We have installed numerous Combi ovens in NHS hospitals before, however we have recently been pulled up on a hospital site saying the cold water to the unit needs to be in solid copper with no flexi hose.

The combi’s are Rational, 3 off 201 and 2 off 101 all SCC. There is no softener involved and I believe they are the original hoses that came with the machine.

Does anyone else have similar experience please and whether overcome to remain in flexi or did they have to change?


  1.  We have not ever been instructed to install in copper, but do not do a great of work in hospitals.
  2. It’s becoming increasingly common in Hospitals and Universities. We always now on all taps on sinks have to install on solid pipe no flexi hoses but on appliances we still use hoses as they are manufacturer supplied components normally. I would refer back to the original scope of works or design brief issued, oi client has not advised in advance it’s not fair to then critique or enforce change.
  3. From My understanding the need to use solid pipe connections is recommended wherever possible to remove the possible Pathogen contamination that can be caused by contact with rubber. Here is a link worth reviewing: 
  4. We have had a very recent experience in this and would be happy to help and speak directly to the other member. We have had to use stainless steel pipe with brass fittings.
    Best regards, Richard – Richard Hose,
    Managing Director, Intellico Dishwashers & Glasswashers, T. 0141 465 1234, E:
  5. We have encountered some issues also – In the schools sector this was some time ago – probably around 8-10 years? Information attached, WRAS July edition page 3 and their final advice on Jan 2011.
  6. That’s the first time I have heard that a price of cooking equipment needs to be piped in copper, as far as I’m aware it is not a legal requirement for it to be copper just a personal choice of the designer or architect, as long as the flexi is WRAS approved I’m not sure what the issue is, having said all that it may be prudent to speak to the combi manufacturer.
  7. We have used Mediflex hoses before in a hospital environment, don’t know if they would accept that.
  8. NHS ACTION ON EPDM FLEXIBLE HOSES Advice already issued in Scotland was extended to England and Wales by the Department of Health when NHS Trusts were advised that flexible hoses in wholesome water supply systems in healthcare buildings should be risk assessed for the possibility of contamination with harmful micro-organisms. The concern is that in some circumstances EPDM synthetic rubber (ethylene propylene diene monomer) which is widely used in flexible connectors like tap tails, can support growth of bio-film (a ‘slime’ or growth of microorganisms on the inside of the hose). The biofilm can include legionella, the bacterium which causes Legionnaires Disease. Where risk assessment indicates the need, Trusts are advised to replace EPDM hoses with bendable metallic pipes or flexible ones made of different plastics such as polyethylene (PE), cross-linked polyethylene (PEX), linear low density polyethylene (LLDPE) or post-chlorinated PVC (PVC C) which are believed to be less susceptible to biofilm growth (although further evidence of long-term performance is required). WRAS will continue to approve products made of EPDM that have passed BS 6920 (a test of its effects on drinking water quality). This test eliminates plastic materials which readily support microbial growth, but it doesn’t guarantee that bacteria won’t grow on materials which pass the test. Bacteria, being extremely adaptable, are very good at finding conditions which enable them to grow. Traditionally, biofilm in plumbing systems has been controlled by eliminating the conditions for growth by · avoiding local warming of cold water; · maintaining flow rates and reducing stagnation; · eliminating dead legs; · keeping good disinfectant residual concentrations and · preventing ingress & build-up of debris to limit potential food for the micro-organisms in the water. If in some premises (such as hospitals) these conditions cannot be completely eliminated, it is appropriate to take this into account when selecting materials for the plumbing system. This doesn’t mean that WRAS Approved EPDM hoses are unsuitable for installations elsewhere. 
  9. I would ask your member to ask the question from the relevant NHS Trust as to why? We installed 2 x 20 Grid Ovens in Gloucester Royal on Flexi Hoses. Combi Ovens do vibrate and that having “WRAS” approved flexi hoses nullifies any potential issue with pipework vibrating and then leaking in months/years to come. Also, dependant on size of oven, Flexi Hoses also allow the site to pull ovens out periodically for cleaning/maintenance, without having to disconnect them.
  10. The issue is the potential for standing water and Legionella. The guidelines are particularly applied in hospitals but are applicable to any vulnerable persons, i.e. in schools and care homes.
    We challenge this with then and suggest PEX hoses:
  11. We can’t really help as we don’t do hospital work, however I fail to see what difference it makes being a hospital or any other location, not using a suitable commercial water feed seems nonsense. If it’s a solid connection how do they move the oven?
  12. Whichever hospital has been ‘pulled up’, should ideally contact their oven service provider/installer. We cannot give specific advice on an unknown oven or how it has been installed, or how the oven manufacturer recommends/requires water to be connected. As a general industry rule, any Combi oven that is freestanding or installed on its own stand (particularly o e with castors, but not exclusively), will have a flexi water connection. Either by washing machine type hoses or stainless braided catering water hoses. This method allows for oven movement during use. A solid copper connection will eventually fracture due to stress on use.
    Only large fixed ovens would be supplied with a fixed copper connection. But even these can be fitted with flexi.
    I am not aware of any regulation stipulating the requirement for fixed solid water connection. WRAS states the fittings used must be CE approved and of harmonised manufacture. Also, fittings/work must comply with relevant water standards, not result in wastage of water, or result in damage to fittings/installation or water suppliers supply. This covers check valves to prevent contamination of incoming supply. Connections should of workmanship quality.
    Even gas appliances have flexi Catering hose connections, for same fracturing concerns to comply with relevant Gas Safe Regs.
    I suggest the ceda member contacts their installer/oven service provider.
  13. I did a load of work last year changing all the sink flexy hoses to hard drawn copper due to legionella.
  14. Yes, this is becoming a big issue on Schools/hospitals/Nursing homes etc. So, the way we get around this is to change the specification on the inlet hoses. Mechline do a ¾ inch water hose, but the lining is different, so it is compliant with what most of these sites are looking for. For sinks/wash basins you can make these in on solid fix copper with tap connections, so they are easy. But for combi’s/ dishwashers you will need these higher spec hoses. Part number: Water hose part number is AO6 – PEX. These are at 1200mm long with ¾” hose connections at either end. Mechline sell them. We have just used them again on another hospital and they are happy that we have upgraded on a standard hose.
  15. We have done a number of hospitals this last year with dishwash and hand wash facilities and they all have requested either hard piped or these special braided hoses. I believe it’s to do with legionnaires.
  16. Whilst compliance with the Water Supply (Water Fittings) Regulations 1999 is a legal requirement, there are special guidance requirements for water connections in healthcare premises (Click here to see the document) and the following is an extract from these (Page 18).
    Flexible water supply hoses
    38 Flexible hoses (also known as tails) have become a convenient method of connection between hard pipework and sanitary fittings and/or equipment. They typically comprise a steel-braided outer sheath with a synthetic lining.
    3.39 There have been reports of high counts of Pseudomonas and Legionella in water samples taken from outlets fed by flexible lined hoses due to colonisation of the lining. Materials such as ethylene propylene diene monomer (EPDM) rubber may be susceptible to microbial colonisation. Careful selection of materials for their suitability for wholesome water systems is needed and they should be verified before being used.
    3.40 New lining materials are now available such as polyethylene (PE), cross-linked polyethylene (PEX), linear low-density polyethylene (LLDPE) and post-chlorinated PVC (PVC-C) and should be compliant with BS 6920 (see paragraph 3.1).
    3.41 Flexible hoses should be used only for the following applications:
    • to allow for vibration of equipment;
    • to accommodate vertical displacement of high and low baths and sinks;
    • to facilitate essential maintenance and access of bespoke equipment when no alternative is available.
    Note Where fitted, flexible hoses should be kept as short as possible and be kink-free so as to not affect flow.
    This guidance is open to interpretation by individual Estates Management, however, if they don’t stipulate “solid copper connections” you would certainly be within your rights to request payment for additional work. Please contact ceda Support Advisor ‘Peter Kay’ to discuss this further –
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