Why I like straight-forward design in a heating system
I am over-seeing a team of plumbers replacing corroded and scaled-up parts of a 1960’s heating system and making a few upgrades at the same time. It reminds me that an old, straight-forward design of heating system has its merits.
This system has two header tanks; one for the boiler circuits and one for cold feed to the hot water tank, the toilet cisterns and washbasin cold taps. The hot water storage tank is in a traditional ‘linen cupboard’. The system does have a floor-standing boiler and gravity loop to the hot water and I am not so keen on that.
Immediately I can see benefits in this ‘old-style’ straight-forward design, especially for ‘young’ or ‘old’ households. You have a tank of cold and a tank of hot water in the house. This means you will be self-contained for hot and cold water for several hours even if there is a power cut, or if the water or gas are turned off for maintenance (you don’t get that reliability of service with a combi-boiler which needs all three utilities to work; electricity, water and gas must all be there for the boiler to produce hot water).
Being self-contained is good news in a home where the old, infirm or very young live. Cleanliness and comfort are maintained and so a healthy and happy environment.
The linen cupboard is also a great place for keeping towels sweet-smelling and beautifully dry (and warm when used directly from the cupboard). You would have to store things somewhere anyway so why get rid of it?
And what do you lose by having this system? Not much really. There are some ‘standing losses’ from the hot water tank, but this is tiny if you have a well insulated tank and for half the year or more this heat-leakage helps heat the house. Independent sources say around 10% or you heating bill is for hot water so a bit of leaky heat here does not cost much.
So, if you asked me about conventional heating system design, my preference would be for a condensing gas boiler, a pumped system with divert-er valves to hot water tank and/or central heating, a twin coil tank with the lower coil fed from solar panels and a good quality time-of-day and day-of week controller plus time-of-day and day-of week thermostats; all set correctly of course, and almost certainly with TRVs on the radiators but with a preference for under-floor heating is practical.
