Brockhill House is a residential care facility operated by Woking Council, consisting of 54 2 bedroom sheltered dwellings, with bedrooms, lounge, toilet/shower bathroom/wet room and kitchens.
Additionally communal day care room, common areas, hairdressers, meals on wheels offices, administration offices and laundry facility. Operational 24 hours 365 days.
Original installation consisted of 6 modular natural gas fired boilers, 1 natural gas fired water heater, decommissioned natural gas fire CHP, 3x 2000lt water header tanks, 1x 1000lt open vented system header tank, buffer vessel. Local BMS, primary flow and return and secondary return on hot water system.
Retrofit all apartments hot water systems, temperature regulating valves, heating system control, flushing, chemically cleaning and treating, replace the CHP, install renewable air source heating for communal meeting area, install PV solar panels G59 control for exporting.
Remove 7000 litre water storage, upgrade all domestic hot water supplies, replace all plant room equipment with new, pressurise and boost hot water and cold water feed, remove all electric showers and shower pumps.
Replace under pipework to annex.
Retrofit BMS from the basic on/off to a remotely monitored and controlled system, interfacing with clients existing BMS module at their head offices and give onsite staff control access.
Develop supply chain maintenance program with specialist manufacturer for the on-site renewable equipment and ensure critical response with 4 hour on site attendance is in place.
Develop a critical spare parts kit to ensure uninterruptible heating and hot water supplies.
Redesign primary plant and network to ensure maximum performance of the primary plant and upgrade the internal secondary equipment so as to introduce maximum efficiencies.
The primary challenges faced regarding this project were the fact all apartments and areas are in daily use, frail and elderly resident are housed in this facility with dust, noise and obstruction all posing issues. The kitchens for meals on wheels could not be relocated for the duration of the works and we were not permitted to work after 21.00 and could not start before 09.00.
Water tanks were between 1500 litres and 2500 litres resting above residential apartments – these were to be cut out, again noise and dust and inconvenience to the tenants were all serious challenges.
Existing network pipes had been modified and changed throughout the years so no drawing was accurate.
The domestic hot water supply was prone to air locks, dead legs and therefore posed serious issues by not conforming to L8 and interruptions to supply, this had been compounded by sub-contracted maintenance firms installing a mix of electric showers and or booster pumps.
Environmental issue of the CHP location creating an unacceptable noise level when in operation.
Underground pipe installation to the annex route was directly through the drive of the ambulance and meals on wheels service.
Our appointment was as a result of a site survey, inspection and detailed report on potential savings of energy production costs.
Due the operational nature of the site it was necessary to have lengthy discussions with the day and night staff as our standard working day would involve both shifts. We took the decision to have daily meetings between our on-site foreman and the duty officer of the care facility.
Out first task was to install a temporary plantroom in the car park of the site adjacent to the existing plant room. We cut into the heating system first, ensured this was operational and consequently we would be able to switch between temporary and primary without any interruptions to supply.
We then had to cut into and pressurize the domestic hot water supply – isolating the open vent and install equipment to enable pressurization.
We were aware this temporary solution would create other issues during the works so we provided a 24 hour response facility manned by our in-house specialists. Due to the nature of the facility and the installation, each call out would have to be manned by two specialists using two way radio communication as mobile phones did not work due to the building fabric.
To avoid unnecessary environmental and additional cost issues with fuel oil deliveries we re-routed the primary gas main and ran the temporary boilers on the client’s main gas supply. This gas installation and the water connection now remain a permanent fixture as part of the performance warranty is to ensure in the event of critical failure heating/hot water would be provided within an 8 hours period. This also meant we have a contract with our specialist supply chain to bring in within 6 hours a trailered gas fired 350kWh boiler to take standard fittings from all types of temporary boilers. The flexible hoses are kept on site and have quick release clamps – the whole critical operation can be completed within 8 hours from the time of the first call.
As the site is laid out as a central plant, with office/admin wing and two residential wings we put three teams of specialists to work, one team stripping out and rebuilding the primary plant. The other two teams began their task at the first apartment on the network and worked away from the primary plant room. As we were using existing network pipes that were in poor condition, we needed to protect the new equipment as it was installed. We installed air dirt separation and side stream filtration on the temporary supply, this not only improved efficiencies during the works it meant that the system network was cleaned and treated constantly.
To remove the tanks from the loft spaces we sealed the loft hatches in the tenants apartments and removed a small section of roofing. The tanks were then cut up while the tenants were.
Installation of the temperature regulation valves in each apartment proved to be simple and acceptable as we purchased plastic storage containers. Prior to starting the upgrade we asked the tenant to empty their kitchen sink base unit and clear the bath room sink area – the tenants were offered assistance by the wardens, the storage boxes were given away to the tenant if they wanted them.
The installation of a new PV Solar array with feed-in tariff was calculated by our design engineer to produce enough energy making the primary plant operation, pumps etc, cost neutral. Any surplus energy was put in to the thermal store as heat/hot water demand in this residential site was high an expensive prior to the works being carried out.
The installation of the CHP was an issue as the previous unit had caused a problem of noise to a local neighbour, our initial inspection suggested the pad and sound proofing was inadequate so this had to be redesigned. We then appointed our legal witness specialist to liaise with the EA, our designers and the neighbours. The results were spectacular, as monitoring showed that the neighbour’s tumble dryer was producing more noise than the CHP at full load.
Our design partners specified a thermal store as part of the design and installation and the BMS was configured to operate with winter/summer settings and an intelligent controller monitoring external weather conditions as well as demand on the system.
We set up a back-to- back maintenance contract for the specialist support direct from supply chain partners regarding the CHP and BMS.
By bringing advice and experience to the client, they were better able to make informed decisions and this allowed us to improve the performance of the entire project.
In order to replace pipework under the road route of the ambulance and meals on wheels, we instructed our specialist civil firm to open up two pits on either side of the roadway and drill through and pull the pre-insulation pipework. The pipework was re-connected, the pits filled in and two manhole service ducts on the joint were installed for future inspection and service.
We have ensured a continued performance warranty with the client and have improved the client’s reputation with its tenants.
The plant room and supply is now reliable providing continuas heat and hws to the tenants , we had also fitted tap in points for disaster recovery , so if at any time in the future emergency generation plant can be connected to site and provide serviced.
Water treatment and continued water monitoring maximizes heat distribution efficiencies.
By using our supply chain, we are able to control our overheads, which allows for the highest quality at the correct cost and ensures designs are flawless and also provides the client with professional indemnities and a wealth of skilled professional personnel.
Controlling hot water temperature in each flat and having the correct sized thermal storage has ensured that even at the highest demand all facilities are supplied adequately.
The installation of a temporary boiler with side stream water treatment and clean, is a very effective way of improving performance and keeping staff safe from accidental burns.
Energy savings were calculated in excess of 47% Approx (£30,000 pa min), due to flows reaching the tenants efficiently, clean and treated network water, total control of heat production and correct modulation between the renewables and CHP on site. Providing information on feed-in tariffs and fuel costs, the BMS system could select when to use the CHP, solar and natural gas supply, adding to the overall savings achieved.
CHP production in this environment where heat is the primary demand reduces the importing of electricity to zero and often runs with an output and revenue.
Having removed all the hot water system dead legs and cold water storage we have saved the client a quarterly bill from a water treatment specialist.
By pressurising the water supplies we have removed all electric showers, this has lowered the incoming power requirements of the site and lowered the power consumption.