Pre-plumbed cylinders are usually the choice for new build where they have plenty of people to move the units into the airing cupboards before fitting the doors but I like the look of them and I had already decided that on my next cylinder installation I was going to try a pre-plumbed unit. It isn’t that I find it difficult to plumb up an unvented cylinder but when you start adding up the cost of all the controls and zone valves the material costs are surprisingly similar between the package deal and the plumb-it-yourself option. The thing that really persuaded me was that we had one week to install a new boiler and cylinder, take out the old ones, strip out all the rads and put underfloor heating in the entire ground floor. The considerate customers had gone skiing giving us an empty house but it was made clear to me that if it wasn’t all up and running by the time they got back on Saturday I would be putting them up in a local hotel and there was no way I was going to do that because there ain’t no cheap hotels in London.
I took delivery of the Kingspan Tribune Xe Direct Cylinder and Worcester CDi Classic system boiler the week before we started. I had measured the loft hatch and knew we would have to remove the loft ladder and take out the stop beads to get the cylinder up through the hatch. It went, just, and there were no scratches on that lovely white casing.
A full up 210-litre cylinder weighs something like 230 kilos so we had to make sure it was positioned over an internal wall. We built a stud wall next to it for the boiler so we had a nice short run for the flow and return.
The architect specified a Vailant but I changed it to a Worcester CDi Classic system boiler because I believe it is the most reliable boiler out there. You can argue with me if you want. It was only when I came to do the installation that I realised that there was a circulating pump and expansion vessel supplied with the cylinder that would not now be required. I could either have ordered the cylinder without the pump and expansion vessel or gone for a heat only boiler. As it was we had an extra pump and expansion vessel. I was happy enough about the extra expansion capacity because the underfloor heating circuits pushed the water content up to the limit of the boiler expansion.
The great thing for me and my mate Steve was that the zone valves were pre-wired and ready to hook up to the ground floor and first floor. Kingspan also supplied a programmable stat. for one floor and a programmer with a heat sensor for the other floor. This would allow us to control the DHW from the programmer. All we had to do was connect the primaries, the cold supply and the hot water outlet and the pressure relief pipe to the tundish.
There is always a trade-off between the amount of insulation you put around a cylinder and the size. If you go too far you won’t be able to fit it in an airing cupboard. The architect had specified a 210 cylinder but if we had gone for a slightly smaller capacity we could have had an A-rated cylinder and relied on the 30kw boiler to provide a rapid recovery. That would have been my preference because you can even order a CDI with an internal diverter valve to prioritise the DHW. That said, Kingspan has managed to reduce the heat loss of the cylinder by an impressive degree by using a side tapping for the hot water outlet and incorporating an internal air bubble for expansion plus a whole load of other little tweaks. The lack of a top tapping means that the top of the cylinder is fully encapsulated and there is no convection up through the outlet.
Every plumber knows that not everything goes well but on this job, we were blessed and it went like a dream. We started on Monday morning and did civilised days and by Thursday afternoon we were filling up. There were no leaks or dramas which was amazing because I had somehow managed to leave out one olive on the underfloor manifold. It didn’t leak and it only came to light the next day because we had one olive left over in the fittings bag.
So the customers came home to a warm house and hot water pressure that more than matched that in their ski chalet. Given the fact that we removed a 30-year-old floor standing conventionally flued boiler that was working on gravity primaries to an unlagged copper cylinder we were fairly confident that their gas bills were going to be halved. To help things even more we had installed 80 mm of Kingspan insulation in between the ground floor joist and laid the underfloor heating which was set to run at 50 centigrade to give a nice low temperature even heat. That said I still have some reservations about putting cylinders in ventilated roof spaces even if they are very well insulated cylinders and so I have recommended that they build an enclosure from insulation board to reduce the heat losses even further. All those little improvements add up to a lot and that really is the philosophy behind the development of the Kingspan Tribune Xe Direct Cylinder.
Kingspan Tribune Xe Direct Cylinder
- Up to 45% extra insulation for reduced heat loss Built-in thermal expansion spaces eliminating the need for an expansion vessel
- Designed for use with 3kW immersion heater – can be used alongside ‘low tariff electricity’
- Suitable for all-electric buildings off mains gas supply
- Duplex stainless steel for ultimate peace of mind
- Suitable for fully pumped circulation and sealed primary systems. Not suitable for gravity circulation
- Wide range of capacities – from 120 to 300 litres
- Low running costs
- 25-year guarantee on basic vessel and 2-years on components, subject to T&C’s
*T&Cs apply 25-year guarantee on basic vessel and 2-years – See more at: www.kingspanenviro.com.