New combi boiler-risks

diywhynot

teddysmum wrote: »

So a good installer would pressure check the system

No. He/she would advise customer of risk on quotation. Pressure testing would be a chargeable item and after system had been cleansed (as said above).

diywhynot

teddysmum wrote: »

How old is 'old' pipework ?

Depends on standard of original install and materials used. 10 year old copper, badly installed can be worse than 30 year old copper fit to a good standard.

A1P

teddysmum wrote: »

We have a 40 year-old semi with a 35 year-old central heating system and the boiler needs replacing. We are considering a combi , as there are only two of us and it would be nice to have the extra space in the airing cupboard. However, I am alarmed to have just read a thread where someone had burst pipes, following installation and people have commented that this could be due to the extra pressure in the system.


Is this common and does it tend to affect properties much older than ours ?


Amended question: Is it common with a property of the age ours is ?

The possible snags if you go for a boiler swap have been well covered in the posts so far.I know this is a money saving site but I think for once probably paying out more will be a saving long term and offer peace of mind.I would go for a new system so leaks,bursts,replacing valves etc + a power flush + filter for the system setting you back at least £450 are removed from the situation.If you have ancient radiators and the system has not been maintained-get rid.New 'convector' radiators are supposedly 20% more efficient and usually carry a 10 year guarantee,you will have TRV's ,wireless thermostat,filter fitted to keep the system clean.There are lots of mid -range boilers Ideal pro tec plus and Baxi Duo tec (Other makes will be suggested!!!) which can have 5/7 years guarantee.Depending where you are,you could have this with 10 rads and all above for around +/- £3000.No maintenance costs apart from annual service.A boiler swap,updating a clapped out system and power flushing + adding filter would not be much less.

I_have_spoken

For benefit of all, could you please identify which boiler brands are 'shoddily made in China'?

I have suspicions about mine from Guangdong Shenzhou Gas Appliance Co., Ltd.; "the fire never blow awaya"!

diywhynot

I_have_spoken wrote: »

I have suspicions about mine from Guangdong Shenzhou Gas Appliance Co., Ltd.; the fire never blow awaya!

So not Vaillant, WB, Glow-worm,Baxi, Potterton, Atag, Atmos, Intergas, Vokera, Ideal etc. Have you purchased a boiler from the linked company?

macman

CH install circa 1978 could be a single pipe system anyway?
OP, the main issue with a combi is whether your water pressure and flow is even adequate for a combi. Until you've established this by way of your RGI carrying out a site inspection, you can't make any decision.
What make/model of boiler is it and who told you that it needs replacing? What's actually wrong with it?

teddysmum

We only need 7 radiators, as I don't want one in the kitchen, where there is one at present and my husband has suggested a complete setup.


Pressure should be ok, as gas fitter, who did me a favour last year ( freed a trapped bird at no cost ) lives on our estate and said he was going to fit a combi in his own house.


The boiler is a Potterton, which had a part replaced by a Potterton specialist some years ago. He showed us how to start the bioler by tapping a pipe, but said it would eventually fail and need replacing. However, we have stopped using the boiler as there is obviously a problem with the pump (burning smell when used)


Where are WB, Baxi and Vaillant made ?

macman

The number of rads is irrelevant as to whether you fit a combi or conventional boiler. Any combi will drive your CH circuit. What determines the combi rating is the DHW requirement, and we don't know how many baths/showers you have.
The water pressure elsewhere on the estate is also irrelevant to what you may get at your property, and the flow rate is also critical. The only way to establish this is by a site survey.