Client: Site: 4 th March 2014 Renewable heating and hot water tender specification for main house and cottage Author: Doug Johnson Revision: 01A Renewable heating and hot water tender specification rev 01A 1 of 11
1 Contents 2 Introduction... 3 3 Scope... 3 4 Statement of Requirements (SoR)... 4 4.1 System design... 4 4.2 Site preparation... 4 4.3 Access... 4 4.4 Equipment supply and storage... 4 4.5 Design and performance criteria (heating and hot water)... 5 4.6 Ground works... 5 4.7 Equipment installation... 5 4.8 Commissioning and acceptance testing... 5 4.9 Hand over process... 5 5 System detail (House)... 6 5.1 Plant and plumbing schematics... 6 5.2 Plant and service locations... 6 5.3 Specifications... 6 5.4 Overall system performance... 7 5.5 System interface requirements... 8 6 System detail (Cottage)... 9 6.1 Plant and plumbing schematics... 9 6.2 Plant and service locations... 9 6.3 Specifications... 9 6.4 Overall system performance... 10 6.5 System interface requirements... 10 7 Quality requirements... 11 8 Timetable and scheduling... 11 9 Plant schematics......12 Renewable heating and hot water tender specification rev 01A 2 of 11
2 Introduction As part of a site wide building improvement program at XXX there is the requirement for two separate renewable energy heat pump systems to be installed to supply heating and hot water to both the main house and the adjoining cottage. It is planned that these individual systems will provide all of the heating and hot water all year round for both these buildings and reduce running costs considerably. A remote plant room is being constructed to the North East of the cottage to house additional plant equipment for the heat pump systems and an area of nearby pasture land has been set aside for use to collect energy from the ground. 3 Scope The contractor will supply, install, integrate and commission two separate heat pump systems to provide heating and hot water for the main house and cottage. The contractor will be wholly responsible for: 1. Supply and installation of an air source heat pump system in the cottage providing a supply of heating water and on-site hot water storage. 2. Supply, installation and integration of a bivalent ground source heat pump system with the existing domestic oil boiler providing a supply of heating water and on-site hot water storage. 3. Installation of all underground heating water, inter-equipment communications and control services necessary for ground source heat pump operation between the proposed remote plant room location and the existing house plant room location. 4. Specification and communication with the main contractor of necessary ground works requirements to successfully install the heat pump systems. 5. Fully renewable heat incentive (RHI) scheme installation eligibility and installation of appropriate metering. 6. The provision of aftersales warranty, maintenance and operational support for both heat pump installations after the commissioning date. Renewable heating and hot water tender specification rev 01A 3 of 11
4 Statement of Requirements (SoR) 4.1 System design The final detailed hydraulic, electrical and control design must be fully compatible with microgeneration scheme (MCS) guidelines, follow industry best practice and meet the performance specifications outlined further on in this document. The contractor will be expected to liaise with the designers and installers of the underfloor and radiator system and share key technical design information to ensure full thermal and control performance throughout both buildings. Final and appropriate ground loop sizing and subsequent ground source heat pump collector field area must be determined by the contractor based on the required energy demands of the main house and the specific ground conditions on site. Note: A ground condition report with and soil thermal conductivity values will be provided to the contractor allowing for ground loop collector field area calculations to be completed. The contractor must finalise RHI metering detail, heat emitter sizing and ground loop sizing calculations and ensure documents are presented to the client (or their chosen representatives) as per MIS3005. 4.2 Site preparation The contractor will review and document where appropriate any existing plant room plumbing before works on site and ensuring full hydraulic system functionality is retained after the installation of the heat pump systems. The contractor will be responsible for ensuring any remaining plant room pipework is power flushed and cleaned of debris before connecting any heat pump equipment to the system. 4.3 Access The contractor will be responsible ensuring that equipment does not require any special access requirements onto site and if so will be required to highlight specific requirements as part of their tender submission. 4.4 Equipment supply and storage All heat pump equipment installed will be MCS registered and eligible in full for government RHI grants. Provision must be made for any delivered equipment to site to be offloaded personally by the contractor to reduce the risk of third party damage. In addition the contractor must supply their own means by which to unload and transport all necessary equipment and material around site. All equipment delivered to site will remain at risk and uninsured until fully installed on site. As a result contractors must ensure any materials, equipment and tools are adequately insured. Details of insurance held must be provided as part of the tender submission. Renewable heating and hot water tender specification rev 01A 4 of 11
4.5 Design and performance criteria (heating and hot water) Within the main house a bivalent ground source heat pump and oil boiler system will together provide 100% of home heating down to an outside temperature of -1.8 o C. Within the main house the oil boiler installation will provide 100% domestic hot water heating requirements down to an outside temperature of -1.8 o C. Within the cottage an air source heat pump system will provide 100% of home heating and hot water production down to an outside temperature of -1.8 o C. 4.6 Ground works It is not within the scope of this tender to provide services for ground works for any required ground collectors or service trenches. It is however the contractor s responsibility to supply all necessary ground loop manifold hardware with full details of any preliminary ground work requirements at the request of the main contractor 4.7 Equipment installation All necessary equipment, fittings and meters will be supplied and fully installed in allocated plant rooms and outdoor locations according to manufacturer guidelines, industry best practice and relevant MCS requirements. It is the contractor s responsibility to supply and install all necessary underground pipework and control cabling from the heat pump plant room to the existing household plant room. 4.8 Commissioning and acceptance testing A testing schedule for heating and hot water supply performance testing will be required for formal review during the installation phase of the project and will be used as part of the onsite commissioning sign off process for both heat pump system to prove full operation capability. Upon final commissioning a full set of heat pump compliance documents necessary for MCS compliance and RHI application for both heat pump systems will be completed by the installer. The ground loop system will be fully pressure tested, flushed of air bubbles and protected against freezing as per MIS3005 guidelines. Pressure test and pipework warranty certificates will be required upon commissioning. 4.9 Hand over process Upon completion the contractor will explain to the client general maintenance requirements and maintenance services available as well as RHI meter reading procedure. In addition for formal records a complete set of documents shall be provided to the client and main contractor which include: - Final hydraulic, electrical and system control schematics as installed - MCS compliance certificates for the heat pump systems - Ground loop pressure test certificates - A full set of user manuals - Warranty certificates - Documented process for reading and submitting RHI energy values - Support with RHI application - Support and maintenance cover Renewable heating and hot water tender specification rev 01A 5 of 11
5 System detail (House) 5.1 Plant and plumbing schematics See attached drawings GSHP schematic and Oil boiler schematic at the rear of this specification document. 5.2 Plant and service locations See attached drawings Site Plan at the rear of this specification document. 5.3 Specifications 5.3.1 Heat pump system Heat pump - Vaillant GeoTHERM 46kW VWS/2 heat pump or equivalent Remote monitoring module VR Net Dialog or equivalent Buffer cylinder Unvented 1000ltr stainless steel cylinder with top and bottom temperature sensor pockets 5.3.2 Ground collectors Ground loop manifold chamber Go Geothermal circular chamber manifold (factory pressure tested) or equivalent. N.B. Final chamber specification and number off to be determined by installer. Tichelmann connection methodology will be implemented for the connection of individual ground loops and multiple manifold enclosures. Ground loop manifolds must allow for individual loop isolation and loop flow rate measurement. The manifold or associated assembly components are to be non-ferrous. Provision will be made to automatically air vent ground loops at the manifold chamber position. Ground loop collector pipework is to be medium density polyethylene (MDPE) or high density poly ethylene (HDPE) with no buried compression joints or connections. Fusion welded connections at the manifold location will be acceptable. Slinky type collectors must be avoided where at all possible with a traditional equally spaced straight pipe layout preferred. Minimum ground loop antifreeze concentration mixture ratio of glycol to water of 1:2 (33% concentration) to be achieved allowing for freeze protection down to -14 o C. 5.3.3 Hot water storage Hot water storage for the main house will remain in the existing plant room with the following replacement upgrade: Hot water cylinder - Heatrae Sadia Megaflo Eco Plus Unvented Cylinder (Indirect) 400ltr or equivalent Immersion Electric 3kW minimum 5.3.4 Pipework Insulated underground pipework between plant room and house Uponor Thermo Twin 2x63mm OD (51.4mm ID) or equivalent Plant room pipework All copper pipework to comply with EN1057 and fittings to EN1254 Renewable heating and hot water tender specification rev 01A 6 of 11
Plant room pipe insulation 20mm Rockwool Rocklap insulation or equivalent Pipework design and sizing It is the contractors responsibility to complete all pipe sizing calculations in line with best practice guidelines and heat pump performance requirements. Pipework and low pressure loss isolation valves must allow for a heat meter to be installed as per MCS Domestic RHI metering guidance document v1.0. All high points in pipework system must have automatic air vents fitted. All pipework must be clearly labelled using Identotape pipe ID wrap (or equivalent). Key equipment items also to be clearly labelled: - Expansion vessels - Circulation pumps - Dosing points - Any incoming services - Electric and heat metering equipment 5.3.5 RHI Metering The installation will have heat and electricity meters fitted according to MCS Domestic RHI metering guidance document v1.0. A heat meter (min Class 3) will be fitted in heat pump return pipework. Flow temperature sensors will be installed in appropriate fittings allowing for flow and return fluid temperatures to be measured within 2m of heat meter. An electricity meter (min Class A) will be fitted on the heat pump electrical supply. 5.3.6 Ancillary equipment Inline heating water filters Filterballs or double isolated inline Y filters to be fitted in return pipe work to allow for simple and easy filter cleaning without draining down large sections of the system. Inhibitor dosing - Hamworthy Horton HN-3.5 inhibitor dosing pot (or equivalent) Magnetic filter - Sentinel (or equivalent). Circulation pumps Grundfos (or equivalent). Drain and isolation points Best practice must be followed to ensure effective future maintenance of the system. Automatic heating system pressurisation Mikrofil Electronic Filling Device (EFD) or equivalent 5.4 Overall system performance The heat pump system alone system will be capable of providing adequate heating of the heat pump buffer storage cylinder to a temperature of 50 o C degrees at a measured outdoor air temperature of 4 o C without secondary electrical heating assistance. The bivalent system as a whole will be capable of providing an estimated maximum constant supply of 45 o C water at a rate of 3.5ltr/s from the low loss header installation to supply all underfloor heating manifolds and radiator circuits. Final flow rate requirements will be determined based on final underfloor heating and radiator schedule and design. Renewable heating and hot water tender specification rev 01A 7 of 11
The control system will allow for the oil boiler to be activated and serve 100% of the home heating and hot water requirements in the event of a heat pump fault or power failure. The hot water storage capacity installed shall be upgraded from the existing 250ltr Megaflo tank to a single equivalent 400ltr unvented tank. Hot water will be supplied and recharged by the oil boiler only. Hot water reheat times from a fully cold tank (nominally 13 o C) to tank storage temperature of 50 o C should not exceed 15 minutes. The heat pump will be capable of weather compensation control of the stored buffer tank water. The heat pump will be capable of controlling the boiler to run a weekly legionella hot water heating cycle as required. 5.5 System interface requirements The heat pump will be capable of using 400V 3-phase phase electricity to operate. Connection to all electrical power equipment will be supplied and terminated at suitably sized rotary isolators. It is the contractor s responsibility to connect to specify these supplies for the onsite electrician and wire from these points to all necessary heat pump and associated control equipment that is supplied as part of their tender. The heating system will be pressurised and filling points made available. Plant room pipework must allow for simple cold water connection and use of the Microfill Electronic Filling Device for topping up of system pressure as required. The heat pump will be capable of communication via GSM or Ethernet to allow for external monitoring of performance after installation. Supply and installation of heating circuit distribution pumps as well as control wiring for any underfloor or radiator distribution system is not required in this tender. Isolation valves will be fitted as per supplied schematics for on-site plumbing trades to connect to. Renewable heating and hot water tender specification rev 01A 8 of 11
6 System detail (Cottage) 6.1 Plant and plumbing schematics See attached drawing ASHP Schematic at the rear of this specification document. 6.2 Plant and service locations See attached drawing ASHP location at the rear of this specification document. 6.3 Specifications 6.3.1 Heat pump system Heat pump Vaillant GeoTHERM Air 15kW 230V heat pump or equivalent Buffer cylinder 40 ltr wall-mounted or equivalent 6.3.2 Hot water storage Hot water cylinder - Heatrae Sadia Megaflo Eco Plus Unvented Cylinder (Indirect) 250ltr or equivalent Immersion Electric 3kW minimum 6.3.3 Pipework Plant room pipework All copper pipework to comply with EN1057 and fittings to EN1254 Plant room pipe insulation 20mm Rockwool Rocklap insulation or equivalent Pipework design and sizing It is the contractors responsibility to complete all pipe sizing calculations in line with best practice guidelines and heat pump performance requirements. Pipework and low pressure loss isolation valves must allow for a heat meter to be installed as per MCS Domestic RHI metering guidance document v1.0. All high points in pipework system must have automatic air vents fitted. All pipework must be clearly labelled using Identotape pipe ID wrap (or equivalent). Key equipment items also to be clearly labelled: - Expansion vessels - Circulation pumps - Dosing points - Any incoming services - Electric and heat metering equipment 6.3.4 RHI Metering The installation will have heat and electricity meters fitted according to MCS Domestic RHI metering guidance document v1.0. A heat meter (min Class 3) will be fitted in heat pump return pipework. Flow temperature sensors will be installed in appropriate fittings allowing for flow and return fluid temperatures to be measured within 2m of heat meter. An electricity meter (min Class A) will be fitted on the heat pump electrical supply. 6.3.5 Ancillary equipment Inline heating water filters Filterballs or double isolated inline Y filters to be fitted in return pipe work to allow for simple and easy filter cleaning without draining down large sections of the system. Renewable heating and hot water tender specification rev 01A 9 of 11
Inhibitor dosing - A suitable dosing point must be installed in the plant room. Final design is at the installer s discretion. Circulation pumps Grundfos or equivalent Drain and isolation points Best practice must be followed to ensure effective future maintenance of the system. Automatic heating system pressurisation Mikrofil Electronic Filling Device (EFD) or equivalent 6.4 Overall system performance The system will be capable of providing adequate heating of the heat pump buffer storage cylinder to a temperature of 50 o C degrees at a measured outdoor air temperature of -1.8 o C without secondary electrical heating assistance. The system will be capable of providing an estimated maximum constant supply of 45 o C water at a rate of 0.5ltr/s from the buffer installation to supply all underfloor heating manifolds and radiator circuits. Final flow rate requirements will be determined based on final underfloor heating and radiator schedule and design. The hot water storage capacity installed shall be a minimum of 250ltr. Hot water reheat times using the heat pump only from a fully cold tank (nominally 13 o C) to tank storage temperature of 50 o C should not exceed 70 minutes. Hot water reheat times using the heat pump and backup electric boost heating from a fully cold tank (nominally 13 o C) to tank storage temperature of 50 o C should not exceed 45 minutes. The heat pump will be capable of weather compensation control of the stored buffer tank water. The heat pump will be capable of controlling a weekly legionella hot water heating cycle. 6.5 System interface requirements The heat pump will be capable of using 230V single phase electricity to operate fully. Connection to all electrical power equipment will be supplied and terminated at suitably sized rotary isolators. It is the contractor s responsibility to connect to specify these supplies for the onsite electrician and wire from these points to all necessary heat pump and associated control equipment that is supplied as part of their tender. The heating system will be pressurised and filling points made available. Plant room pipework must allow for simple cold water connection and use of the Microfill Electronic Filling Device for topping up of system pressure as required. Flow and return termination points from the buffer will be isolated and pressure tested prior to connection by the underfloor and radiator installer. Supply and installation of heating circuit distribution pumps as well as control wiring for any underfloor or radiator distribution system is not required in this tender. Isolation valves will be fitted as per supplied schematics for on-site plumbing trades to connect to. Renewable heating and hot water tender specification rev 01A 10 of 11
7 Quality requirements The contractor must be MCS accredited as laid out under guidelines MCS001. In addition the installer must be a member of the Renewable Energy Consumer Code (RECC). All relevant MCS design supply and installation standards should be complied with, including but not limited to: - MIS 3005 heat pump standard v4.0 - MCS 021 heat emitter guide v1.0 - MCS 022 Supplementary information 1: ground loop sizing tables v1.0 - Heat loss calculation design standard (BS EN 12831) - MCS Domestic RHI metering guidance document v1.0 In addition all relevant standard plumbing component, installation competency and quality standards should be adhered to, including but not limited to: - Domestic hot water design and supply standard BS EN8558:2011 - Pipework - EN1057 - Pipework fittings - EN1254 - Part L: 2013 compliance 8 Timetable and scheduling As part of the tender submission proposed delivery, installation and commissioning schedules for heat pump installations on both the main house and cottage should be submitted. Renewable heating and hot water tender specification rev 01A 11 of 11
SYMBOL KEY Temperature and pressure relief valve P T M Pressure indicator Temperature indicator Isolation valve Double check valve Tundish Flow indicator Motorised 3-port valve Inhibitor dosing point Magnetic particle filter AV AV Discharges piped to suitable drain Ground Loops. -All loops to be of identical lenght -No joints are to be used except where permanent access chambers are installed -Isolation to be provided for each loop -Loop are to be connected to manifolds by a reverse return (Tichelmann) scheme Expansion vessel P Strainer. Isolation valves to be provided such that screen can be serviced without undue loss of fluid Vaillant Geotherm 46kW GSHP Discharges piped to suitable drain P Secondary Pump Expansion vessel P θ Heat meter Mains cold (filling loop) M Buffer tank (~1000 ltr) AV AV AV U/G pipe to house 2x 51.4mm ID PEX 55m Nominal length (Uponor Thermo Twin or similar)
U/G pipe to house 2x 51.4mm ID PEX 55m Nominal length (Uponor Thermo Twin or similar) Expansion vessel P Oil Boiler (existing) Mikrofill pressurisation unit Mains cold (filling loop) Θ Boiler Pump Thermostatic blending valve 400 ltr DHW Cylinder Mains cold DHW Services Expansion vessel T DC P Flow indicators to be fitted on both radiator and under floor heating circuits flow pipework P T Works to be terminated after low loss header at isolation valves. Distribution pipework, pumps and zone controls to be installed by others. SYMBOL KEY Radiator Pump UFH Pump Temperature and pressure relief valve Pressure indicator Temperature indicator Isolation valve Double check valve Tundish Flow indicator Motorised 3-port valve
FLOWE RBE D PT5 1 2 AP New plant room GSHP plant room (oil) GSHP Heat main route GSHP Collector trench route GSHP manifold location (approx) Ground Loop Area A 547m² 0m 5m 10m 15m 20m 25m Ground Loop Area B 542m² Ground Loops to be extended into this area as required by site coinditions. DE