COMMERCIAL REPORT / STOCK CONDITION SURVEY. Sydenham Hill Estate Sydenham Hill London SE 23

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1 COMMERCIAL REPORT / STOCK CONDITION SURVEY For Sydenham Hill Estate Sydenham Hill London SE 23 Submission Prepared by Gas Advisory Services Limited Date: 4 th June 2013 Gas Advisory Services Limited Phoenix House Slade Green Road Erith Kent DA8 2HY Telephone Fax gas@gasltd.co.uk Web-page: Safety Initiative Winner GB4894 Directors: V. Queen, R. Gonella. Registered in England No Registered Address: Phoenix House, Slade Green Road, Erith, Kent DA8 2HY

2 CONTENTS 1.0 INTRODUCTION 2.0 DETAILS FOR PROPERTY DATABASE 3.0 BACKGROUND 4.0 EXECUTIVE SUMMARY 5.0 CONDITION REPORT 6.0 RECOMMENDATION AND COSTINGS 7.0 PHOTOGRAPHS Gas Advisory Services Limited Page 1 of 14

3 1.0 INTRODUCTION This condition report has been commissioned by London Borough Southwark in order to obtain technical and strategic information on the existing district heating boiler plant and controls, This report describes the condition of the existing building services and makes recommendations for repairs and modifications that should be carried out in the near future in order to provide a safe and low maintenance building services system Survey of the building was carried out on the 4 th June 2013 The extent of the survey comprised of a visual inspection of the following systems:- Gas fired district-heating boiler system Hot water storage Calorifier s No tests or trials were conducted during the surveys and front covers, inspection chamber covers etc, were not removed to allow a more detailed condition assessment to be carried out. 2.0 DETAILS FOR PROPERTY DATABASE Sydenham Hill Estate Sydenham Hill London 3.0 BACKGROUND Sydenham Hill - district heating serves five brick built blocks of flats three and four storeys high built approximately 1970 The district heating is served from gas fired boilers within the lower ground boiler room located at Bromliegh Court; this also serves Thetford Court, Allebourgh Court, Dunton Court and Parfew All other blocks and maisonettes have their own gas fired individual system. Gas Advisory Services Limited Page 2 of 14

4 4.0 EXECUTIVE SUMMARY The level of servicing for the plant carried by the incumbent contractor is of a reasonable standard. Valves are easy to operate with no visual signs of leakage The heating boilers are operational but due to condition and age should be high priority to be replaced within 3-5 years with new high efficiency modulating condensing gas boilers complete with ancillary plant. Replace existing domestic hot water Calorifier s within the next 3-5years with high efficiency plate heat exchanger and buffer tanks It is understood from the incumbent contractor, that the heating provided within each dwelling only consist of 1 no radiator and a perimeter heating loop arrangement. This will only provide background heating, this is to be upgraded within the next 3-5years Recommendations and costing have been given in Section CONDITION REPORT Heating Boilers The district heating is served by two steel tube gas fired boilers as manufactured by Thomas Cochran Ltd There are no identification plates on the boilers showing outputs or year of manufacture. It is estimated they are in excess of 35 years old and would have an output of approximatley1200kw each. Both boilers were originally oil fired but converted to gas firing within the last 10 years. The boilers are manufactured from steel with water tube passes. Boilers manufactured from steel are vulnerable to corrosion on the water tube back plate due to condensation. Gas Advisory Services Limited Page 3 of 14

5 It was not possible to inspect the back plates as the boilers were in operation but external examination shows the start of corrosion on the base of boiler shell and around the drain cock area. See photo No 2-3 Both boilers have had replacement water tubes fitted due to leakage in the past and the left hand boiler was being re-commissioned during this survey following further replacement. This indicates these boilers are coming near to the end of their life expectancy. Boiler safety valves fitted to the boiler looked in reasonable condition but could find no calibration certificate. The boilers should be replaced with new gas fired fully modulating condensing boilers complete with break plates and filters within the next 3-5 years in order to maintain a continuous service throughout the estate. A thorough flue survey will be required before any work commences to ensure the integrity of the main brick stack prior the boiler replacement. Gas Burners Each boiler is fitted with a gas fired pressure burner as manufactured by Riello Type 822TI and has high and low fire facility. These burners are approximately 10 years old and spare parts will now become difficult to obtain. The general condition of both burners was satisfactory and operating correctly. The boilers were operational and the service contractor who was on site commissioning the left hand boiler following water tube replacement carried out efficiency test which show the boilers were running at 84%, efficient for this type of boiler and its age. This is a satisfactory result. (see below additional information) Gas Advisory Services Limited Page 4 of 14

6 Pressurisation Unit A pressurisation unit maintains the system pressure. There was no water meter fitted to record any water losses. This unit is approximately 12 month old and was operating correctly and in good condition. See photo 5 Pumps Currently there are three sets of pumps within the boiler house. Main heating pump working and standby belt driven as manufactured by Pullen Primary pumps serving hot water Calorifier s located in main boiler house. Secondary pumps working and standby belt driven serving hot water Calorifier s All pumps were operational some have had replacement motor and seal fitted due to age. These pumps appeared to have been maintained to a satisfactory standard but due to age should be replaced commensurate with the boilers with more efficient direct drive pumps. See photo 4 Chemical Dosing A chemical dosing pot device is fitted and water sample were last tested on the 01/02/13 and results were satisfactory. Controls The heating is operated by JEL UC 8000 building management system fitted within the boiler house which controls the heating plant through a three port valve fitted at high level. It is not known if this is a slave panel to a remote building management system. This particular JEL unit is now obsolete and will need to be replaced at the same time as the boiler plant. (see below additional information) See photo 6 Gas Advisory Services Limited Page 5 of 14

7 Pipe Work All pipe work that is visible within the boiler house is steel with small amount surface rust in some areas but generally appears in satisfactory condition with no visible leakage. The underground heating mains leave the boiler house in brick built ducts which are dry and sound. All pipe mains within the duct that could be inspected were well insulated with Rockwall foil finish with small amount of damage to the insulation due to maintenance works. Majority of isolation valves that were tested operated correctly Taking into account the age and condition of the pipe work this should have a further life expectancy of years. Boiler House The boiler house was clean and tidy with the floor having recently been painted. There were health & safety signage in place but these require updating. There was no gas line diagram visible but there was a services schematic line diagram fitted on the wall. The boiler house also had in date fire extinguishers fitted. There was log book on site to record visits and within this log book there were engineer service reports. We could find no records of gas safety tightness testing, electrical periodic testing or chimney inspection. Domestic Hot Water There are three sets of domestic hot water Calorifier s. One set located within main boiler house. Second set located within Dunton Ct plant room. Third set located within Thetford Ct plant room. Gas Advisory Services Limited Page 6 of 14

8 Main Boiler House Calorifier s The two vertical galvanised Calorifier s located within the main boiler house serve domestic hot water to Bromliegh and Parfew Ct and each has a storage capacity of approximately 3000litres. Both cylinders were operating at 60c. It would be beneficial to install anti-stratification pumps to both cylinders as an improvement to help prevent Legionella Externally both cylinders appear in satisfactory condition no identification plate could be found but it is assumed these cylinders are the original installation and are in excess of 30 years old. See photo 7 Thetford Court Calorifier s Two horizontal galvanised Calorifier s located in Thetford plant room serve domestic hot water Thetford and Alleborough Court each have a storage capacity of 3000litres. Both cylinders were operating at 60c. It would be beneficial to install anti-stratification pumps to both cylinders as an improvement to help prevent Legionella Externally both Calorifier s appear in satisfactory condition no identification plate could be found but it is assumed these cylinders are the original installation and are in excess of 30 years old. See photo 8 Dunton Court Calorifier s Two horizontal galvanised Calorifier s located in Dunton CT plant room serve domestic hot water each has a storage capacity of 1200 litres. Both cylinders were operating at 60c. It would be beneficial to install anti-stratification pumps to both cylinders as an improvement to help prevent Legionella Externally both Calorifier s appear in satisfactory condition but some local pipe work has small amount of surface rust. No identification plate could be found but it is assumed these cylinders are the original installation and are in excess of 30 years old. See photo 9-10 Gas Advisory Services Limited Page 7 of 14

9 6.0 RECOMMENDATIONS AND BUDGET COSTS Boiler The heating boilers are operational and if they are maintained to the current standard along with the new burners that are planned to be fitted, we would expect these boilers to last for the next 3-5 years. A programme of planned investment works needs to be put in place with full boiler and plant renewal. Calorifier s Due to the large storage capacity of all three sets of Calorifier s it is assumed that all have a two hour recovery which would have been adequate when installed 1970 but due to modern day high demand for hot water these Calorifier s struggle to maintain the demand at peak times. All Calorifier s appear in satisfactory condition for their age and well insulated but are coming to the end of their life and should be replaced with high recovery low storage plate generator with buffer tanks within the next 3-5 years. Cost In order of priority:- Works to be carried out within the next 3-5 years Replace gas fired boilers with new high efficiency fully modulation gas fired condensing boilers 305K Hire temporary boilers whilst works are carried out 28K Survey flue stack and possible remedial works 35K Install new building management system with new boiler installation 30K Replace three sets of Calorifier s with high efficiency generators 130K Upgrade all dwellings with new radiators and controls 450K All the above costs have assumed no asbestos present within areas of work Gas Advisory Services Limited Page 8 of 14

10 Additional Information We have been informed by Southwark council technical services, that there is a current investment programme of works in place. These works are to be carried out over the next 12months. Works include for the; Renewal of the burners to the existing boilers Renewal of the existing plant control (JEL unit) The introduction of a dirt separation / filtration system. 7.0 PHOTOGRAPHS 1 Main Boilers and gas burners Gas Advisory Services Limited Page 9 of 14

11 2 Rear of left hand boiler showing corrosion 3 Right hand boiler showing corrosion within casing on boiler shell Gas Advisory Services Limited Page 10 of 14

12 4 Main heating pumps Gas Advisory Services Limited Page 11 of 14

13 5 New pressurisation unit 6 Heating controller JEL Gas Advisory Services Limited Page 12 of 14

14 7 Domestic hot water Calorifier s located within, Bromliegh Court 8 Domestic hot water Calorifier s located in Thetford Court Gas Advisory Services Limited Page 13 of 14

15 9 Left hand domestic hot water Calorifier Dunton Ct 10 Right hand domestic hot water Calorifier Dunton Ct Gas Advisory Services Limited Page 14 of 14