Hello,
I’ve bought a Vitodens WB1B316 Compact Heat Only Boiler, part no. 7416307, for use on an sealed system, replacing a 17 years old Baxi Potterton Promax 24HE.
I'm trying to understand what do I need to get exactly for the Vitodens to work in a sealed system, as I'm supplying all the parts for a labour only installation.
The current system includes:
1) Baxi boiler with external PRV valve on the flow pipe next to it.
1) Megaflo 145CL indirect unvented hot water cylinder (itself with a pressure relief valve, which discharges into a tundish) in the airing cupboard;
2) Extravarem 18l expansion vessel (UR018231CS000000) and PRV valve, located next to the Megaflo cylinder (see photos);
3) Grundfos pump, also located next to the Megaflo.
On their website Viessmann say that 'Whilst being specifically designed for open vent heating systems, the Vitodens 100-W Open vent is suitable for sealed systems using an additional expansion vessel safety valve.'
I contacted them to get more details but they simply repeated that and that is needed to install the open vent Vitodens in a sealed system is 'a kit with expansion vessel and relief valve to do this as below,' and they attached a photo (the red expansion vessel attached).
My question is: am I right in thinking that all that's needed is what is already there in the current setup with the baxi, namely a PRV valve on the flow pipe to the Vitodens?
In other words, is the expansion vessel and PRV valve next to the Megaflo sufficient for the system, or do I need to install a second expansion vessel next to the Vitodens? The Vitodens will be in a kitchen cupboard so i don't see how that will be possible...
Thanks in advance for any advice.
====================================
You can only fit a boiler if you're competent, which means e.g. being Gas Safe Registered.
Clearly you're neither of those.
Same applies to the unvented hot water cylinder which has separate requirements for registration.
We won't give you advise on how to do something illegal/dangerous.
Please See the forum rules.
I’ve bought a Vitodens WB1B316 Compact Heat Only Boiler, part no. 7416307, for use on an sealed system, replacing a 17 years old Baxi Potterton Promax 24HE.
I'm trying to understand what do I need to get exactly for the Vitodens to work in a sealed system, as I'm supplying all the parts for a labour only installation.
The current system includes:
1) Baxi boiler with external PRV valve on the flow pipe next to it.
1) Megaflo 145CL indirect unvented hot water cylinder (itself with a pressure relief valve, which discharges into a tundish) in the airing cupboard;
2) Extravarem 18l expansion vessel (UR018231CS000000) and PRV valve, located next to the Megaflo cylinder (see photos);
3) Grundfos pump, also located next to the Megaflo.
On their website Viessmann say that 'Whilst being specifically designed for open vent heating systems, the Vitodens 100-W Open vent is suitable for sealed systems using an additional expansion vessel safety valve.'
I contacted them to get more details but they simply repeated that and that is needed to install the open vent Vitodens in a sealed system is 'a kit with expansion vessel and relief valve to do this as below,' and they attached a photo (the red expansion vessel attached).
My question is: am I right in thinking that all that's needed is what is already there in the current setup with the baxi, namely a PRV valve on the flow pipe to the Vitodens?
In other words, is the expansion vessel and PRV valve next to the Megaflo sufficient for the system, or do I need to install a second expansion vessel next to the Vitodens? The Vitodens will be in a kitchen cupboard so i don't see how that will be possible...
Thanks in advance for any advice.
====================================
You can only fit a boiler if you're competent, which means e.g. being Gas Safe Registered.
Clearly you're neither of those.
Same applies to the unvented hot water cylinder which has separate requirements for registration.
We won't give you advise on how to do something illegal/dangerous.
Please See the forum rules.
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