Potterton Netaheat replacement

[brsince78]

I have a Potterton Netaheat 16-22 that has given 22 years service. It failed on me last winter. I managed to trace the fault to a dry joint on the printed circuit board and fixed it with a soldering iron. Researching the boiler on the internet makes me realise that its days are numbered and it is not a boiler to tinker with. One forum post referred to it as 'the widowmaker'. Time to replace it I think.

Budget is limited so I am looking to replace the boiler (on the wall in the kitchen) in situ and make the minimum number of changes elsewhere.

I've researched various makes and first chose Worcester Bosch. I've discounted their boilers as the documentation on their website states that they must be supplied by a 22mm gas feed. My feed is 15mm and replacing it would be a major challenge.

My next choice is Vaillant (their boilers state a 15mm gas feed). My current system is open vent with an expansion tank in the loft. A three-way valve in the airing cupboard, and small-bore central heating.

The Netaheat 16-22 is rated as 16-22kw output.

My first questions are therefore:-

1. How good are Vaillant boilers?
2. Is the Vaillant ecoTEC plus 428 (5.3 - 28.2kW) the boiler for me?
3. The cold feed from the expansion tank is fed directly into the back of the Netaheat. (3 pipes drop from the ceiling above the boiler). Can the feed from the expansion tank be simply connected into the Hot feed from the boiler immediately above the boiler?

Thanks in advance.

 

[stevetheplumber]

I have a Potterton Netaheat 16-22 that has given 22 years service. It failed on me last winter. I managed to trace the fault to a dry joint on the printed circuit board and fixed it with a soldering iron. Researching the boiler on the internet makes me realise that its days are numbered and it is not a boiler to tinker with. One forum post referred to it as 'the widowmaker'. Time to replace it I think.

Budget is limited so I am looking to replace the boiler (on the wall in the kitchen) in situ and make the minimum number of changes elsewhere.

I've researched various makes and first chose Worcester Bosch. I've discounted their boilers as the documentation on their website states that they must be supplied by a 22mm gas feed. My feed is 15mm and replacing it would be a major challenge.

My next choice is Vaillant (their boilers state a 15mm gas feed). My current system is open vent with an expansion tank in the loft. A three-way valve in the airing cupboard, and small-bore central heating.

The Netaheat 16-22 is rated as 16-22kw output.

My first questions are therefore:-

1. How good are Vaillant boilers?
2. Is the Vaillant ecoTEC plus 428 (5.3 - 28.2kW) the boiler for me?
3. The cold feed from the expansion tank is fed directly into the back of the Netaheat. (3 pipes drop from the ceiling above the boiler). Can the feed from the expansion tank be simply connected into the Hot feed from the boiler immediately above the boiler?

Thanks in advance.

any 28kw boiler will need a 22mm gas supply regardless of the size of the connection unless its about 4 ft from the meter
vailants are good boilers
unlikly you can take the cold feed in as you suggest there will be a schematic of systems in vailants instructions which is available on there web site cold feed position needs to be relative to the pump and open vent positions
its possible you have a gravity hot water on existing which will have to be changed to fully pumped