Independent Appraisal

Independently tested by Heating Ventilating & Plumbing Magazine (HVP)

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The difference between the Ravenheat and my old boiler is amazing. I get piping hot water in a couple of second, whereas before I had to wait a while. My radiators are now really hot when they used to be just warm. The digital clock timer which is built into the boiler itself is so much easier to use than the old one, which was a separate manual model. I can understand the timer and controls easily and make the boiler do what I want, whereas before it was just pot luck.

It looks very neat and compact on my kitchen wall and James did a good tidy job with the minimum of disruption, I also anticipate that my gas bill will come down because the condensing combi is more efficient and I can make it do what I want when I want.

Installing this model was a first for James, a sole contractor for British Gas in South London. It was replacing a long serving combi which had given up the ghost, providing heating and hot water to a two bedroom ground floor flat.

The old boiler

First impressions of the new Ravenheat Boiler were okay, a tidy, neat looking appliance. A quick initial look at the instructions to, as James put it:
"Make sure it doesn't say, don't do this whatever you do"
A guide pack and video had been received earlier, and these seemed straightforward enough, no nasty surprises.

The paper template for the new boiler.

Having ascertained that there was nothing unusual in the instructions, James positioned the paper template on the wall. This marks where the pipe connections go into the boiler, and is also used to mark the positioning of the flue terminal. It was also useful in positioning the boiler flush with the bottom of the kitchen units for a neat appearance.

None of the pipework connections which had fed into the bottom of the previous boiler were a match for the specified connections on the new unit, which involved some re-routing of pipework in a fairly confined space a little later. The old flue outlet was redundant, and James used the paper template to mark up the positioning of the new one.

There were difficulties here, due to an awkward angle and the positioning of a particularly bloody-minded chimney stack, although this was nothing to do with the boiler. An ordinary drill bit alongside a hammer and chisel were the tools used to make the new opening, rather than a core bit.

Another difficulty, again related to the environment around the boiler, rather than the unit itself, then arose. The wall on which the boiler was to be hung was, in James' evaluation, simply not strong enough. It had supported the previous boiler for a good many years, but, while it may have continued to do so for decades, could just have easily brought the whole edifice crashing down within minutes. It simply wasn't worth the risk.

The problem was eventually addressed with a combination of some 3/4" quality ply, the location of some studding in the wall, and heat resistant master board being affixed to the latter for a secure hanging. The boiler is attached to the wall (eventually in this case) quite simply with four screws.

The wall now strengthened with heat resistant motherboard

So once the house was fit to receive the boiler, how did the the installation progress ? In a very straightforward fashion, is the answer "Pretty good, pretty pleased" was James' summary.

As explained earlier, the pipework leading in to the old boiler made for less than straightforward connections to the new unit, but this did not present any undue problems. There was good access to the connections. With some boilers you end up getting cut to pieces when you stick your hand in there to make the final connections. On this one though I can't find a fault . Flue connections were straightforward, with the only problem being a fair amount of making good to do on the outside wall, both in blocking up the previous outlet and tidying up the new one. Any awkwardness with regard to this installation: "Had nothing to do with the boiler, just the way the house was thrown together".

 

The boiler in place prior to pipework connection

	All that hard work rewarded the boiler with system pipework connected up.

 

 

 

 

 

 

 

While there were no problems with installation caused by the boiler itself, a Ravenheat employee did take the trouble to telephone and offer assistance should any be required. Unnecessary in the end but a pleasant courtesy

As for the boilers technical specification, the nominal heat output is 81,200Btu/h, rising to 87,200Btu/h in condensing mode. Dry weight is 51kg and dhw flow rate is 9.8 litres/min at 35ºC temperature rise.
Clearances are 450mm(18") in front 125mm (5") above, 150mm (6") below and 5mm either side. Connections are 22mm for the central heating flow and return, 15mm for the dhw inlet and outlet, and 3/4" for the condensate drain.

The primary heat exchanger is copper, with a stainless steel plate heat exchanger for high heat transfer to domestic hot water and a condensing heat exchanger for high thermal transfer of flue gasses to water. Built in frost protection is a feature. It is of course a condensing combi, so a condensate pipe is necessary.

Verdict

Approval from both the installer and householder. Ravenheat as a company tends to pride itself on being installer friendly, and that appears to have been bourne out in this case despite a couple of awkward factors surrounding the installation.
An installer more accustomed to working on other brands encountered no difficulty on installing his first Ravenheat unit. A good result for the CSI 85 condensing combi.