Boiler Powerflush or Mains Flush

silps

Hi, I have been getting some quotes to have a new boiler fitted and I am going to go for an open vented system because I don't want to risk any leaks with a closed system.

The most reasonable quote I have had is recommending to do a mains flush on the radiators instead of a powerflush. He said it is because my rads are 20 years old and the chemicals used as part of a powerflush might stir things up too much in the radiators which could end up leaking.

Does this sound like a good idea or should I just go for a powerflush as all the other quotes have recommended? We do have sludge in the system (rust inhibitor has been added) but I don't have any problems with the radiators heating up.

He recommended a magnetic filter but others have said they don't do much.

Also he recommended a Main brand boiler with a cast iron heat exchanger rather than a Vailant as the cast iron would last longer.

Thanks for any advice you can offer.

gartshore

where are you based & what size of property is it .

rdpro

silps wrote: »

Also he recommended a Main brand boiler with a cast iron heat exchanger rather than a Vailant as the cast iron would last longer.

Thanks for any advice you can offer.

Can't see how cast iron, that goes rusty in a moist wind, would last longer than a Vaillant stainless steel exchanger!

EliteHeat

silps wrote: »

Hi, I have been getting some quotes to have a new boiler fitted and I am going to go for an open vented system because I don't want to risk any leaks with a closed system.

The most reasonable quote I have had is recommending to do a mains flush on the radiators instead of a powerflush. He said it is because my rads are 20 years old and the chemicals used as part of a powerflush might stir things up too much in the radiators which could end up leaking.

Does this sound like a good idea or should I just go for a powerflush as all the other quotes have recommended? We do have sludge in the system (rust inhibitor has been added) but I don't have any problems with the radiators heating up.

He recommended a magnetic filter but others have said they don't do much.

Also he recommended a Main brand boiler with a cast iron heat exchanger rather than a Vailant as the cast iron would last longer.

Thanks for any advice you can offer.

That all sounds quite reasonable to me. The magnetic cleaner that he is referring to is either a Magnaclean or a Boiler Buddy. I don't know much about the second one, but I have fitted loads of Magnacleans and can verify their effectiveness.

Re the comment about the cast iron HE, this will outlast the boiler by years. Be aware that the boiler is a "B" rated one and is very slightly less efficient that an "A" rated one. Not much in it though.

Razor

Hi, the cast iron HEX might last a long time but the rest of the boiler is not great, if you're not keen on a powerflush and your old boiler is working why not get him to fit a magnaclean now and dose the system with X400, empty the magnaclean frequently depending on how much crud it collects, then a cold and hot flush when the new boiler goes in, personally I would go for a 400 series Vaillant every time or a WB Ri model

plumb1_2

I would get your plumber to do a TDS test & PH test on your system .
Doing a mains flush will not remove much over 50% of your sludge, and is messy job disconecting all of your rads to take out side to flush with a hose.

A powerflush and the use of x800 and a rad hammmer will remove 90%, also recomend a Magnaclean or a Magmaster (better product imo) be fitted.
If your rads are showing signs of rust? best to replace them now rather than they start to leak in the night or xmas day.

silps

Thanks for all your replies. The mains flush he was referring to was by leaving the radiators in place but closing them all and then one by one open the valves and flush them with water.

I think I will go with the plumber that is going to do a powerflush but he recommended Potterton Promax boiler and if I want a Valiant then that would cost £400 more. He wasn't too keen on a magnaclean but I could ask him to fit one anyway.

Also our expansion tank boils over (i.e. hot water going into tank drawing air into system) because we used to have a gravity system and British Gas years ago fitted an extra pump to turn it into a fully pumped system. A couple of the plumbers said that once they fit the pump and two valves that should sort the problem. Is this correct?

It is very hard to know what to do because they all say something slightly different to each other.

plumb1_2

Make sure your plumber spends a min 4hrs powerflushing your system.
It cannot be done in less time, the min i spend is 5+ hours.