Best way to regulate home heating

ZV Yoda

Hi there,

Long-winded post, but I’m trying to figure out how best regulate our home heating. I don’t know much about how they work, so I’ll describe the problem.

We have a Potterton Promax HE (3 years old). Our plumber advised us that we should keep the boiler temp at about 50 degrees to ensure we have sufficiently hot water in the taps. If anything, I find the water too hot (we have young kids). Also, at 50 degrees, the house gets very warm. I generally keep the boiler temp at 45 degrees (sometimes even lower).

Most/all of the rads have TRVs (8 downstairs, 7 upstairs & 2 in the attic). The TRVs are something like these (the dial goes from 1-5)
Even with these, we find it difficult to regulate the temp in each room (some get very warm). Depending on the room, some TRVs need to be set close to zero while others are at 5. There doesn’t appear to be any consistency relative to where the TRV is set (e.g. I’d like to be able to set each room to 19 degrees) but it seems to be trial an error with the TRVs. It doesn’t help that the kids of them change the settings (accidentally or otherwise).

The timer is something like this one:
.
I’m looking to replace it because some of the teeth have broken off and the dial is quite loose (it’s easy to accidentally knock off it & mess up the timing).

So, since I’m changing the timer anyway, should I use the opportunity to change how we regulate the heating? Would a digital timer with multiple zones improve things? Or how feasible/realistic would it be manage the temp in each room by installing wireless themostats in each room? Is all of this just overkill and should we just get better at using the TRVs?

Like I said, I’m not too well up on heating systems, but wanted to get some advice before replacing the timer.

Thanks

bbam

Have you had a BER assessment done. I'd advise have one done by a quality company and they can help.

You may be pouring heat into the house and it's being lost too quickly to regulate properly.

The best thing you can do for your heating is reduce the need to use it as much as possible..

ZV Yoda

bbam wrote: »

Have you had a BER assessment done. I'd advise have one done by a quality company and they can help.

You may be pouring heat into the house and it's being lost too quickly to regulate properly.

The best thing you can do for your heating is reduce the need to use it as much as possible..

We haven't had a BER assessment. I was thinking of getting one done. They seem expensive, but would probbaly save a fortune in the long run.

ZV Yoda

Just spoke with a BES assessor. They actually cost a lot less than I thought, but I don't think it's what I need. The assessor said ther BER would tell me whether we have a good/bad rating - but not neccessarily how to target/fix the issues.

Dardania

a few observations:

with the TRVs, you should just set them at a particular setting, and they should regulate to that temp. There shouldnt be any need for setting some to 0 and others to 5 - if you have to do that, I suspect theres problems with the TRV. Can you see any branding etc.? There are ways that TRVs can get stuck, so there are ways to repair them, or alternatively fit new heads to the existing valves that do work...
On my TRVs, halfway between 2 and 3 results in 19C.
The other option with TRVs, presuming that they're operating correctly, is that they may be overheating or underheating - are they horiztonally inclined so that the rad doesn't influence the TRV head?

With the domestic hot water, it seems that your boiler is most likely heating a hot water cylinder? If so, you NEED to store water above 60C (which means setting the flow temp from boiler at 65C or greater) to keep the water at 60C - otherwise you could have serious problems with legionnella forming. To deal with that at the aps, either use mixer taps, or thermostatic blending valves under the taps to bring the temp back down so thsat it won't scald people...
Do you have a separate control circuit (zone valve and cylinder thermostat) for the hot water cylinder?

Presuming that you get your TRVs working correctly, you should be comfortable even at higher flow temperature from the boiler (although it is less efficient)

With the issue of the programmer, I'd sugest getting a wireless programmable thermostat - that way you can program it for multiple timeslots, and also do frost protection & holiday mode. I'm very happy with this: http://www.heatingcontrolsonline.co.uk/honeywell-cmt927-cm927-wireless-programmable-room-thermostat-p-68.html , but suitability for your application is dependant on how you regulate your domestic hot water cylinder...

ZV Yoda

Dardania wrote: »

a few observations:

with the TRVs, you should just set them at a particular setting, and they should regulate to that temp. There shouldnt be any need for setting some to 0 and others to 5 - if you have to do that, I suspect theres problems with the TRV. Can you see any branding etc.? There are ways that TRVs can get stuck, so there are ways to repair them, or alternatively fit new heads to the existing valves that do work...
On my TRVs, halfway between 2 and 3 results in 19C.
The other option with TRVs, presuming that they're operating correctly, is that they may be overheating or underheating - are they horiztonally inclined so that the rad doesn't influence the TRV head?

With the domestic hot water, it seems that your boiler is most likely heating a hot water cylinder? If so, you NEED to store water above 60C (which means setting the flow temp from boiler at 65C or greater) to keep the water at 60C - otherwise you could have serious problems with legionnella forming. To deal with that at the aps, either use mixer taps, or thermostatic blending valves under the taps to bring the temp back down so thsat it won't scald people...
Do you have a separate control circuit (zone valve and cylinder thermostat) for the hot water cylinder?

Presuming that you get your TRVs working correctly, you should be comfortable even at higher flow temperature from the boiler (although it is less efficient)

With the issue of the programmer, I'd sugest getting a wireless programmable thermostat - that way you can program it for multiple timeslots, and also do frost protection & holiday mode. I'm very happy with this: http://www.heatingcontrolsonline.co.uk/honeywell-cmt927-cm927-wireless-programmable-room-thermostat-p-68.html , but suitability for your application is dependant on how you regulate your domestic hot water cylinder...

Thanks - some good points there. I'm going to check the orientation of the TRVs. I'll also reset them all to 1 & increase them over the next few days until each room hits a comfortable temp.

I'm not sure about the boiler heating the water cylinder (we also have an electric immersion which rarley gets used). Likewise, I dunno if we have separate zone for hot ater cylinder - how would I check?

Dardania

with the TRVs, if you find that doesn't do the trick, they're possibly just stuck. The way to fix them is to ake the head off, and push the valve pin up & down a few times to unseize...perfectly dry job so it is approachable. www.youtube.com/watch?v=nyCBMz6U6ZU

with the hot water cylinder controls, do you have a separate time clock timer for the hot water cylinder, or does it just get heated when you're heating the rooms also? have a look in your hot press, and see if you can see either a tap stat (basically another TRV with a sensing element on the side of the cylinder) or a zone valve with wires sticking out of it

ZV Yoda

Dardania wrote: »

with the TRVs, if you find that doesn't do the trick, they're possibly just stuck. The way to fix them is to ake the head off, and push the valve pin up & down a few times to unseize...perfectly dry job so it is approachable. www.youtube.com/watch?v=nyCBMz6U6ZU

with the hot water cylinder controls, do you have a separate time clock timer for the hot water cylinder, or does it just get heated when you're heating the rooms also? have a look in your hot press, and see if you can see either a tap stat (basically another TRV with a sensing element on the side of the cylinder) or a zone valve with wires sticking out of it

Thanks - I'll check the TRVs when I get home. No, we don't have a separate timer for hot water. Likewise, will check for TRV in the hot press when I get home too.

ZV Yoda

Looks like all of the TRVs are installed correctly, so that's good.

Can the Potterton Promax Plus 32 HE be cofigured as a dual system? Also, not sure if there is a TRV in the hotpress -when I looked I couldn't see anything the looked like a TRV.

Dardania

ZV Yoda wrote: »

Looks like all of the TRVs are installed correctly, so that's good.

Can the Potterton Promax Plus 32 HE be cofigured as a dual system? Also, not sure if there is a TRV in the hotpress -when I looked I couldn't see anything the looked like a TRV.

With a system boiler like that, technically there's no reason it couldn't be configured to have separate zones for space heating and for domestic hot water - the difficulty is with installing cabling between the boiler and the hot press.

The easier route is to put a tap stat (trv for hot water cylinder ) on the hot water cylinder, but wont reduce your gas costs, or allow you heat just the hit water cylinder easily...