Boiler “exercising”

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Tim+

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May 25, 2022, 5:58:23 AMMay 25
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Since the price of gas has gone up but I still have cheap rate electricity
for a few hours at night I’m no longer using my boiler to heat my hot
water. Consequently by boiler isn’t getting used at all at present.

I’m sure there’s no “right” answer but just curious as to whether other
folk “exercise” their boilers in these situations just to stop things like
pump and valves seizing up.

Now that I have my Wi-Fi switches it’s easy for me to program the boiler to
run for 1 minute a day or 5 minutes once a week say. Is there any reason
why a longer “exercise” like 5 minutes might be better than a short one?

Tim

--
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Theo

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May 25, 2022, 6:53:54 AMMay 25
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Tim+ <tim.d...@gmail.com> wrote:
> I’m sure there’s no “right” answer but just curious as to whether other
> folk “exercise” their boilers in these situations just to stop things like
> pump and valves seizing up.
>
> Now that I have my Wi-Fi switches it’s easy for me to program the boiler to
> run for 1 minute a day or 5 minutes once a week say. Is there any reason
> why a longer “exercise” like 5 minutes might be better than a short one?

My ASHP has a setting where it'll run the pump for default 30 seconds if it
hasn't run in the last 7 days. In the current setup the zone valves aren't
controlled by it (I have a todo to fix that), so they won't be opened.

I suppose you want to exercise the valves, the CH pump, the boiler internals
(pumps/valves/hex/etc). Depends on your setup whether a call for heat is first
opening a valve, which fires the pump, which calls for heat, which fires the
boiler. If you ran it for 1 minute that cycle might only fire the boiler
for seconds after waiting for zone valves to open etc.

Also I suppose there's the 'cold engine' effect, where combustion isn't
clean until things are up to temp. Not sure how much that applies to
boilers. But short cycling might cause some stresses.

I'd be tempted to go for 5 minutes a week if you can: maybe 5 mins heating
then 5 mins hot water, or something like that.

Theo

Nick Odell

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May 25, 2022, 6:59:53 AMMay 25
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On 25 May 2022 11:53:47 +0100 (BST), Theo
I've been doing fifteen minutes, once per month, to allow everything
to get up to operating temperature. Would I be better off running it
for a shorter period, more frequently?

Nick

Brian

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May 25, 2022, 4:52:45 PMMay 25
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Have you checked the numbers to see if using ‘ cheap’ electricity is
cheaper than using you boiler to heat a tank of hot water?

I’ve not done it recently but, certainly in the past, E7 was still far more
expensive than gas even in the days before condensing boilers.

Running the boiler to heat the hot water at the most convenient time for
you - remembering a well insulated tank will stay hot for hours- would kill
two birds with one stone.

Tim+

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May 26, 2022, 2:29:19 AMMay 26
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Brian <no...@lid.org> wrote:
> Tim+ <tim.d...@gmail.com> wrote:
>> Since the price of gas has gone up but I still have cheap rate electricity
>> for a few hours at night I’m no longer using my boiler to heat my hot
>> water. Consequently by boiler isn’t getting used at all at present.
>>
>> I’m sure there’s no “right” answer but just curious as to whether other
>> folk “exercise” their boilers in these situations just to stop things like
>> pump and valves seizing up.
>>
>> Now that I have my Wi-Fi switches it’s easy for me to program the boiler to
>> run for 1 minute a day or 5 minutes once a week say. Is there any reason
>> why a longer “exercise” like 5 minutes might be better than a short one?
>>
>> Tim
>>
>
> Have you checked the numbers to see if using ‘ cheap’ electricity is
> cheaper than using you boiler to heat a tank of hot water?

Yes.

Currently I’m paying 7.33p /kWhr on a flexible tariff for gas but on
5p/kWhr for electricity for four hours during the night. Add in boiler
inefficiency and electricity is a clear winner for me at the moment. Those
hours provide more than enough hot water throughout the day for us.

R D S

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May 26, 2022, 6:28:19 AMMay 26
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On 25/05/2022 10:58, Tim+ wrote:
> I’m sure there’s no “right” answer but just curious as to whether other
> folk “exercise” their boilers in these situations just to stop things like
> pump and valves seizing up.
>

A real first world problem, it bugs me in summer that the towel rad
isn't on so after a few uses your towel gets a bit damp and fusty, so I
give the heating a short blast every couple of days before or after I
jump in the shower, mindful too of what you mention.

I'm not sure how often we launder towels, I chuck mine in the wash when
it seems necessary but it's more frequent in winter.

Tim+

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May 26, 2022, 8:27:40 AMMay 26
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R D S <rsa...@yahoo.com> wrote:
> On 25/05/2022 10:58, Tim+ wrote:
>> I’m sure there’s no “right” answer but just curious as to whether other
>> folk “exercise” their boilers in these situations just to stop things like
>> pump and valves seizing up.
>>
>
> A real first world problem, it bugs me in summer that the towel rad
> isn't on so after a few uses your towel gets a bit damp and fusty, so I
> give the heating a short blast every couple of days before or after I
> jump in the shower, mindful too of what you mention.

Usually it’s possible to add an electric element to a towel radiator. We
have one timed to come on for 2 hours a day in the morning.

R D S

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May 26, 2022, 8:54:06 AMMay 26
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On 26/05/2022 13:27, Tim+ wrote:
>
> Usually it’s possible to add an electric element to a towel radiator. We
> have one timed to come on for 2 hours a day in the morning.
>
Yes, I gave this some thought, would you fit this as well as CH or
instead of?
If as well as where would you fit the element? At the bottom I presume
so CH return coming out of the top?

Tim+

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May 26, 2022, 9:38:20 AMMay 26
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R D S <rsa...@yahoo.com> wrote:
As well as. Both flow and return are in the bottom of my radiator and the
element is fitted in the flow.

See https://www.heatandthings.com/wp-content/uploads/2018/11/108004068.jpg

R D S

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May 26, 2022, 9:43:39 AMMay 26
to
On 26/05/2022 14:38, Tim+ wrote:
>
> As well as. Both flow and return are in the bottom of my radiator and the
> element is fitted in the flow.
>
> See https://www.heatandthings.com/wp-content/uploads/2018/11/108004068.jpg
>
Now then, I didn't know that was a thing!

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