system or combi with a twist..

[ginoT]

Hi all’ya’ll !!

I’m caught between getting a system boiler or getting a combi boiler with a reserve tank. On paper I guess the system boiler is the only way. But the reason this is proving a tough decision is coz I do NOT think we want the whole house kitted out with central heating at the mo. Also it’s a relatively rare occurrence that there’ll be 2 people having showers + another person doing the washing up etc.. So question arises whether it’s really in my interest to go through the hassle of getting a system boiler + cylinder installed when maybe a combi boiler with integrated tank is enough for the time being (maybe at some unforeseen moment in the future I ‘might’ look into swapping over to a proper central heating set up.

These are the specs of the house:

Semi-detached, 3 floor
6 bedroom (only 2/3 people living there… but on the rare xmas-like occasion the place will be full)
1 bathroom
1 shower room
economy seven / electric heating throughout
an old heat-only boiler

additional concern is where’s the best place to put either boiler type? The higher up the better? Or ideally in between the shower & bathroom?

lastly if i really have to get a cylinder can I simply increase the size of the cold water pipes to avoid have to get a tank in the attic?

Muchos gracias!!

 

[Gasman1015]

Forget the system boiler then and use a combi, you could always add an unvented cylinder at a later date, which does not require attic tanks.
The closer the boiler is to the draw off points the better.
Assuming of course that your mains pressure is sufficient to cope with a combi and an unvented cylinder.

 

[ginoT]

yes true! tx. I think the mains pressure is ok I think but all the pipes are 15mm so if someone flushes the toilet etc.. then u get a sudden drop in the amount of water. The reserve in the combi will help to some extent but obviously not for the cold water.

I was thinking would it be a good idea to change the pipes to a large size? That way there'll be ample cold water available? The idea of cold water tanks in the attic, pumps, cylinders etc.. all straight away is just too much for me to take on. Any hints?!

 

[Gasman1015]

Check the flow rate from the kitchen tap(bucket and stop watch, how many litres per minute) and again with another mains water tap open.
You may need to get your incoming mains upgraded, increasing the pipe size
internally will not help unless its from the tanks.

 

[ginoT]

20l per minute - kitchen tap

15l per minute - kitchen tap + another mains on


what size should I get for the incoming mains? guess the bigger the better

 

[gas4you]

The reserve in the combi will help to some extent but obviously not for the cold water.

The reserve in the combi will not really help in this problem as it is still needing the mains pressure to 'push' the hot water out. A storage combi just mixes the hot with some cold to give a more plentiful supply.

 

[giblets]

I think the minumum recommended incoming main size is 25mm blue poly (MDPE) but I may be wrong.

 

[gas4you]

Your right giblets I think, as a mains cylinder needs 22mm to it all the way.

 

[ginoT]

so what are you guys saying? is my reserve combi , with larger incoming mains, + thermostatic showers idea a good temporary fix? like I said I really don't want to go through the cylinder idea unless is the only solution

 

[htgeng]

so what are you guys saying? is my reserve combi , with larger incoming mains, + thermostatic showers idea a good temporary fix? like I said I really don't want to go through the cylinder idea unless is the only solution

I wouldn't recommend a instantaneous heat solution for such a large property. Regardless of what you expect your current usage to be, you will surely underestimate it. Also it's worth considering the resale value of the property with a high quality stored system...

Spoil the ship for a ha'pworth of tar
If someone spoils the ship for a ha'pworth (halfpenny's worth) of tar, they spoil something completely by trying to make a small economy.

 

[ginoT]

yeah, I guess you're right. I have to say I would instantly go for the system solution if it wasn't for a regulation issue - apparently you cannot have the flue facing the neighbours (ie in the passageway between both houses). The alternative option is putting boiler + cylinder into a part of the house I don't want touching

anyway of getting around this?

 

[Gasman1015]

Yes, use a pluming kit.

 

[ginoT]

sorry, computer died on me last few days. What do you mean by "plumbing kit"? I thought plumbing kits were drainage pipes attached to sinks etc?

so again, what I'm looking for is a way to avert the neighbours getting cheesed off with the boiler's exhaust 1.5meters away from them

can you explain in a bit more detail in dumb a$$ friendly lingo

tx

 

[gas4you]

Put your specs on! Pluming kit, not PLUMBING kit

This is a flue extension that directs the exhaust gases upwards and away from the neigbourds property/boundary. Available for a few boilers these days. Could use one on a Vaillant 937 storage combi

 

[ginoT]

oh ok! TX!