Boiler with no (?) room stat, open-plan house

[yabartleby]

I've been asked to fit TRVs in a house that hasn't got a room stat. It used to have one but it was disconnected - I don't know whether or not by cowboys. The owner wants TRVs everywhere and doesn't see the need for a room stat. At the moment he controls the boiler with a timer that sits in the cupboard with the boiler, so even if it's got a thermostat built in (I don't know about that) it can't be doing much good, can it? So question 1 is, do I tell him he's got to get a room stat? Am I missing some way the current set-up could be okay?

Question 2 is where to put a room stat. The problem is that the house is a typical 3-bed semi but the downstairs has been been knocked though into a single space (apart from a very small hall) that contains kitchen, living and dining areas and a big glass conservatory. The (3) rads were obviously positioned before all the knocking-through happened and the whole space is unevenly heated. This is why the owner wants TRVs, so he can fiddle with the heat. Is the answer to put a wireless room stat out in the hall and TRVs in the big space? There is a huge rad in the hall, though.

 

[simond]

I'd recommend a Honeywell CM927 in the ground floor space and no TRVs anywhere in the open space - but fitted everywhere else.

Might end up cheaper too. He'll need the air stat with a conservatory, it'll be very cold this winter otherwise, ho ho.

 

[yabartleby]

Thanks simond. I thought that too, about locating the room stat, but the bloke wants the TRVs in the big open space so he can set different temps in different areas at different times of day, say turning up a rad to watch telly.

 

[gas4you]

Simons is one option but I would go for the stat in the hall and trv's everywhere else.

Do not put a room stat anywhere hear the kitchen area, or an area influenced by the heat from the kitchen.

Unfortunately neither Simon or I are at your site to advise 100%, so it is down to you and your experience to decide which option to go for.

If you can't make a decision then all I can suggest is to trv everything and where you put the wireless stat leave the trv on full.

 

[yabartleby]

where you put the wireless stat leave the trv on full

Every room apart from the big space is smallish (including the hall which has got a huge rad) so wouldn't the TRV on full near the stat mean that the big space wasn't getting enough heat?

 

[gas4you]

In that case yes. As I said it is down to you to assess the best position.

 

[yabartleby]

How about a room stat AND TRVs in the big room, but the rad nearest the stat doesn't get a TRV? I agree it's down to me to assess the best position but this great big space with hot spots, cold spots and a kitchen is hard for me to get my head around. I'd appreciate any tips on working out the best position.

 

[gas4you]

That is a possibility and with a wireless stat you could experiment with the positioning.

 

[D_Hailsham]

There is a huge rad in the hall, though.

Why is this rad huge? Is it expected to heat up the whole of the stairwell and landing? Or do the stairs go up in the living area?

Is the hall is separated from the rest of the downstairs by a door?

If so, put TRVs on all rads downstairs, except the hall, and on all rads upstairs.

Put the Wireless Programmer upstairs on the landing. Then adjust the flow valve on the hall rad so it is not pumping out so much heat that the wireless stat shuts the boiler down before the TRVs have had a chance to work.

If the customer wants to play around with the TRVs after you have gone, that's his problem - not yours

 

[Agile]

If the big space has several rads which are wrongly sized and positioned then I would agree that its perfectly correct to put TRVs on the inner/oversized rads.

The rad nearest the cold part like the window can be left with no TRV and the thermostat positioned within the room.

However, adopting that strategy does require the owner to accept that the big/inner rads MUST have their TRVs set to a lower setting so that its the rad with no TRV that finally influences the room stat.

Tony

 

[yabartleby]

Why is this rad huge? Is it expected to heat up the whole of the stairwell and landing?

I don't think much thought went into the original specs apart from the owner (who I know, distantly) insisting Bigger Is Better. And, Yes, the hall is separated from the rest of the downstairs by a door. Looks like I've got several sensible options now, thanks to everyone.