Hot water cylinder 'robbing' radiators of heat?

Hi,
I've recently moved in to a new house with an indirect oil fired burner. As the rooms have always been at best 'Lukewarm', I increased the temperature on the Burner to 75C. It had originally been set to 60C and I thought this would solve the problem. However, there has not been any considerable increase in room temperatures. The sole benefit of Increasing the burner seemed to be heating the cylinder tank which now has scalding hot water!!
There is no thermostat on the cylinder. Is it safe to assume that the cylinder is 'robbing' the radiators of the heat that is required to heat the rooms. I Don't think there is anything wrong with the radiators themselves are they all warm consistently, but just not enough to throw out the heat required, even with the increase of temperature on the boiler.
Would a thermostat fitted to the hot water cylinder and set to 60C provide extra heat to the radiators?
Any advice greatly appreciated, Regards, John.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I should have mentioned that there is nothing within the system to differentiate between heating water and heating the radiatiors. It's an 'All or Nothing' situation!!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 9 Jan 2006 05:04:10 -0800, snipped-for-privacy@gmail.com wrote:

Is there a room thermostat anywhere? Does it work?
sponix
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Hi sPoNiX,
No room thermostats anywhere!! It's the simplest of heating systems. Just one button within the house to turn on the boiler and heat both water/radiators at the same time (Indirect system). I just need reassurance that fitting a thermostat to the cylinder and setting it to 60C will actually force extra heat into the radiators and help to warm the house a little better.
John.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 9 Jan 2006 05:59:01 -0800, snipped-for-privacy@gmail.com wrote:

Does it have radiator stats?
sponix
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
No radiator stats either. All radiators are open fully, they just need an extra burst of heat to help heat the house. I've turned back down the boiler setting to 60C, although this is reducing the heat from the radiators. When I had the boiler at 75C, the hot water was close to scalding and radiators were not giving off enough heat!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@gmail.com wrote:

It sounds like you have my problem, where the cylinder is essentially connected up like another radiator.
Is there a valve on either of the pipes going to/from the cylinder coil ? If so, you may be able to stop it down a bit to "balance" the cylinder better. If there is not, you would want to attach one.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

You haven't mentioned any pump(s), and what controls them?
--
Tony Williams.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Tony,
I'm a relative novice, but there is a pump connected to the boiler which I'm assuming drives the circulation of the water. This appears to be working OK. Like I said, the entire system appeasr to work OK, the radiators just need that extra boost which I feel is constantly being lost to the hot water cylinder. When the boiler is turned up high, it is impossible to touch the hot water cylinder due to its heat - It's easily the hottest radiator in the house!!
I just want to be sure that bypassing the cylinder via a thermostat and motorized valve would help the radiators heat a little better. It's not a job I would be attempting myself, but it would be nice to know that this is the right route to take.
John.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

It sounds like you have a fault somewhere that is causing the pump to circulate boiler water through the h/w cylinder only.

See if you can find a fault first, before trying to re-design the system.
Our system pumps to the radiators and the h/w is gravity-feed only. So my knowlege is limited and it would be prudent to bow out now.
Stand by for more questions from people with more knowlege.... probably questions about exactly what controls the pump, and how the pump output is shared between the radiators and the h/w cylinder. (Or something).
--
Tony Williams.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@gmail.com wrote:

As other people have said you really need to find out exactly what you've already got before you go messing with it. Spend some time and effort drawing yourself a diagram of which bits are where and find out how they all join up. Looking in places which aren't at first obvious like behind that pile of towels in the airing cupboard can reveal heating components you didn't know existed!
In particular I'd be on the lookout for a manual valve near the HW cylinder, possibly with it's handwheel removed. I'd expect there to be one to restrict the flow through the cylinder and balance the system. It should be turned on just enough to allow some flow through the heating coil of the cylinder but not so much that the water sees an easy path back to the pump and simply can't be bothered going through all those boring radiators.
In principle fitting a thermostat controlled motorised valve to the flow through the cylinder is a very good idea (essential in my book) as it allows you to heat the radiators to a higher temperature than that at which you wish to store your hot water. BUT you must restrict the flow through the heating coil of the cylinder as well or whenever the cylinder thermostat is calling for heat you'll be back where you are now.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
In an earlier contribution to this discussion,

What do you propose would be controlled by the thermostat? If you want the radiators to continue to get hot without heating the hot water any futher, you need to physically stop the water from circulating through the cylinder's indirect coil - for which you need a motorised valve.
You don't say whether both CH and HW are pumped? Either way, you need a decent control system with valves and stats - which gives you independent control over the CH and HW circuits. Exactly what you need depends on what you've got at the moment - a more detailed description of pumping arrangements etc. would be useful.
60C is a reasonable temperature for the HW, but the water going through the radiators needs to be at about 80C - which you should be able to achieve with a half-way decent control system.
--
Cheers,
Set Square
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

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.