– The building is a live Tax office and 15 floors tall, the project was done in the summer so we could fully isolate the Heating system without impacting on the staff members.
– The works were agreed to be done within normal working hours as long as the existing boilers were removed and the new boilers were delivered during a weekend.
-Gas isolation was also done on a weekend as the Domestic Hot water was fed from 2no Andrews Gas fired water heaters.
– The existing heating pumps showed signs of advanced corrosion, this was documented to the building maintenance team before works started.
– Water Validation samples were taken before works started, this showed inappropriate levels of inhibitor and debris which indicated internal corrosion.
-Before the works were started an intrusive asbestos survey was carried out, they paid specific attention to the gaskets within the existing flanges and the rope between the cast iron sections in the old boilers. They found Asbestos on the gaskets but not within the boilers. As such the scheme was adapted to eliminate the need to split any existing flanges. This however required welding being done onsite. This was carried out on a weekend with the fire alarm zoned off on floor 14.
– The boilers were able to be moved whole, they were transported from the plantroom via heavy duty dolly’s and taken downstairs via the lift (walls lined with purpose made quilting and the floor was covered with Corex floor protection)
– The boilers were disposed of via a metal recycling co, the waste transfer note was kept in the site file.
– The heating system is open vented, new valves including vent cocks were fitted.
– The headers were welded off-site in sections that could fit within the lift.
– The pipe work was bolted up, the screwed 50mm branches were connected to the boilers. The screwing machine was set up c/w an isolation zone to stop people coming into contact with a rotating pipe.
– Upon completion the pipes were filled to allow for a “working pressure” test
– The gas modifications were carried out by a Gas safe engineer, they purged the gas-line (gas – air) to allow for a new flange to be welded on. Once the new flange/valve was fitted the line was purged (air – gas) and the water heaters set back to work.
– The BMS was modified to allow for a 4-boiler sequence, a new gas solenoid & push button were fitted
– Once the pipe work had been tested then the thermal insulation was applied, 25mm rock wool type c/w Aluminium cladding.
– Inhibitor & Biocide was added by specialist (who also checked the chemical compatibility with the boilers)
– The flue works were done by the PC
– Ideal Standard commissioned the boilers