I noticed yesterday that the pressure on our combi was low.
I discovered a leak where the lock shield valve attaches to the rad
stem. In fact the nut was surprisingly loose.
The question is how did this work loose?
The system has been stable for months and the rad (a towel rad) has
been installed for 18 months.
Could the recents very cold weather up here in Scotland be the cause?
It has dipped below -10 an number of times recently.
Should we keep the heating on during the coldest of nights?
In an earlier contribution to this discussion, skiffer
Presumably you've tightened up the union nut, and fixed the leak? I can't
think why cold weather would cause it to come loose - the usual cause is
insufficient tightening followed by vibration of some sort.
How cold does it get in the house during the night with the heating off?
Obviously you don't want the system to freeze up - but that's not all that
likely. As long as it doesn't freeze, and as long as you've got a nice warm
duvet, it probably doesn't matter that it gets cold - unless you regularly
have to get up multiple times during the night.
Have you got a frost stat? Most programmable room stats act as frost stats
when the system is off, and turn on the heating if the the temperature falls
below (usually) 5degC. Something like that might suit you. Or (again with a
programmable stat) you could simply set the overnight temperature to (say)
12 degC to keep the house off the chill.
Why not just set back the temperature, rather than turning it off?
Our is left on winter and summer, 24/7 - all we ever do is turn the
stat down over night and when the house is not occupied. At the moment
we are setting it back to 15 degrees. Even when it was -6 earlier in
the week, it never fired, because the interior never fell below 18.5
degrees over night.
I had thought of that, but discounted it on the grounds that whatever
times it were set to would not rally suite us. It is simpler and easier
just to set two of the stat range stop pins and move it between them as
needed. Thinking about it though, I wonder if they do stats with built
in occupancy detectors.
On Wed, 30 Dec 2009 23:49:28 GMT, Harry Bloomfield
That's the problem with the Salus programmable 'stat I have .It has
"set" periods that you can set it for which is fine if those periods
suit you but in my case it doesn't really so if anyone knows a 'stat
where you can decide the periods coupled with the reqd temp please let
me know .
I'm not 100% sure what you mean, but I think that my Honeywell CM67 does
what you are looking for. It provides 6 time settings per 24 hours - so you
can divide the day into 6 (equal or unequal) periods to suit your
requirements. I use mine to effectively provide 3 on/off periods by setting
the temperatures of the 'off' periods low enough to prevent the heating from
coming on. The on/off times can be anything you like - and are not 'fixed'
until you have defined them. Is that what you want?
But there's an even cleverer bit - which it calls 'party' mode. The general
idea is that you might want to keep the heating on later if you're having a
party, but you can use it for anything you like - including turning the
heating off while you're out shopping (say). You simply press the 'party'
button, then select the number of hours, and then select the desired
temperature. This over-rides the fixed programme and controls the CH to
whatever you've set for the 'party' period.
Yup....sounds very much like what I need..in fact after I posted I had
another look at the Salus instructions .I was under the impression
that the "periods" it divided the day in to were set in stone but they
are not ...they can be changed to suit just like your Honeywell so
looks like I have already got what I am looking for . It just isn't
as simple to set the same specs for every day as it could be ...you
need to plod through each day period by period changing things to suit
but I spose it would only need to be done the once..
The Salus doesn't go to parties but you can override the programme
that is set at any time you want but when it gets to the next
"changeover period" it reverts to whatever that next period is set to
so if ,for example,it is at a lower temperature you might suddenly
realise it is getting cold and need to go and override it again .
What you have on the Honeywell sounds a better idea .
thx for your help.
On Wed, 30 Dec 2009 23:49:28 GMT, Harry Bloomfield wrote:
Eh, you mean there are programmable stats out there that have fixed
times only allowing the temp to be varied? That's a bit daft.
We have a Danfoss TP75 (superceeded now) that allows 6 programmable
time points through the day (I think down to 1 minute resolution),
each time point having a programmable temperature associated with it.
Each day, on a 7 day cycle, can have completly different programs
regarding both times and temps.
On Thu, 31 Dec 2009 10:47:10 +0000 (GMT), "Dave Liquorice"
That's what I thought ( as I posted seperately) about my Salus but
that was just me not reading the instructions properly . It does have
a number of set periods as a default but the time of them and the
temp can be altered so you could,for example,have it set to the same
temp thorought a 24 hour period ,every day if you wanted ....it's just
a bit of a pain going through it day by day to change it .
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.