The old Potterton Netaheat had failed and had been sited in a very rough fashion halfway down some cellar steps.
The hot water cylinder was located above the cellar on a raised floor, which would have been the first landing of the stairs in the Victorian property’s original layout.
Sited in Caterham, Surrey, it would be fair to say that the heating system had been bodged up by the previous owner, along with the electrical work. Various leaking parts had seen the attention of a silicon mastic gun, including radiator valves.
Our customer rather liked the idea of fitting a new bathroom in the area previously occupied by the hot water cylinder, and this meant lowering the floor, which from our perspective meant;
– a combination boiler
– relocation into the cellar for all the boiler plant
The problem with locating the boiler in the cellar is getting the flue out, and dealing with the boiler expansion relief and condensate water. There is a boiler available in the UK which has some very flexible flue arrangements which would seem ideal for this application called a Keston, but for reasons we’d rather not go into in this public forum, they are never specified by ‘Hot Water & Central Heating’.
We fitted a Vaillant ecoTEC 837 in the cellar, and used a void area to run the flue to a suitable height for a horizontal discharge. Gas Safe Register are quite rightly insisting that flues in voids must be able to be visually inspected and suitable arrangements are in place.
The condensate and high temperature emergency discharge from the boiler were handled by a new condensate lifter product specially designed to accept high temperature water, this is unique we believe. We no longer fit the Vaillant branded condensate lifter because Vaillant UK exclude it from their extended boiler warranty.
A Mainsboost GC450 accumulator was also fitted in the cellar to boost the water flow rate and separate the water supply, as the other 5 flats in the building cause water starvation issues as they are all fed from the same rusty water main around 200 metres long. The water main here was delivering a very high static pressure, peaks of around 7bar were measured. A pressure reducing valve was fitted to protect the appliances and provide a uniform performance via the acumulator.
The boiler exhaust was fitted with a Vaillant plume management kit, in white to match the building, as cars often part in the vicinity of the flue outlet, and the mildly acidic condensation could cause damage to paintwork.