had a Vaillant EcoTec 937 installed (the one with the storage tanks) and I'm not happy with the hot water flow rate. I'm wondering if anyone else has had similar concerns. The combi part is supposed to provide a max 15.2l/min at 35 degree rise (or 65 depending on which...