Chemicals or powerflush when replacing boiler in old house?

[SarahD]

Hi there.

I've been reading old posts about power flushing on these boards with great interest and wonder if anyone could offer some advice. We have decided to replace our twenty-ish year old floor mounted Ideal E-type balanced flue boiler. It has been very reliable but very expensive to run. Over last few years quite a bit of the pipework has been renewed/rerouted as we’ve gutted the rooms, mostly reusing the original Stelrad radiators, adding a couple of new ones, heated [url=http://www.plumbworld.co.uk/14-0000]towel rails[/url] etc. The system has had to be drained on several occasions and we now have some kettling and need to bleed the three rads on the top floor occasionally. No heavy sludge in the system, although the water in the rads is discoloured. We are looking to install a Vailant Ecomax Pro wall mounted condensing boiler.

Given that we are two thirds of the way through renovating a large three storey late Victorian house and have fully decorated and carpeted a number of rooms, we do not want the disruption, expense and stress of possible leaks, especially as there are lath and plaster ceilings, ornate ceiling mouldings and cornicing in almost every room. When we first looked into replacing the boiler a couple of years ago, the heating engineer gave us the option of using chemicals rather than power flushing the system but now he is adamant that we really should have a power flush before fitting the new boiler. He left me with the impression that the chemicals would be less likely to cause problems such as leaks and pinholing but consensus on these boards and elsewhere seems to be the opposite. We are also concerned at the cost as there are 17 rads/towel rails. In your experience is the power flushing itself likely to cause leaks (or worse), even if chemicals are not used? What course of action would you take? We do not want to find the heat exchanger packs up in a year but cannot deal with the possibility of damaged ceilings and ripping up carpets after we have come this far!

Thanks for any help

Sarah

[SimonD]

Powerflush it, as per your heating engineers instructions.

We won't fit a condensing boiler without Powerflushing because we want the boiler to do 5 years without any problems. I would imagine you do, too.

The new ecoTEC open vent is a better boiler, have a look at that.

[SarahD]

Thanks for replying!

Looking back over various message boards on the subject has led us to be very cautious so, at the moment, we have decided to power flush but will not be using any chemicals, other than a mild solution of inhibitor at the end. Simply not prepared to risk it. Will have a filter on the new boiler return too as a precaution and possibly Scalewatcher too as limescale is a problem. Spoke to heating engineer and we will be having the latest Vaillant as you mentioned.

Thanks again

Sarah

ps. would anyone else like to add anything?...please!!!

[MIKE K]

Hi

I have just joined the forum. Your article is very interesting because I am in the process of changing my 24 yr old Potterton Kingfisher RS50 floorstanding boiler to a wall mounted Vaillant. Your points on power flushing are similar to my concerns as there is a school of thought that all this is a industry gimmick as apposed to a requirement,Ihave no signs of sludge in the system. British Gas are coming on Mon evening to give me a quote,I shall listen with interest! Perhaps they will surprise me. All I require is a replacement boiler fitted, I can do the rest of the work needed. Have you started your work yet? I shall be using Fernox as a cleanser and inhibitor as I have a radiator to change as well.

Regards Mike

[SarahD]

Hi Mike,

Apologies for the delay in replying, it has been pretty chaotic here. The boiler replacement and associated work has finally finished (although the electrician has to come back as since he signed off the work we have had no hot water!!)

In the end we decided against the use of any chemicals except Sentinell X100 inhibitor and the addition of a removable filter on the boiler return pipe to prevent any bits entering the heat exchanger. From all my reading I was most struck with what The Scruff said earlier on these message boards: “On any old system that has not been dosed or maintained, using chemicals will clean the inside and any weak spots will leak, same thing applies to inhibitors, if its been done before OK if not keep a weak solution”. I believe the Fernox products are stronger than Sentinell and should only be used if you are confident the system and radiators are sound (or you are prepared to deal with leaks and pinholing of radiators!) Scruff also said that a device like scalewatcher/magnaclean fitted to the system will remove limescale/corrosion over a period of time and again expose any weaknesses at a later date.

What I couldn’t get an answer to was whether powerflushing with water only would cause any problems. The heating engineer said no but, when he read the instructions to his, as yet unused, powerflusher he discovered a warning that the customer should be made to sign an indemnity against any damage caused! Says it all I think. We didn’t let him use it and he was quite happy with this as it turned out that the system was pretty clean anyway. It was cold flushed and hot flushed by draining down only- although we have a strong suspicion Sentinell X300 was sneaked in to clean out the flux and solder from the extensive re-piping that we had done (we discovered a couple of bottles with the heating engineers kit!)

Anyway, other than the complete takeover of the house, the mess and the electrician it was all very successful with no leaks or blowing up of radiators! The Vailant is running well with no hitches so far and a vast improvement on the old chunk of metal. Good luck with your work, although I have to say avoid BG if at all possible - I have heard nothing but complaints about them.

Sarah

PS. whatever you do allocate some storage and working space to the fitters, move everything out of the way so there is a clear run to each radiator and cover all the carpets!!

[SimonD]

We Powerflush many 100s of systems a year, of varying age and condition.

The last significant problem we had was three years ago, and the radiators were so corroded they wouldn't have seen the year out with, or without a Powerflush.

We use a Powerflush machine with heat and chemicals because this gives the cleanest result, and is the only manufacturer warranted method. You can get close by removing every radiator (and I mean every) in the house and hosing them out individually. Running a Powerflush machine without chemicals is utterly pointless, I am rather amused how you came to decide on this as a sensible route. Why anyone else should want to heed your advice based upon nil experience is unfathomable.

Like any discussion forum you will get conflicting advice, but what it boils down to is following the advice of the boiler manufacturer.

You may be interested to know that inhibitors swell up rubber/neoprene seals, which causes other boiler problems. In Germany, inhibitor is generally frowned upon and their sealed systems are filled with clean water only - the principle being that one fill of water has only a limited corrosion potential after which the water becomes inert.

[Chris]

[SimonD]

Chris

Time on your hands? Looking at old posts?

My comments were referring to the need for a powerflush, not the heater. You misinterpreted me, but perhaps I could have made my emphasis clearer in retrospect.

Inhibitors can swell up seals; it was two of our boiler manufacturers that advised us of this fact.

I have the choice of taking the opinion of two large scale German boiler manufacturers, from whom we purchase 100s of boilers each year, or some rather tetchy unknown on an internet forum.

The jibes were a bit unnecessary, but then again, this is the ideal place to make personal comments if you are a bit shy with people. I hope it made you feel better.

[Chris]

No Simon, as always your comments were wrong. You simply have to learn to get things right. It matters, if you want to stop looking a fool.

[SimonD]

I have reread your last post a couple of times and cannot see any facts or any point in it, other than satisfying your personal needs.

Is there a Mrs Chris?

[Chris]

None so blind as those who won't see.

The point, if anyone remained in any doubt about you, was to make it clearer what a disreputable individual you are.

[HSP]

chris i think your cooment are going to far!!!

I have been doing powerflushes for a couple of years and have recievd manufacturer training, they along with most other manuifactures will tell you that using the chemical and heat not only speeds it up but is vital to the powerflush process. Water alone will not breakdown the sludge !!

taht is why someon like kamco have fx2 acid cleaner then after that is used a neutraliser is used to to stop any further corrossion for the chemicals once neutralise dthe inhibitor can be added

I have powersflush many old system and never had a problem.

Everyone has a different view on everything and thats fair play , but to personally attack simonD andsay he is a cowboy is going too far.
_________________
Dont cha wish your bouyfriend was a plumber like me !!!

[Chris]

[SimonD]

It is amazing how far some will go to justify not buying a machine with a heater.

If you are skint and have bought a cheapo, admit it.

Disagreeing with those of us who have been on manufacturer courses and the chemical manufacturers themselves, is really not going to persuade anyone.

Even if you resort to making personal comments. They read like desparation, and do nothing for the reputation of our professional heating trade.