gas hob in new extension

[masamune]

I have a new gas hob fitted in my extension kitchen.
The builder deemed it was sufficient to install this by himself because he believes is just a bayonet connection and the pipework bringing the gas has already been done/tested by his gas plumber (for the record I have not been there to see him doing that anyway).

This is obviously not the proper way to do things, he should called his gas plumber.

Some concerns/questions. Note that I am not using the hob until this is properly checked!

a. He picked up a hose from my old gas cooker that he re-used. Firstly I don't understand why we should be using old materials, if anything. And secondly why is this suitable...

b. The gas hob installation manual says: "gas connection: the end of the inlet connection point has a 1/2'' thread 20.955mm that allows for: 1. a fixed connection, 2. connection using a flexible pipe L min 1m - max 3m. The watertight seal (034308)" supplied must be inserted between the manifold outlet and the gas supply"

c. Is there a need for an isolate valve?

d. My gas plumber was around last night to check the boiler and said that as far as he knows the connection should be rigid. If a hose used as per the manufacture it should be a metal sheathed hose. Before getting him to test/replace I wanted to bring this up with the contractor who is in charge of this work.

Photo attached


I am getting confused over requirements for gas and building regs certification. Does the builder have to certify this somehow or just install and checked properly with a gas engineer. In which case I will request his gas engineers come around and tests for leaks /confirms it is "safe" for use on his own cost.

The Gas safe website says:
A Declaration of Safety certificate is produced when a flueless gas cooking appliance (such as a cooker or hob) is notified. These are not covered by the Building Regulations but can be voluntarily notified.

 

[muggles]

There is nothing in the regulations to say that the hose used by your builder is prohibited. Quite the opposite in fact - the regs say that it is permitted unless the hob manufacturer's instructions state that it's not permitted.

However, your builder is most certainly not permitted to make the connection between hose and hob unless he is Gas Safe Registered and holds a CCN1 and CKR1 qualification. Personally I wouldn't re-use an old hose either, I'd want to see a new one in there, but if the old one is in very good condition there's nothing technically wrong with re-using it as far as I'm aware.

You should probably also check the clearances between the hob and any units and/or extractor fan above before you call your builder as well, to ensure that these comply with the manufacturers instructions. Better to get him to sort everything properly on one visit

 

[masamune]

However, your builder is most certainly not permitted to make the connection between hose and hob unless he is Gas Safe Registered and holds a CCN1 and CKR1 qualification. Personally I wouldn't re-use an old hose either, I'd want to see a new one in there, but if the old one is in very good condition there's nothing technically wrong with re-using it as far as I'm aware.

Thanks.

I'm most certain he is not qualified and just making things up. The question is, would this be the correct flex hose? They used a bayonet converter in order to use the old cooker hose. Also he is not the right person to judge the condition of the cooker hose.

My gas plumber insisted he would be using a rigid connection to his experience but also agrees the manufacturer's installation manual overrides this. Although he disagreed with the cooker rubber flex.

 

[FiremanT]

The rubber hose is okay.Your "gas plumber" is getting confused, probably with commercial requirements. There is a strong, but wrong, belief that a hose can only be used if the MIs say so. In fact, as per Muggles (his entire post is sound) , the reverse is true, a hose is permissible unless the MI state otherwise. the bayonet is also okay.

This is an odd situation though. If MIs state something contrary to the default "regs", it is normally to relax the rules, (presumably because the appliance has been successfully tested against the revisions) so if we have the MIs we follow those, if not, we go to default. In this instance, the "default" would be wrong.

 

[masamune]

The rubber hose is okay.Your "gas plumber" is getting confused, probably with commercial requirements.

"Heating engineer" if you prefer
Fair enough. Shouldn't it be a new hose at least as the condition cannot be verified by a builder?

so if we have the MIs we follow those, if not, we go to default. In this instance, the "default" would be wrong.

I didn't quite understand the last line, can you elaborate why the default would be wrong in this case?

What would you recommend going forward. The builder is difficul to keep to his word. Should I have the hose replaced with a new one for the peace of mind and certify?

My gas plumber/heating engineer will charge full service price which is an overkill but gas is not something to risk with...

 

[FiremanT]

"Heating engineer" if you prefer
Fair enough. Shouldn't it be a new hose at least as the condition cannot be verified by a builder?



I didn't quite understand the last line, can you elaborate why the default would be wrong in this case?

What would you recommend going forward. The builder is difficul to keep to his word. Should I have the hose replaced with a new one for the peace of mind and certify?

My gas plumber/heating engineer will charge full service price which is an overkill but gas is not something to risk with...

I meant that a hose is okay, I cannot comment on the old hose,as I haven't seen it.

I didn't quite understand the last line, can you elaborate why the default would be wrong in this case?
Because the default is that you CAN use a hose. Which would be wrong if the MIs said you cannot.This comment was really directed at the pro's TBF

My gas plumber/heating engineer will charge full service price which is an overkill but gas is not something to risk with.
Ordinarily, I would question why you should think charging his full price is over kill. But he doesn't actually know the rules- is he registered for cookers (CKR1)?

 

[masamune]

I meant that a hose is okay, I cannot comment on the old hose,as I haven't seen it.

I meant the type of hose. He used the "cooker" hose which I understand is fine but there is also a hob mate metal hose on the market. I am not saying one is wrong just trying to understand why the different types?

Ordinarily, I would question why you should think charging his full price is over kill. But he doesn't actually know the rules- is he registered for cookers (CKR1)?

I have looked him up before and he is registered for gas work across the board

What I was trying to establish is whether I need a full certification or a visual/leak test? or replace the hose entirely and get it certified. What would you recommend?