New Gas Boiler

[John Rumm]

Although even the SS ones can fail as I discovered:

(still pleased with the boiler though, and it was quite an easy fix!)

[John Rumm]

FWIW, the boiler has a dedicated input for the NTC on a cylinder (contrary to my expectations it does not actually use the VR6x or eBus for that bit of communication - it needs a dedicated wire between the NTC on the cylinder and the boiler.

(as I discovered when I looked at the wiring diagram to work out where to connect the NTC on the cylinder to the VR61 which were right next to each other, and ended up having to pull in a new wire along half the house!)

[SteveW]

The VR65 and VR66 do have the NTC input on-board and use the ebus to communicate the temperature to the boiler.

[John Rumm]

ok that is better then - I was surprised that it was not like that on the 61 to be fair. (also the unistor did not come with the connector that would mate with the one on the end of the loom for the Tank NTC in the boiler - so I cut that off in the boiler and used a couple of jelly crimps instead)

I have a feeling that the 65 was available at the time, but did not support two heating zones as well as a DHW one (i.e. control of 3 two port valves)

[SteveW]

I think that you are right.

The VR66 does support two CH zones plus the DHW and has a switch to make it behave like the VR65 if it is being used as a direct replacement.

[R D S]

What are you using? I've got Conrad ones with the motorised valve replacing the TRV, a couple have failed and i'd like to replace them with something better looking and possibly quieter.

[SteveW]

Mine have been in for about 18 years now.

For some unknown reason, B&Q were having a clear-out of standard Honeywell 22mm motorised valves, so I managed to get them for £18 each and Maplin were selling combined timer/thermostats for £14 each.

Looks are not a problem, as 5 valves are installed in the airing cupboard (for bathroom, hot-water cylinder and 3 bedrooms), 3 valves under the floor downstairs (for hall, kitchen and through living-room, plus a further valve in a cupboard in the conservatory for the under-floor heating there.

There are two boxes with transformers and relays, as the battery powered timer/thermostats switch 12V ac, while the valves are 240V ac. The reason for doing it that way was that I could install using alarm cable, up the edges of door frames and only make a new chase as each room became due for redecoration - plus I could have one in the bathroom.

[Theo]

I'd quite like to do a setup like that, ie an insulated pipe run to each rad going back to a central point, where all the valves are located.

I had a look and I think it might be doable with an UFH manifold and UFH actuators, but they're typically flow restricted to 5 litres/min - might be OK for UFH with a long pipe run, but perhaps limiting to a rad which has a smaller area.

I think the pipework on the manifolds has standard screw threads so it might be feasible to remove the flow restrictor and fit a conventional tap-style valve (which you can adjust for balancing). I'm currently on the lookout for a cheap enough scrap manifold to experiment.

Theo

[SteveW]

Yes. Even older, basic systems were similar, often with a pair of manifolds downstairs and a pair upstairs, with all of the the radiators piped back to those manifolds.

In my case though, I had to re-pipe the radiator feeds to the two locations, as the existing pipework (from before I bought the house) was piped with runs of 22mm pipe, with individual, local tees, for each connection.

That may well be enough (especially if you have oversized radiators). There are online calculators that let you input supply and return water temperatures, radiator output and room temperature, to calculate the required flow.

[Andrew]

With EDF perhaps, but not Octopus. The last time I looked into the latters tariffs and queried this their reply was 'we don't care what you use the cheap hours for'.

[Theo]

Octopus Go now needs an EV:

"2. Have an electric car and a home EV charger

Our Octopus Go Tariff is designed for customers who either own or long-term lease a battery electric vehicle or a plug-in hybrid vehicle that they'll be charging at home, so you need one to join. If you're in the process of getting one and have an order number to hand, we can switch you so that you're ready to charge once your vehicle arrives."

https://octopus.energy/go/

[Robert]

[Tim+]

We had that before the cost spiralled and moved over to Go. That said, prices are looking more tempting again. They were paying for you to use power for a while yesterday I believe.

Tim