Potterton boilers anyone?

[haveapear]

Our new house has a potterton boiler at least I think that's what it's called. I have no idea how old it is, the sellers weren't very forthcoming, but it must be quite old. It is either on or off and though works well can sometimes get too hot. We go round turning off radiators.

Add to this we need to put a walk in shower in and I think we'd be better to replace the boiler with a combi - that's what we had before and the shower was brilliant.

Dh disagrees, and thinks we should have an electric shower, and just replace the boiler when we need to. In the meantime fit a thermostat to it, but I've just read on another thread that electric showers give a weedy supply of water :(

Any views on what we should do?

[PigletJohn]

You must certainly fit a room thermostat and stop fiddling with the radiators.

If you were baking a cake you would set the temperature and let the oven manage itself, right?

I would recommend a programmable stat that enables you to set different temperatures for different times of day and days of the week. Honeywell are popular such as the CM907.
Not a wireless one as they go wrong more often.

Your system probably has a feed and expansion tank in the loft and would probably benefit. from a chemical clean which. is an inexpensive DIY job.


How many bathrooms and taps in your house?

[haveapear]

Thanks piglet 2 baths but no shower. It's better to keep the boiler then ?

There were 9 sinks when we moved in but we've removed 3! So are left with kitchen sink, old butler sink in the basement, 2 small sinks in the loos, 2 bigger sinks in the bathrooms. So including bathroom taps that adds up to 8 sets of taps I think . It's a 4 bed house and 4 of us live here so I don't think there'd be too much of a problem with losing hot water- there wasn't in the last house.

[PigletJohn]

a combi is rather slow to fill a bath. If there are 4 people in the house is is likely that there will sometimes be two taps running at the same time, and the available water will be shared out between them if you have a combi, and will be much slower, so is not very suitable for your house. What colour is your hot water cylinder?

Run the kitchen cold tap, or the garden tap if better, into a bucket; time it to full; calculate how many litres per minute you get. Surprise yourself by comparing this with the flow from the hot bath tap. What colour is the incoming cold water main to your house, at the stop cock under the sink or in the garden?

You do not mention the model of your boiler.

[haveapear]

Ok I will - have to go out in a minute .boiler says kingfisher on it.

I don't really like baths - prefer showers as does Dh. Although an inconvenience I think if someone wants a bath they can just wait . ( kids)

Cylinder is yellow - thanks for all your help :)

Will answer other question later .

[PigletJohn]

it appears that the older Potterton Kingfisher is about 78% efficient. It depends which model you have.

A good modern condensing boiler would be about 90% efficient, so you could expect to cut about an eighth off your gas usage. That alone would not cover the cost of change, so there is no immediate benefit from scrapping the old one. A new one will probably be smaller and quieter, and more powerful, so able to heat the house and cylinder faster from cold, but will automatically modulate its power down for economy according to demand. If you upgrade the controls at the same time, you can get other benefits. Fitting TRVs is a fairly simple job if you like DIY plumbing, but expensive if you have to pay someone. Giving the system a clean and fitting a system filter will reduce the load of sludge and sediment which an old, iron, open-vented system is likely to have, and this will improve performance and prevent future blockages, though I can't quantify it.

There is no great benefit in changing your cylinder, though you can upgrade if it becomes faulty and needs to be replaced. The yellow insulation is not as good as the latest models, so you would get a slight extra saving if you put a red jacket around it and insulate all the hot pipes with Climaflex or similar.