Baxi Bahama heat exchanger fault

[merlin]

i have a Baxi Bahama which is about 4 and 1/2 years old, it has always suffered from a couple of problems. 1, the water level keeps dropping and needs constant top ups 2, the boiler often needs resetting.

last year the plate heat exchanger was replaced by Baxi because we were only getting warm tap water now Baxi have said we need the main heat exchancher replaced because we are once again now only getting warm tap water.

can anyone tell me is this common on the Bahama?
Is there a design fault with the Bahama?

Baxi have charged me for a call out and now say i have to pay extra as the heat exchanger is not covered in the call out. I have told them i expected the heat exchanger to last a lot longer than 4 and 1/2 years, they said it due to scale and is caused by my heating system not a fault with the boiler.

can anyone help?

 

[croydoncorgi]

If Baxi replaced a heat exchanger because it was 'scaled up' and did not powerflush the system as part of the job, they should not be too suprised if more scale gets into the boiler later on. OTOH, 4.5 years is a long time to run OK if scale in the Primary circuit (boiler + rads) is the problem. If corrosion inhibitor had been added to the system, scale should not have been as issue. But it seems you also have a leak. If this is long-standing, so that you've been topping up the system a lot, any inhibitor in the system has long since been diluted to uselessness.
So, overall, you're done up like a kipper! But I'm bound to also say that you seem to have had some poor advice along the way. Leaks need fixing when they start. Ignored, they cause a lot of trouble, including most of your current problems.

 

[merlin]

Ok thanks, it looks like i have no option but to pay Baxi more money and replace the heat exchanger, I will ask Baxi to powerflush the system
but i'm not sure they will do it as they say they only work on the boiler.

As for the leak i think the waters running out of the boiler overflow, I cant find any water leaking from my system.

 

[croydoncorgi]

Before you chuck good money after bad, get a competent heating engineer to look at your whole system and advise on the most cost-effective way forward.
To replace a secondary HX instead of trying to clean it first seems 'a bit hasty'. To then suggest replacing the main HX to solve a problem that does not affect your central heating sounds even odder. (your heating is OK???)

 

[ChrisR]

i think the waters running out of the boiler overflow

That definitely needed fixing as soon as it started, as it would lead to the problem you have now. Presumably you've been topping it up since whenever it started - when was that? Did you tell BG ?

 

[merlin]

My heating works fine when the boiler is running, the radiators gets nice and hot. It just the tap water which only comes out warm and the boiler keeps cutting out (just recently its been normally due to low water).

We have always had to top up the water a small bit now and again but its got a lot worse since the last Baxi visit, the same engineer who told me i need a new main heat exchanger.

Do you think the problem is the heat exchanger if i get hot radiators but only warm water?

 

[Baxi-Remeha]

If Baxi replaced a heat exchanger because it was 'scaled up' and did not powerflush the system as part of the job, they should not be too suprised if more scale gets into the boiler later on.

if baxi went out, they are only responsible for the boiler under warranty, and the boiler and valves under a domestic and general contract

maintenance of the system, ie power flushing is upto the customer

 

[corgigazza]

main heat exchanger gets scale in, this inturn clogs up the dhw heat exchanger that acts like a filter, the whole system will need a power flush and possibly a filter fitted on the return to the boiler as i have power flushed before fitted new dhw h.ex and the same problem occur within a month

 

[merlin]

Whats involved in a poweflush? is it something i can do myself or is it a big job?

i have already paid Baxi £200 for the call out and have to get them back
within 28 days to replace the heat exchanger (£275) or they charge another
£200 call out

 

[ChrisR]

Read all about it on the Kamco website. You can hire a machine for £50 and do it yourself.

Corgigazza what filters do you use? I've seen the 22mm ones clog up quickly, and used 1 1/2" ones which collected almost nothing

 

[shaneo]

powerflushing yer great