new central heating

[AGrinWithoutACat]

Can anyone give me an idea of what to ask for - or look out for - when I get quotes to install a new central heating system please?

At present the house has no central heating, electric storage heaters only plus a gas fire in one room.

There is mains gas but no pipe work (other than to the one gas fire) and the hot water tank is a conventional one heated by electricity

It's a large detached house built in 1875 with thick sandstone walls, downstairs we have 2 reception rooms, kitchen and utility, second floor has 3 bedrooms, 2 bathrooms and a small box room, the attic has been converted with a further 2 bedrooms up there. There is a cold water tank in the converted attic area (storage cupboard between the two rooms) and the hot water tank in a cupboard off the utility room.

I think what I need is a system boiler (would love a combi but house too big) then radiators in each main room and the hall way, think 11 in total, and then I would prefer a heated towel rail in each of the bathrooms, would site a rad in the hallway outside them, and what ever pipe work is needed to connect it all together

Based on my description does this sound about right or is there something wonderful that I could do differently? Also would I be better to go with a large company like British Gas or SSE (in north Scotland) or look for local independents? And final Q - any recommend boiler brands?

Thank you for any advice

At that age the incoming water supply pipe is likely to be quite small, restricting flow, and to be made of iron or lead, and might start to leak, or already be leaking. If there is a water meter it will show if there is a leak. Ask your water company to test the drinking water for lead content, they might have a lead replacement scheme or subsidy.

I would start by assuming you need a new water pipe run out to the main under the pavement. It should be at least 25mm blue plastic but your house is quite large so I recommend 32mm. The extra cost of the larger pipe is slight, and the labour is the same, but the valves and stopcocks are dearer so insist on full-bore ones and verify that nobody fits small ones as they will restrict flow.

I would then go for an unvented hot water cylinder. Megaflo is a brand name, like Hoover.

Take a 22mm pipe from your 32mm incomer to the cylinder, and another 22mm pipe for your internal cold water. That way they will not be in contention for flow and e.g. the shower will not run cold or hot when somone turns a tap on. Again use full-bore Pegler service valves to avoid contricting the flow (also they will not start leaking, like 99p valves do).

When you say all this to your plumber he will know what you want to achieve. Look out for any corner-cutting.

As for boiler, look at Vaillant, Worcester-Bosch and Viessmann. Look at the manufacturer's website for their local approved installers. Plumbers and boilermen are opinionated and argumentative about which boiler is hest. I chose a Viessmann but make sure there is at least one approved installer near you. Study the websites for the terms of manufacturers' guarantees.

The gas pipe will presumably also need to be replaced. A gas engineer can calculate the size required from the distance between meter and boiler, and boiler power. Assume at least a 30kW boiler.

There is a tool for calculating heat loss and boiler power. I would go for radiators 50% bigger than calculated, because they will keep the house at a more even temperature and heat it up faster from cold. It does not matter if the radiators add up to more than the boiler, most of the time they will tick along at half power or less.

Ask for upstairs and downstairs heating zones on their own controls.

Obviously have TRVs.

I prefer wired to wireless controls as they go wrong less.

Thanks PigletJohn

Oops posted too soon but did say the important bit, will mention what you have said, I would agree with wired as signals on the house are patchy due to its construction/ layout but wouldn't have even thought about different controls for the different floors

May be a basic q but what are TRVs ?

thermostatic radiator valves

for example

Ah - thanks again - I'm sure by the end of this I will be well educated about heating terminology but at the moment am very much a beginner