Summary of issue... No replacement gas valves for Aga cookers are currently available that give the same performance as previously available. There is no timeline for this to be resolved. It is possible, though unlikely, that it is not resolved.
Summary of solution... Existing gas Aga cookers will continue to operate normally until failure of their gas valve. Conversion to electric prior to this or replacement of the cooker completely are possible solutions. We are investigating the possibility of fitting a MK1 upgrade burner unit with Maxitrol valve but this would require the rebuilding of the cooker completely to relocate the gas supply and purchase of new valve, burner and ancillaries.
Since the summer of this year, 2023, we've had problems in our Aga cooker service department with faulty EUROSIT 630 gas valves for gas Aga cookers. Replacing a gas valve is a very common thing to do but we were making many return visits to failed valves and low oven temperatures. The thinking was that SIT, the manufacturer in Italy, had made a bad batch. Yesterday though it became clear there is a wider issue.
Our lead gas engineer is Mark Hawkes. He is a qualified gas engineer with 20 years experience on Aga cookers, there are few with his level of knowledge. He spent yesterday doing considerable research and I've collated his findings into this post for your information.
AGA Rangemaster issued a technical bulletin yesterday confirming an issue with all available EUROSIT 630 gas valves of the type used in most Aga cookers. Only a lower specified version of the valve, with the same part number (AG1M210175) that looks identical, is now available.
These valves are not used only by Aga cookers, we suspect that such a small subset of customers needs were not considered when SIT withdrew the higher specified valve version. I suspect a cost saving exercise.
There are two issues with the valves now in our experience.
- The current valves, even when set to maximum, no longer allow oven temperatures to reach their normal level. It's a substantial difference that all our customers noticed immediately and really renders the cooker much less usable, closer to a slow cooker than a roasting oven! The valves now seem to have a max temperature 100 degrees centigrade lower than previously.
- The valves now have a lower temperature tolerance than previously. This means premature failure when used inside Aga cookers door apertures where they get hot. We've had new valves fail in weeks, Mark estimates most will fail in 1-2 years rather than the 10 years we would have expected previously. What does failure mean? It means the valve starts to leak gas.
There is currently no alternative to the EUROSIT 630 valve for use with Aga cookers. Only old Mk1 gas cooker updates and new 3 oven Aga cookers use a different valve, by Maxitrol, and converting to these is not currently possible.
Why does this matter to most gas Aga cooker owners? Uncertainty primarily. If your cooker is working normally then you don't need to worry immediately but it is possible that when you need a new valve (as previously noted they usually last around 10 years) it simply may not be available. AGA Rangemaster do state in their bulletin that they are working with SIT to find a solution but there is some doubt in the industry that SIT will be willing to make relatively small numbers of the more robust version of the valve for Aga cooker owners or, if they do decide to make them again, how long this might take.
As a company we service, repair, rebuild and commission gas cookers - this is very bad news for us! The only solution we currently have for those who want certainty from their gas Aga range cooker is to convert to electric or replace the cooker entirely with one powered by electricity.
What sort of issues do gas Aga cookers have that mean a new EUROSIT 630 gas valve needs to be fitted during a service or repair?
Most common is a broken button/igniter or a gas leak. As the valves age the seals being to leak. Valves are also replaced for thermostat issues like overheating.
How often do gas valves need replacing on Aga cookers?
The previously available, more robust, gas valve version we expect to last around 10 years. The older your valve is the more likely it is to fail of course. 10 years is an average too of course. Some fail much earlier, some much later!
What is the issue with the currently available versions of the EUROSIT 630 gas valves?
The valves currently available are designed to be used on the outside of appliances with little or no exposure to heat. Aga cookers mostly have these valves sited in the door aperture so the valves are exposed to considerable heat. Additionally the valves are not set thermostatically to a high enough temperature to satisfy the oven temperatures most are used to in their Aga cooker.
How long has this been an issue?
We've been aware of an issue since the summer of 2023, it became clear yesterday that it relates to all current valve production and not just a 'bad batch' as was initially assumed.
How long are the currently available gas valves likely to last if I put up with much lower oven temperatures and fit one anyway?
We've had the new valves fail in weeks but 1-2 years seems likely to be the average in the professional opinion of our our lead gas engineer Mark Hawkes. Previously we would have expected 10 years approximately.
Is there an alternative gas valve to the EUROSIT 630 that can be used in Aga cookers?
There is a Maxitrol valve used in Mk1 conversion systems and new 3 oven gas Aga cookers but it is not possible to use it in place of the EUROSIT 630. We are investigating whether a complete burner unit and Maxitrol valve combination could be installed. This would require considerable expenditure on parts and also a rebuild of the cooker to relocate the gas supply from the middle of the door aperture to the side.
When will SIT (the manufacturer of the gas valves) find a solution?
The big question! We don't know. There are a lot of Aga cookers but SIT are a very big company - we don't know how motivated they are to recreate the specifications of the 'old' version of the valve or how long it might take if they decide to do so. To withdraw the more robust version must have been a decision many months or even years in the making as their supply chain changed and existing stock was sold. It seems likely that even if this decision is reversed it would take equally long or longer to restart production.
Is it possible there will never be a solution should I need a new gas valve for my Aga cooker?
Yes, we think its possible. AGA Rangemaster don't sell gas cookers anymore or have their own service network who would need to fit them to older cookers. Its an 'arms length' problem for them. This, combined with the relative unimportance of the gas Aga cooker market to the manufacturer in Italy, SIT, could mean no solution is offered.